Substituted dihydrobenzofuran glycosidase inhibitors

Abstract

Compounds of formula (I), wherein R′, R″, R, X, W, Q, n, and m have the meaning according to the claims, can be employed, inter alia, for the treatment of tauopathies and Alzheimer's disease. ##STR00001##

Claims

1. A compound of formula (I) ##STR00150## wherein R is straight chain or branched alkyl having 1 to 6 carbon atoms, wherein 1 to 5 hydrogen atoms may be replaced by Hal or OH; W is CH or N; X is N or CR′″; R′, R″ denote each independently H, Hal or straight chain or branched alkyl having 1 to 12 carbon atoms, wherein at least one of R′ and R″ is different from H; R′″ denotes H, Hal, NR.sup.3R.sup.4, CHR.sup.3R.sup.4, OR.sup.3, CN or a straight chain or branched alkyl having 1 to 12 carbon atoms, wherein 1 to 3 CH.sub.2-groups may be replaced by a group selected from O, NR.sup.3, S, SO, SO.sub.2, S(O)(NR.sup.3′), N(SO)R.sup.3′, CO, COO, OCO, CONR.sup.3, NR.sup.3CO, ##STR00151##  and wherein 1 to 5 hydrogen atoms may be replaced by Hal, NR.sup.3R.sup.4 or NO.sub.2 or by one of the following groups: ##STR00152##  or R′″ denotes one of the following groups: ##STR00153## R.sup.3, R.sup.4 denote each independently H or a straight chain or branched alkyl group having 1 to 12 carbon atoms; Q denotes one of the following groups: ##STR00154## ##STR00155## ##STR00156## Y is N or CR′″; Z.sup.1 is S, O, NR.sup.3; Z.sup.2, Z.sup.3 independently denote CR.sup.5 or N; Z.sup.4 is N, CH, CON, COCH; Z.sup.5 is NR.sup.8, CHR.sup.5, S(O)(NR.sup.3′), N(SO)R.sup.3′, ##STR00157## Z.sup.6 is CH.sub.2, CO, SO.sub.2, S(O)(NR.sup.3′), N(SO)R.sup.3′, ##STR00158## Z.sup.7 is C(R.sup.3′).sub.2, S, O, NR.sup.3′; s denotes 0 or 1; T is N, CH or CR.sup.7; R.sup.3′ denotes H or a straight chain or branched alkyl group having 1 to 12 carbon atoms, wherein 1 to 3 CH.sub.2-groups may be replaced by a group selected from SO.sub.2, CO, O and wherein 1 to 5 hydrogen atoms may be replaced by Hal; R.sup.5, R.sup.6, R.sup.7 independently denote H, Hal, NR.sup.3R.sup.4, NO.sub.2 or a straight chain or branched alkyl having 1 to 12 carbon atoms, wherein 1 to 3 CH.sub.2-groups may be replaced by a group selected from O, NR.sup.3, S, SO, SO.sub.2, S(O)(NR.sup.3′), N(SO)R.sup.3′, CO, COO, OCO, CONR.sup.3, NR.sup.3CO ##STR00159##  and wherein 1 to 5 hydrogen atoms may be replaced by Hal, NR.sup.3R.sup.4, NO.sub.2, OR.sup.3, Het, Ar, Cyc, or by one of the following groups: ##STR00160##  or R.sup.5, R.sup.6, R.sup.7 denote Ar, Het or Cyc or one of the following groups: ##STR00161## R.sup.8 denotes H or straight chain or branched alkyl having 1 to 12 carbon atoms, wherein 1 to 3 CH.sub.2-groups may be replaced by a group selected from SO, SO.sub.2, S(O)(NR.sup.3′), N(SO)R.sup.3′, CO, COO, OCO, CONR.sup.3, NR.sup.3CO, and ##STR00162## and further wherein 1 to 5 hydrogen atoms may be replaced by CN, OR.sup.3, SR.sup.3, Hal, NR.sup.3R.sup.4, NO.sub.2 or by one of the following groups: ##STR00163##  or R.sup.8 denote one of the following groups: ##STR00164## Hal denotes F, Cl, Br or I; Het denotes a saturated, unsaturated or aromatic ring, being monocyclic or bicyclic or fused-bicyclic and having 3- to 8-members and containing 1 to 4 heteroatoms selected from N, O and S, which may be substituted by 1 to 3 substituents selected from R.sup.5, Hal and OR.sup.3; Ar denotes a 6-membered carbocyclic aromatic ring or a fused or non-fused bicylic aromatic ring system, which is optionally substituted by 1 to 3 substituents independently selected from R.sup.5, OR.sup.3 and Hal; Cyc denotes a saturated or an unsaturated carbocyclic ring having from 3 to 8 carbon atoms which is optionally substituted by 1 to 3 substituents independently selected from R.sup.5 or Hal or OH; m and n denote independently from one another 0, 1, 2 or 3, t and q denote independently from one another 0, 1, 2 or 3, with t+q≥1; and pharmaceutically usable derivatives, solvates, salts, prodrugs, tautomers, enantiomers, racemates and stereoisomers thereof, including mixtures thereof in all ratios and compounds of formula I, wherein one or more H atoms are replaced by D (deuterium).

2. A compound chosen from the group consisting of formula Ia and Ib: ##STR00165## wherein R, R′, R″, X, W, Q, n and m have the meaning given in claim 1.

3. A mixture comprising compounds Ia and Ib according to claim 2, having identical groups R, R′, R″, X, W, Q, n and m in equal or unequal amounts.

4. A compound of formula I according to claim 1, wherein R is methyl and/or W is N.

5. A compound of formula I according to claim 1, wherein the groups X denote both simultaneously CH.

6. A compound of formula I according to claim 1, wherein Q denotes one of the following groups: ##STR00166## ##STR00167## ##STR00168## wherein T, Y, Z.sup.5, Z.sup.6, R′″, R.sup.5, R.sup.6, R.sup.7 and R.sup.8 have the meaning given in claim 1.

7. A compound of formula I according to claim 1, wherein R.sup.5, R.sup.6, R.sup.7 are independently selected from H, SO.sub.2CH.sub.3, SO.sub.2CH.sub.2CH.sub.3, SO.sub.2CH.sub.2CH.sub.2OH, SO.sub.2CH.sub.2CH.sub.2OCH.sub.3, S(O)(NR.sup.3′)CH.sub.3, S(O)(NR.sup.3′)CH.sub.2CH.sub.3, S(O)(NR.sup.3′)CH.sub.2CH.sub.2OH, S(O)(NR.sup.3′)CH.sub.2CH.sub.2OCH.sub.3, N(SO)R.sup.3′CH.sub.3, N(SO)R.sup.3′CH.sub.2CH.sub.3, N(SO)R.sup.3′CH.sub.2CH.sub.2OH, N(SO)R.sup.3′CH.sub.2CH.sub.2OCH.sub.3, Hal, NR.sup.3R.sup.4, NO.sub.2, phenyl, 2-, 3- or 4-hydroxy or methoxyphenyl, alkyl, alkoxy (Oalkyl), hydroxyalkylen, alkoxyalkylen, COOH, COOalkyl, CONHalkyl, CONH.sub.2, CON(CH.sub.3).sub.2, NHCOalkyl, NHCH.sub.2CH.sub.3, NHCH.sub.2CH.sub.2CH.sub.3, NHCOCH.sub.2CH.sub.2OH, CO—N-morpholinyl, CON(CH.sub.3)CH.sub.2CH.sub.2N(CH.sub.3).sub.2, CO-1-piperidinyl, CO-4-hydroxy-1-piperidinyl, CO-1-piperazinyl, CO-4-methyl-1-piperazinyl, CH.sub.2—N— morpholinyl, CH.sub.2N(H)COCH.sub.3, CH.sub.2N(CH.sub.3)COCH.sub.3, CH.sub.2NH.sub.2, NH.sub.2, CH(OH)CH.sub.3, CH(OR.sup.3)CH.sub.3 and a group ##STR00169## wherein t+q is 2 or 3, Z.sup.7, R.sup.3, R.sup.4 and R.sup.3′ have the meaning given in claim 1.

8. A compound of formula Ic ##STR00170## wherein R, R′, W, Q, n and m have the meaning given in claim 1.

9. A compound of formula I according to claim 1, wherein m and n simultaneously denote 1.

10. A compound according to claim 1, selected from the following group: TABLE-US-00005 Configuration No Structure specification 1 Racemic 2 Racemic 3 Racemic 4 Racemic 5 Racemic 6 Racemic 7 Racemic 8 Racemic 9 Synthesized from (R)-propane-1,2- diol 10 Synthesized from (R)-propane-1,2- diol 11 Chiral SFC Method A: 1st eluting compound 12 Chiral SFC Method A: 2nd eluting compound 13 Chiral SFC Method A: 1st eluting compound 14 Synthesized from (S)-propane-1,2- diol 15 Synthesized from (S)-propane-1,2- diol 16 Chiral SFC Method B: 1st eluting compound 17 Chiral SFC Method B: 2nd eluting compound 18 Chiral SFC Method C: 1st eluting compound 19 Synthesized from (R)-propane-1,2- diol 20 Synthesized from (R)-propane-1,2- diol 21 Synthesized from (R)-propane-1,2- diol and/or and pharmaceutically usable derivatives, solvates, salts, tautomers, enantiomers, racemates and stereoisomers thereof, including mixtures thereof in all ratios.

11. A compound of formula (I) according to claim 1 for use as a medicament.

12. A compound of formula (I) according to claim 1 and pharmaceutically usable derivatives, solvates, salts, tautomers, enantiomers, racemates and stereoisomers thereof, including mixtures thereof in all ratios for use in a treatment of a condition selected from neurodegenerative diseases, diabetes, cancer, cardiovascular diseases and stroke.

13. A compound for use in a treatment of a condition according to claim 12, wherein the condition is selected from the group of one or more tauopathies and Alzheimer's disease, Dementia, Amyotrophic lateral sclerosis (ALS), Amyotrophic lateral sclerosis with cognitive impairment (ALSci), Argyrophilic grain disease, Behavioural variant frontomeporal dmenetia (BvFTD), Bluit disease, Chronic traumatic encephalopathy, Corticobasal degeneration (CBP), Dementia pugilistica, Diffuse neurofibrillary tangles with calcification, Down's syndrome, Familial British dementia, Familial Danish dementia, Frontotemporal dementia with parkinsonism linked to chromosome 17 (FTDP-17), Frontotemporal lobar degeneration (FTLD), Ganglioglioma, Gangliocytoma, Gerstmann-Straussler-Scheinker disease, Globular glia tauopathy, Guadeloupean parkinsonism, Hallevorden-Spatz disease (neurodegeneration with brain iron accumulation type 1), Lead encephalopathy, Lipofuscinosis, Meningioangiomatosis, Multiple system atrophy, Myotonic dystrophy, Niemann-Pick disease (type C), Pallido-ponto-nigral degeneration, Parkinsonism-dementia complex of Guam, Pick's disease (PiD), Parkinson's disease dementia, Postencephalitic parkinsonism (PEP), Primary progressive aphasia, Prion diseases (including Creutzfeldt-Jakob Disease (GJD), Progressive nonfluent aphasia, Variant Creutzfeldt-Jakob Disease (vCJD), Fatal Familial Insomnia, Kuru, Progressive supercortical gliosis, Progressive supranuclear palsy (PSP), Semantic dementia, Steele-Richardson-Olszewski syndrome, Subacute sclerosing panencephalitis, Tangle-only dementia, Tuberous sclerosis, Huntington's disease and Parkinson's disease, preferably one or more tauopathies and Alzheimer's disease.

14. A method for treating a tauopathy, wherein a compound defined in claim 1 is administered to a mammal in need of such treatment.

15. A method for inhibiting a glycosidase, wherein a system expressing the glycosidase is contacted with a compound as defined in claim 1 under in-vitro conditions such that the glycosidase is inhibited.

16. A pharmaceutical composition comprising as active ingredient a compound according to claim 1 together with pharmaceutically tolerable adjuvants and/or excipients, optionally in combination with one or more further active ingredients.

Description

EXPERIMENTAL PART

(1) The compounds according to Formula (I) can be prepared from readily available starting materials by several synthetic approaches, using both solution-phase and solid-phase chemistry protocols or mixed solution and solid phase protocols. Examples of synthetic pathways are described below in the examples. All reported yields are non optimized yields. Unless otherwise stated, compounds of Formula (I) and related formulae obtained as a racemic mixture can be separated to provide an enantiomerically enriched mixture or a pure enantiomer.

(2) The commercially available starting materials used in the following experimental description were purchased from Aldrich, Sigma, ACROS, ABCR, Combi-Blocks, Matrix, Apollo scientific, Alfa Aesar, etc. unless otherwise reported.

(3) The HPLC, MS and NMR data provided in the examples described below are obtained as followed:

(4) .sup.1H NMR analyses were carried out using BRUKER NMR, model AV-II and AV-III 400 MHz FT-NMR. Residual signal of deuterated solvent was used as internal reference. Chemical shifts (δ) are reported in ppm in relative to the residual solvent signal (δ=2.50 for .sup.1H NMR in DMSO-d.sub.6, and 7.26 in CDCl.sub.3). s (singlet), d (doublet), t (triplet), q (quadruplet), br (broad), quint (quintuplet).

(5) LCMS Analysis Condition:

(6) Instrument Name:

(7) Agilent Technologies 1290 infinity 11.

(8) Method A:

(9) Method: A-0.1% TFA in H.sub.2O, B-0.1% TFA in ACN; flow rate: 2.0 mL/min; column: XBridge C8 (50×4.6 mm, 3.5 μm), +ve mode

(10) Method B:

(11) Method: A-10 mM NH.sub.4HCO.sub.3 in H.sub.2O, B-ACN; flow rate: 1.0 mL/min; column: XBridge C8 (50×4.6 mm, 3.5 μm), +ve mode

(12) HPLC Analysis Condition:

(13) Instrument Name:

(14) Agilent 1200 Series instruments as followed using % with UV detection (maxplot).

(15) Method A:

(16) Method: A-0.1% TFA in H.sub.2O, B-0.1% TFA in ACN; flow rate: 2.0 mL/min; column: XBridge C8 (50×4.6 mm, 3.5 μm).

(17) Method B:

(18) Method: A-10 mM NH.sub.4HCO.sub.3 in H.sub.2O, B-ACN; flow rate: 1.0 mL/min; column: XBridge C8 (50×4.6 mm, 3.5 μm).

(19) Chiral SFC Analysis Condition:

(20) Instrument Name:

(21) THAR-SFC 80 and THAR-SFC 200 (analytical) and Pic SFC 10-150 Ratio between CO.sub.2 and co-solvent is ranging between 50:50 and 90:10

(22) Method A:

(23) Mobile Phase: 20 mM Ammonia in Methanol flow: 4 mL/min; COLUMN: Lux C3 (250×4.6) mm, 5 μm

(24) Method B:

(25) Mobile Phase: 0.5% Isopropyl Amine in Methanol, 3 mL/min column: Chiracel OD-H (250×4.6) mm, 5 μm

(26) Method C:

(27) Mobile Phase: 20 mmol ammonia in Methanol, 3 mL/min column: Chiracel OJ-H (250×4.6) mm, 5 μm

(28) Chiral Preparative SFC Analysis Condition:

(29) Instrument Name:

(30) THAR-SFC 80, THAR-SFC 200 and Pic SFC 10-150

(31) Ratio between CO.sub.2 and co-solvent is ranging between 50:50 and 90:10

(32) Method A:

(33) Co-solvent: 20 mM Ammonia in Methanol flow: 5 mL/min; COLUMN: Lux C3 (250×30) mm, 5 μm

(34) Method B:

(35) Co-solvent: 0.5% Isopropyl Amine in Methanol, 5 mL/min column: Chiracel OD-H (250×30) mm, 5 μm

(36) Method C:

(37) Co-solvent: 20 mmol ammonia in Methanol, 5 mL/min column: Chiracel OJ-H (250×30) mm, 5 μm

(38) The microwave chemistry was performed on a single mode microwave reactor Initiator™ Sixty from Biotage.

(39) General flash chromatography conditions used for the purification of intermediates or compounds of Formula I: silica gel 230-400 mesh; gradients used as elutent: 10 to 80% EtOAc in petroleum ether or 1 to 15% MeOH in DCM

Intermediate 1: 6-(1-chloroethyl)-2-methyl-2,3-dihydrobenzofuran

(40) ##STR00061##

Step 1: 1-(3-(allyloxy)phenyl)ethan-1-one

(41) ##STR00062##

(42) To a stirred solution of 1-(3-hydroxyphenyl)ethan-1-one (25 g, 18.36 mol) in dry acetone (60 mL), potassium carbonate (81.2 g, 58.75 mol) was added at RT and the reaction mixture was stirred RT for 10 min. Allyl bromide (24 ml, 27.54 mol) was then added and the resulting mixture was refluxed for 6 h. Completion of the reaction was monitored by TLC, the reaction mixture was then filtered. The resulting filtrate was concentrated under vacuum to afford the title compound. Yield: 93% (30 g, brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.56 (d, J=8.0 Hz, 1H), 7.52 (t, J=2.0 Hz, 1H) 7.39 (t, J=7.6 Hz, 1H), 7.15 (dd, J=8.2, 2.8 Hz, 1H), 6.12-6.11 (m, 1H), 5.46 (dd, J=14.2, 1.2 Hz, 1H), 5.33 (dd, J=10.6, 1.2 Hz, 1H), 4.63-4.61 (m, 2H), 2.62 (s, 3H).

Step 2: Mixture of 1-(4-allyl-3-hydroxyphenyl) ethan-1-one and 1-(2-allyl-3-hydroxyphenyl) ethan-1-one

(43) ##STR00063##

(44) A solution of 1-(3-(allyloxy)phenyl)ethan-1-one (5.0 g, 36.7 mmol) in polyethylene glycol (10 mL) was stirred at 250° C. for 2 h under microwave irradiation. After completion of the reaction (monitored by TLC), water (10 mL) was added to the resulting mixture and the aqueous layer was extracted with EtOAc (2×50 mL). The combined organic layer was dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 30-50% EtOAc in hexane) to afford the title compound. Based on the LCMS analysis, the ratio between the two regio-isomers was 1.5:1. The mixture of regioisomer was forwarded to the next step as such. Yield: 57% (17 g, pale brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.50-7.49 (m, 1H), 7.24-7.20 (m, 2H), 7.01-6.99 (m, 1H), 6.08-6.02 (m, 1H), 5.19-5.08 (m, 1H), 4.15 (s, H), 3.49 (d, J=6.4 Hz, 2H), 2.08 (s, 3H). LCMS: (Method B) 175.2 (M−H), Rt 1: 4.9 min, 53.8%; Rt 2: 2.5 min, 34.3% (Max).

Step 3: 1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethan-1-one (Isomer A) and 1-(2-methyl-2,3-dihydrobenzofuran-4-yl)ethan-1-one (Isomer B)

(45) ##STR00064##

(46) To a stirred solution of 1-(4-allyl-3-hydroxyphenyl) ethan-1-one and 1-(2-allyl-3-hydroxyphenyl) ethan-1-one (17 g, 96.4 mmol) in dry DCM (60 mL), zirconium chloride (44 g, 0.19 mol) was added at RT and the reaction mixture was stirred at RT for 12 h. The reaction mixture was then filtered and the filtrate was concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, run time: 1.5 h (long run), eluent: 4% EtOAc in hexane) to give title compound to afford isomer A and isomer B.

(47) Analysis of isomer A: Yield: 6.0% (1.5 g, brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.49 (t, J=9.2 Hz, 1H), 7.33 (d, J=1.2 Hz, 1H), 7.24 (d, J=7.6 Hz, 1H), 5.03-5.01 (m, 1H), 3.41-3.35 (m, 1H), 2.90-2.84 (m, 1H), 2.57 (t, J=1.2 Hz, 3H), 1.50 (d, J=6.4 Hz, 3H). HPLC: (Method A) Rt. 3.5 min, 99.4% (Max).

(48) Analysis of isomer B: .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 7.37 (d, J=7.6 Hz, 1H), 7.24-7.18 (m, 1H), 6.95 (d, J=7.6 Hz, 1H), 5.00-4.94 (m, 1H), 3.72-3.65 (m, 1H), 3.18-3.11 (m, 1H), 2.60 (s, 3H), 1.49-1.47 (m, 3H). LCMS: (Method A) 177.3 (M+H), Rt. 3.7 min, 74.5% (Max).

Step 4: 1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethan-1-ol

(49) ##STR00065##

(50) To a stirred solution of 1-(2,3-dihydrobenzofuran-6-yl)ethan-1-one (0.32 g, 1.82 mmol) in methanol (7.4 mL, 20V) at 0° C., NaBH.sub.4 (0.14 mL, 3.60 mmol) was added and the reaction mixture was stirred at RT for 60 min. After completion (monitored by TLC), the reaction mixture was quenched with ice-cold water (5 mL) and the aqueous layer was extracted with DCM (2×10 mL). The combined organic layer was washed with brine (5 mL), dried over Na.sub.2SO.sub.4 and concentrated under vacuum to afford the title compound. Yield: 82.5% (crude, 0.25 g, brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.12 (d, J=7.4 Hz, 1H), 6.85 (d, J=7.4 Hz, 1H), 6.80 (s, 1H), 4.97-4.95 (m, 1H), 4.87-4.86 (m, 1H), 3.33-3.31 (m, 1H), 2.83-2.78 (m, 1H), 1.48-1.47 (m, 6H). LCMS: (Method A) 161.2 (M−H.sub.2O+H), Rt. 3.1 min, 99.7% (Max).

Step 5: 6-(1-chloroethyl)-2-methyl-2,3-dihydrobenzofuran

(51) ##STR00066##

(52) To a stirred solution of 1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethan-1-ol (0.25 mg, 1.90 mmol) in DCM (10 mL), SOCl.sub.2 (0.5 mL, 5.8 mmol) was added at 0° C., and the resulting mixture was stirred at RT for 2 hr. After completion of the reaction (monitored by TLC), the reaction mixture was concentrated under vacuum and the resulting crude was co-distilled with DCM (2×10 mL) to afford the title compound. The resulting solid was used for the next step without further purification. Yield: 80% (275 mg, pale brown gummy solid). .sup.1H NMR (300 MHz, CDCl.sub.3): δ 7.13 (d, J=7.5 Hz, 1H), 6.85 (m, 2H), 5.09-4.90 (m, 2H), 3.35-3.27 (m, 1H), 2.85-2.77 (m, 1H), 1.83 (d, J=8.00 Hz, 3H), 1.46 (d, J=6.3 Hz, 3H). LCMS: (Method A) 161.2 (M−HCl+H), Rt. 4.3 min 65.2% (Max).

Intermediate 2: N-(5-(piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide hydrochloride

(53) ##STR00067##

Step 1: tert-Butyl 4-(5-amino-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate

(54) ##STR00068##

(55) To a stirred solution of 2-amino 5-bromo-1,3,4-thiadiazole (10.0 g, 55.5 mmol) in dry DMF (100 mL), K.sub.2CO.sub.3 (15.3 g, 111.1 mmol) and 1-boc piperazine (12.4 g, 66.65 mmol) were added at 0° C. and the reaction mixture was stirred at 80° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was concentrated under vacuum. To the resulting mixture DCM (200 mL) was added, the organic layer was washed with water (100 mL), brine (100 mL) and dried over anhydrous Na.sub.2SO.sub.4. Then the organic layer was concentrated under vacuum and the resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 2-5% methanol in DCM) to afford the title compound. Yield: 76% (12 g, pale brown solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 6.51 (s, 2H), 3.39 (d, J=6.9 Hz, 4H), 3.19 (d, J=7.7 Hz, 4H), 1.39 (s, 9H). LCMS: (Method A) 286.1 (M+H), Rt. 2.7 min, 97.6% (Max).

Step 2: tert-Butyl 4-(5-acetamido-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate

(56) ##STR00069##

(57) To a stirred solution of tert-butyl 4-(5-amino-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate (12.0 g, 42.09 mmol) in pyridine (120 mL), acetic anhydride (5.1 g, 50.5 mmol) was added at 0° C. and the reaction mixture was stirred at 50° C. overnight. After completion of the reaction (monitored by TLC), the reaction mixture was concentrated under vacuum and the obtained material was triturated with diethyl ether (100 mL). The resulting crude material was filtered, dried under vacuum and forwarded to the next step as such without any further purification. Yield: 87% (12 g, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.07 (bs, 1H), 3.45-3.34 (m, 8H), 2.11 (s, 3H), 1.42 (s, 9H). LCMS: (Method A) 328.0 (M+H), Rt. 3.1 min, 86.3% (Max).

Step 3: N-(5-(Piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide hydrochloride

(58) ##STR00070##

(59) To a stirred solution of tert-butyl 4-(5-acetamido-1,3,4-thiadiazol-2-yl)piperazine-1-carboxylate (12.0 g) in dry 1,4-dioxane (100 mL) at 0° C., HCl solution in dioxane (100 mL, 4M) was added dropwise and the reaction mixture was stirred at RT for 3 h. After completion of the reaction (monitored by TLC), the reaction mixture was concentrated under vacuum and the obtained material was triturated with diethyl ether (50 mL). The resulting material was dried under vacuum and forwarded to the next step as such. Yield: 93% (9 g, white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.07 (bs, 1H), 3.67 (s, 4H), 3.21 (s, 4H), 2.13 (s, 3H). LCMS: (Method A) 228.0 (M+H), Rt. 0.7 min, 85.3% (Max).

Intermediate 3: 2-(piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5 (6H)-one hydrochloride

(60) ##STR00071##

Step 1: tert-butyl 4-carbamimidoylpiperazine-1-carboxylate

(61) ##STR00072##

(62) To the stirred solution of tert-butyl piperazine-1-carboxylate (20 g, 107.5 mmol) in DMF (200 mL), DIPEA (19.0 mL, 107.5 mmol) followed by 1H-pyrazole-1-carboxamide hydrochloride (15.76 g, 107.5 mmol) were added at RT and the reaction mixture was stirred at 60° C. for 6 h. After completion of the reaction (monitored by TLC), the reaction mixture was cooled at 0° C., MTBE (200 mL) was added and the reaction mixture was stirred for 1 h. The resulting solid material was washed with MTBE (2×50 mL), Et.sub.2O (50 mL) and dried under vacuum to afford the title compound. Yield: 83% (20 g, white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 7.71-7.69 (m, 3H), 3.44-3.34 (m, 8H), 1.42 (s, 9H).

Step 2: 3-((dimethylamino) methylene) piperidine-2,4-dione

(63) ##STR00073##

(64) To a stirred solution of 2,4-piperidinedione (10 g, 88.4 mmol) in ACN (100 mL), N, N-dimethyl formamide dimethylacetal (23.5 mL, 176.8 mmol) was added and the reaction mixture was stirred at RT overnight. After completion of the reaction (monitored by TLC), the resulting reaction mixture was evaporated under vacuum, the obtained crude material was triturated with diethyl ether (2×20 mL) and dried to afford the title compound. Yield: 92% (13.6 g, brown solid). .sup.1H NMR (300 MHz, DMSO-d.sub.6): δ 7.83 (s, 1H), 7.15 (s, 1H), 3.29 (s, 3H), 3.16 (t, J=6.3 Hz, 2H), 3.06 (s, 3H), 2.30 (t, J=6.3 Hz, 2H). LCMS: (Method A) 169.2 (M+H), Rt. 1.2 min, 90.4%.

Step 3: tert-butyl-4-(5-oxo-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-2-yl)piperazine-1-carboxylate

(65) ##STR00074##

(66) To a stirred solution of tert-butyl 4-carbamimidoylpiperazine-1-carboxylate (18.32 g, 80.2 mmol) and 3-((dimethylamino) methylene) piperidine-2,4-dione (13.5 g, 80.2 mmol) in EtOH (135 mL), K.sub.2CO.sub.3 (26.66 g, 193.0 mmol) was added and the reaction mixture was heated at 80° C. for 6 h. After completion of the reaction (monitored by TLC), the reaction mixture was cooled to RT and the obtained precipitate was collected by filtration. The resulting crude material was washed with EtOH (30 mL), water (3×30 mL), diethyl ether (2×20 mL) and dried under vacuum to afford the title compound. Yield: 85% (22.7 g, white solid). .sup.1H NMR (300 MHz, DMSO-d.sub.6): 8.63 (s, 1H), 7.74 (s, 1H), 3.85-3.81 (m, 4H), 3.41-3.39 (m, 6H), 2.82 (t, J=6.3 Hz, 2H), 1.43 (s, 9H). LCMS: (Method A) 334.2 (M+H), Rt. 3.4 min, 99.4% (Max).

Step 4: 2-(piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5 (6H)-one hydrochloride

(67) ##STR00075##

(68) To a stirred solution of tert-butyl-4-(5-oxo-5,6,7,8-tetrahydropyrido[4,3-d]pyrimidin-2-yl)piperazine-1-carboxylate (22 g, 66.0 mmol) in 1,4-dioxane (66 mL) at 0° C., HCl solution in dioxane (110 mL, 5V, 4M) was added dropwise and the reaction mixture was stirred at RT for 4 h. After completion of the reaction (monitored by TLC), the reaction mixture was filtered and the obtained solid was washed with EtOAc (3×30 mL). The resulting material was dried under vacuum to afford the title compound which was forwarded to the next step as such. Yield: 94% (19 g, white solid). LCMS: (Method A) 234.2 (M+H), Rt. 0.6 min, 94.8% (Max).

Intermediate 4: (2R)-6-(1-chloroethyl)-2-methyl-2,3-dihydrobenzofuran

(69) ##STR00076##

Step 1: (R)-1-(trityloxy)propan-2-ol

(70) ##STR00077##

(71) To a stirred solution of (R)-propane-1, 2-diol (15.0 g, 0.19 mol) in DCM (300 mL) at 0° C., TEA (44.37 mL, 0.31 mol) and tritylchloride (56 g, 0.20 mol) in DCM (100 mL) were added slowly under nitrogen atmosphere and the reaction mixture was stirred at RT overnight. After completion of the reaction (monitored by TLC), the reaction mixture was quenched with sat. NH.sub.4Cl (150 mL) and the aqueous layer was extracted with DCM (2×100 mL). The combined organic layer was washed with water (100 mL), brine (100 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum to afford the title compound. Yield: 84% (52.09 g, pale yellow gummy liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.49-7.42 (m, 6H), 7.35-7.29 (m, 6H), 7.28-7.25 (m, 3H), 4.03-3.98 (m, 1H), 3.16 (dd, J=9.2, 3.2 Hz, 1H), 3.02 (dd, J=9.2, 8.0 Hz, 1H), 2.39 (s, 1H), 1.09 (d, J=6.4 Hz, 3H).

Step 2: (R)-((2-(2,5-dibromophenoxy)propoxy)methanetriyl)tribenzene

(72) ##STR00078##

(73) To a stirred solution of 1, 4-dibromo-2-fluorobenzene (32 g, 0.13 mmol) and (R)-1-(trityloxy)propan-2-ol (44.24 g, 0.14 mmol) in THF (300 mL), KOtBu (56.8 g, 0.5 mmol) was added batchwise over 25 min at 5° C. and the reaction mixture was heated at 70° C. overnight. After completion of the reaction (monitored by TLC), the mixture was cooled to RT, diluted with water (150 mL) and the aqueous layer was extracted with EtOAc (2×150 mL). The combined organic layer was washed with water (100 mL), brine (100 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 6% EtOAc in hexane) to afford the title compound. Yield: 65% (45.3 g, off white solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.48-7.41 (m, 7H), 7.36-7.12 (m, 11H), 4.60-4.57 (m, 1H), 3.46 (dd, J=10.0, 6.4 Hz, 1H), 3.17 (dd, J=10.0, 6.2 Hz, 1H), 1.33 (d, J=6.4, Hz, 3H).

Step 3: (R)-2-(2, 5-dibromophenoxy) propan-1-ol

(74) ##STR00079##

(75) To a stirred solution of (R)-((2-(2,5-dibromophenoxy)propoxy)methanetriyl)tribenzene (25 g, 32.54 mmol) in dry DCM (250 mL), 10% TFA in DCM (50 mL) was added dropwise at 0° C. and the reaction mixture was stirred at RT for 1 h. After completion of the reaction (monitored by TLC), the mixture was cooled to 0° C., quenched with sat. NaHCO.sub.3 and the aqueous layer was extracted with DCM (2×150 mL). The combined organic layer was washed with brine (30 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 18% EtOAc in hexane) to afford the title compound. Yield: 32% (7.5 g, pale brown gummy oil). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.41 (d, J=8.4 Hz, 1H), 7.12 (s, 1H), 7.02 (d, J=8.8 Hz, 1H), 4.52-4.48 (m, 1H), 3.79 (m, 2H), 1.36 (d, J=6.4 Hz, 3H). HPLC: (Method A), Rt. 4.2 min, 99.7% (Max). Chiral SFC: (Method D), Rt 2.7 min, 96.6%.

Step 4: (R)-1, 4-dibromo-2-((1-bromopropan-2-yl)oxy)benzene

(76) ##STR00080##

(77) To a stirred solution of (R)-2-(2, 5-dibromophenoxy) propan-1-ol (7.0 g, 22.5 mmol) in DCM (70 mL), TPP (7.09 g, 27.09 mmol) and CBr.sub.4 (8.98 g, 27.09 mmol) were added under nitrogen atmosphere at 0° C. and the reaction mixture was stirred for 2 h at RT. After completion of the reaction (monitored by TLC), the mixture was evaporated under vacuum and the resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 10% EtOAc in hexane) to afford the title compound. Yield: 62% (5.1 g, pale brown gummy solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.43 (dd, J=8.4, 1.6 Hz, 1H), 7.09 (d, J=2.0 Hz, 1H), 7.09-7.03 (m, 1H), 4.58 (m, 1H), 3.61 (dd, J=10.6, 5.2 Hz, 1H), 3.50 (dd, J=8.4, 1.2 Hz, 1H), 1.53 (d, J=6.0 Hz, 3H).

Step 5: (R)-2-methyl-2, 3-dihydrobenzofuran-6-carbaldehyde

(78) ##STR00081##

(79) To a stirred solution of (R)-1, 4-dibromo-2-((1-bromopropan-2-yl)oxy)benzene (4.8 g, 0.013 mol) in dry THF (40 mL) under nitrogen atmosphere, n-butyl lithium (8.8 mL, 0.014 mol, 1.6 M in hexane) was added slowly over 10 min at −78° C. and stirred for 1 h. Second lot of n-butyl lithium (8.8 mL, 0.014 mol, 1.6 M in hexane) was added slowly over 10 min at −78° C. and stirring was continued for another 1 h. Then DMF (1.0 mL, 12.8 mmol) was added slowly, maintained for 45 min at −78° C. and completion of reaction was monitored by TLC. The reaction mixture was then warmed to 10° C., quenched with sat.NH.sub.4Cl solution (20 mL) and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with water (10 mL), brine solution (5 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 15-20% EtOAc in hexane) to afford the title compound. Yield: 78% (1.7 g, brown gummy oil). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 9.92 (s, 1H), 7.39 (dd, J=7.4, 1.2 Hz, 1H), 7.31 (d, J=7.8 Hz, 1H), 7.24 (s, 1H), 5.04-4.99 (m, 1H), 3.40 (dd, J=16.4, 8.8 Hz, 1H), 2.89 (dd, J=14.0, 2.8 Hz, 1H), 1.51 (d, J=6.4 Hz, 3H). LCMS: (Method A) 163.1 (M+H), Rt. 3.4 min, 64.6% (Max).

Step 6: 1-((R)-2-methyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-ol

(80) ##STR00082##

(81) To a stirred solution of (R)-2-methyl-2, 3-dihydrobenzofuran-6-carbaldehyde (1.6 g, 9.80 mmol) in dry THF (10 mL) under nitrogen atmosphere, methyl magnesium chloride solution (4.9 mL, 0.02 mol, 3 M in THF) was added slowly over 10 min at 0° C. and stirred for 2 h. Completion of the reaction was monitored by TLC, then the reaction mixture quenched by sat.NH.sub.4Cl solution (10 mL) and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with water (5 mL), brine solution (2 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 18% EtOAc in pet ether) to afford the title compound. Yield: 91% (1.0 g, pale yellow liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.14 (d, J=7.6 Hz, 1H), 6.86 (dd, J=7.4, 1.6 Hz, 1H), 6.81 (s, 1H), 4.98-4.92 (m, 1H), 4.86 (q, J=6.4 Hz, 1H), 3.31 (dd, J=15.2, 8.8 Hz 1H), 2.81 (dd, J=15.6, 7.6 Hz, 1H), 1.52 (s, 3H), 1.51 (d, J=6.8 Hz, 3H). LCMS: (Method A) 161.0 (M−H.sub.2O+H), Rt 2.2 min, 81.1% (Max).

Step 7: (2R)-6-(1-chloroethyl)-2-methyl-2, 3-dihydrobenzofuran

(82) ##STR00083##

(83) To a stirred solution of 1-((R)-2-methyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-ol (0.5 g, 2.80 mmol) in DCM (20 mL), SOCl.sub.2 (0.48 mL, 4.79 mmol) was added 0° C. and the reaction mixture was stirred at RT for 1 h. After completion of reaction (monitored by TLC), the mixture was concentrated under vacuum and the resulting crude material was co-distilled with dry DCM (2×500 mL) to afford the title compound. Yield: 98% (crude, 500 mg, brown gummy oil). LCMS: (Method A) 161.0 (M−HCl+H), Rt. 4.9 min, 35.9% (Max).

Intermediate 5: (2S)-6-(1-chloroethyl)-2-methyl-2,3-dihydrobenzofuran

(84) ##STR00084##

Step 1: (S)-1-(trityloxy)propan-2-ol

(85) ##STR00085##

(86) To a stirred solution of (S)-propane-1, 2-diol (10 g, 0.13 mol) in DCM (200 mL), TEA (30 ml 0.21 mol) and tritylchloride (36.63 g, 0.13 mol) in DCM (100 mL) were added slowly at 0° C. under nitrogen atmosphere and the reaction mixture was stirred at RT overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was quenched with sat. NH.sub.4Cl (150 mL) and the aqueous layer was extracted with DCM (2×100 mL). The combined organic layer was washed with water (100 mL), brine (50 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum to afford the title compound. Yield: 71% (30 g, pale yellow gummy oil). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.49-7.463 (m, 6H), 7.39-7.28 (m, 6H), 7.28-7.23 (m, 3H), 4.04-3.99 (m, 1H), 3.18 (dd, J=9.4, 3.6 Hz, 1H), 3.06-3.00 (m, 1H), 2.46 (d, J=3.2 Hz 1H), 1.14 (d, J=6.4 Hz, 3H). HPLC: (Method A), Rt. 5.5 min, 85.1% (Max).

Step 2: (S)-((2-(2, 5-dibromophenoxy)propoxy)methanetriyl)tribenzene

(87) ##STR00086##

(88) To a stirred solution of 1, 4-dibromo-2-fluorobenzene (22 g, 0.09 mol) and (S)-1-(trityloxy)propan-2-ol (27.65 g, 0.09 mol) in THF (300 mL), K.sup.tOBu (21.48 g, 0.191 mol) was added batchwise over 25 min at 5° C. and the reaction mixture was stirred at 70° C. overnight. After completion of the reaction (monitored by TLC), the mixture was cooled to RT, diluted with water (100 mL) and the aqueous layer was extracted with EtOAc (2×100 mL). The combined organic layer was washed with water (100 mL), brine (100 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was triturated with EtOAc to afford the title compound. Yield: 66% (25 g, off white solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.56 (d J=8.0 Hz 1H), 7.49 (s, 1H), 7.31-7.25 (m, 15H), 7.10 (dd, J=8.2, 1.2 Hz, 1H), 4.93 (s, 1H), 3.19 (dd, J=9.8, 6.8 Hz, 1H), 3.07 (d, J=7.6 Hz, 1H), 1.22 (d, J=6.4 Hz, 3H).

Step 3: (S)-2-(2, 5-dibromophenoxy) propan-1-ol

(89) ##STR00087##

(90) To a stirred solution of (S)-((2-(2, 5-dibromophenoxy)propoxy)methanetriyl)tribenzene (25 g, 45.28 mol) in dry DCM (250 mL), 10% TFA in DCM (100 mL) was added slowly at −20° C. and the reaction mixture was stirred for 2 h. Completion of the reaction was monitored by TLC, then the reaction mixture was quenched with sat. Na.sub.2CO.sub.3 at 0° C. and the aqueous layer was extracted with DCM (2×150 mL). The combined organic layer was washed with brine (40 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by recrystallization using methanol to afford the title compound. Yield: 57% (8.0 g, pale brown gummy oil). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.41 (d, J=8.3 Hz, 1H), 7.12 (d, J=2.0 Hz, 1H), 7.02 (dd, J=6.4, 2.1 Hz, 1H), 4.50 (t, J=4.4 Hz, 1H) 3.78 (t, J=4.1 Hz, 2H), 1.36 (d, J=6.2 Hz, 3H). HPLC: (Method A), Rt. 4.4 min, 97.1% (Max). Chiral SFC: (Method D) Rt. 3.3 min, 99.1% (Max).

Step 4: (S)-1, 4-dibromo-2-((1-bromopropan-2-yl)oxy)benzene

(91) ##STR00088##

(92) To a stirred solution of TPP (14.21 g, 0.06 mol) in DCM (50 ml), CBr.sub.4 (19.8 g, 0.06 mmol) was added slowly portion wise at 0° C. over 15 min, then (S)-2-(2, 5-dibromophenoxy) propan-1-ol (5.6 g, 0.02 mol) in DCM (20 mL) was added to it and the reaction mixture was stirred for 2 h at RT. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 10% EtOAc in hexane) to afford the title compound. Yield: 83% (5.1 g, pale brown gummy solid). .sup.1H NMR: (400 MHz, DMSO-d.sub.6): δ 7.53 (d, J=8.4 Hz, 1H), 7.43 (d, J=1.6 Hz, 1H), 7.11 (dd, J=8.4, 2.0 Hz, 1H), 4.90-4.88 (m, 1H), 3.77 (dd, J=11.0, 3.6 Hz, 1H), 3.67 (dd, J=11.2, 5.2, Hz, 1H), 1.34 (d, J=6.0 Hz, 3H).

Step 5: (S)-2-methyl-2, 3-dihydrobenzofuran-6-carbaldehyde

(93) ##STR00089##

(94) To a stirred solution of (S)-1, 4-dibromo-2-((1-bromopropan-2-yl)oxy)benzene (5.1 g, 0.01 mol) in dry THF (51 mL) under nitrogen atmosphere, n-Butyl lithium (9.42 mL, 0.02 mol, 1.6 M in hexane) was added slowly over 10 min at −78° C. After 1 h at the same temperature second lot of n-Butyl lithium (9.42 mL, 0.02 mol, 1.6 M in hexane) was added slowly over 10 min and stirring was continued for another 1 h. Then DMF (2.15 mL, 27.4 mmol) was added slowly maintaining at −78° C. for 45 min and completion of the reaction was monitored by TLC. The reaction mixture was then warmed to 10° C., quenched with sat. NH.sub.4Cl solution (20 mL) and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with water (10 mL), brine solution (5 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 8% EtOAc in hexane) to afford the title compound. Yield: 72% (1.6 g, brown gummy oil). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 9.93 (s, 1H), 7.39 (d, J=7.2 Hz, 1H), 7.33 (d, J=2.4 Hz, 1H), 7.29 (dd, J=7.8, 1.6, Hz, 1H), 5.05-5.01 (m, 1H), 3.40 (dd, J=16.4, 8.8 Hz, 1H), 2.90 (dd, J=16.6, 7.6 Hz, 1H), 1.51 (d, J=6.2 Hz, 3H). LCMS: (Method A) 163.1 (M+H), Rt. 2.5 min, 69.9% (Max).

Step 6: 1-((S)-2-methyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-ol

(95) ##STR00090##

(96) To a stirred solution of (S)-2-methyl-2, 3-dihydrobenzofuran-6-carbaldehyde (1.6 g, 9.80 mmol) in dry THF (16 mL) under nitrogen atmosphere, methyl magnesium chloride solution (4.9 mL, 0.02 mol, 3 M in THF) was added dropwise over 10 min at 0° C. and stirred for 2 h at the same temperature. After completion of the reaction (monitored by TLC), the mixture was quenched by sat. NH.sub.4Cl solution (10 mL) and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with water (5 mL), brine solution (2 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated at 45° C. under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 18% EtOAc in pet ether) to afford the title compound. Yield: 69% (1.22 g, pale yellow liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.14 (d, J=7.6 Hz, 1H), 6.86 (dd, J=7.6, 1.8, Hz, 1H), 6.81 (s, 1H), 4.98-4.93 (m, 1H), 4.84 (q, J=6.4 Hz, 1H), 3.32 (dd, J=15.2, 8.8 Hz, 1H), 2.82 (dd, J=15.6, 7.6 Hz, 1H), 1.56 (d, J=6.2 Hz, 3H), 1.47 (d, J=6.8 Hz, 3H). LCMS: (Method A) 161.1 (M−H.sub.2O+H), Rt 2.2 min, 97.3% (Max).

Step 7: (2S)-6-(1-chloroethyl)-2-methyl-2, 3-dihydrobenzofuran

(97) ##STR00091##

(98) To a stirred solution of 1-((S)-2-methyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-ol (1.2 g, 6.7 mmol) in DCM (12 mL), SOCl.sub.2 (1.5 mL, 20.1 mmol) was added at 0° C. and the reaction mixture was stirred at RT for 1 h. After completion of the reaction, the reaction mixture was concentrated under vacuum and the resulting crude material was co-distilled with dry DCM (3×5 mL) to afford the title compound. Yield: 98% (crude) (1.2 g, brown gummy oil).

Intermediate 6: 6-(1-chloroethyl)-2,2-dimethyl-2,3-dihydrobenzofuran

(99) ##STR00092##

Step 1: 1-bromo-3-((2-methylallyl) oxy)benzene

(100) ##STR00093##

(101) To a stirred solution of 3-bromophenol (Oakwood products, 10.0 g, 28.90 mmol) in dry acetone (60 mL), K.sub.2CO.sub.3 (8 g, 86.7 mmol) was added at RT and stirred for 10 min. Then 2-methyl-3-bromopropene (3.2 mL, 31.7 mmol) was added and the reaction mixture was refluxed for 6 h. Completion of the reaction was monitored by TLC, the reaction mixture was then filtered and the filtrate part was concentrated under vacuum. The resulting crude material was used in the next step without any further purification. Yield: 84% (11.0 g, brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): 7.28 (s, 1H), 7.17-7.01 (m, 2H), 6.89-6.86 (m, 1H), 5.10 (s, 1H), 5.02 (s, 1H), 4.44 (s, 2H), 1.85 (s, 3H).

Step 2: 5-bromo-2-(2-methylallyl) phenol and 3-bromo-2-(2-methylallyl) phenol

(102) ##STR00094##

(103) 1-Bromo-3-((2-methylallyl)oxy) benzene (11.0 g, 48.4 mmol) was added in polyethylene glycol (50 mL) at RT and the reaction mixture was stirred at 250° C. for 1 h under microwave irradiation. After completion of the reaction (monitored by TLC), water (100 mL) was added to the resulting mixture and the aqueous layer was extracted with EtOAc (2×100 mL). The combined organic layer was dried over Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 30-50% EtOAc in pet ether) to afford the title compound. The mixture of regioisomers (1.4:1) was used as such for the next step. Yield: 91% (10 g, brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.28 (s, 1H), 7.21-6.90 (m, 2H), 6.96-6.80 (m, 2H), 3.34 (s, 2H), 1.82 (s, 3H). LCMS: (Method B) 225.0 (M−H), Rt1: 6.4 min, 52.3%, Rt 2: 6.6 min, 36.3% (Max).

Step 3: 6-bromo-2, 2-dimethyl-2, 3-dihydrobenzofuran and 4-bromo-2, 2-dimethyl-2, 3-dihydrobenzofuran

(104) ##STR00095##

(105) A stirred solution of 5-bromo-2-(2-methylallyl)phenol and 3-bromo-2-(2-methylallyl)phenol regioisomer mixture (10 g, 44.0 mmol) in formic acid (30 mL) was refluxed for 10 h. Completion of the reaction was monitored by TLC and the reaction mixture was concentrated completely under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 15% EtOAc in pet ether) to afford the title compound. The mixture of regioisomer was forwarded to the next step as such. Yield: 80% (8 g, dark brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 6.98 (t, J=2.0 Hz, 1H), 6.96 (s, 1H), 6.66 (dd, J=6.8, 2.4 Hz, 1H), 3.03 (d, J=1.2 Hz, 1H), 2.96 (s, 1H), 1.51 (d, J=2.0 Hz, 3H), 1.48 (d, J=2.0 Hz, 3H).

Step 4: 1-(2,2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-one (Isomer A) and 1-(2,2-dimethyl-2,3-dihydrobenzofuran-4-yl)ethan-1-one (Isomer B)

(106) ##STR00096##

(107) To a degassed solution of 6-bromo-2, 2-dimethyl-2, 3-dihydrobenzofuran and 3-bromo-2, 2-dimethyl-2, 3-dihydrobenzofuran regioisomer mixture (7.6 g, 33.5 mmol) in dry toluene (100 mL), 1-ethoxy vinyl tributyl tin (14 ml, 40.15 mmol) and Pd(PPh.sub.3).sub.2Cl.sub.2 (940 mg, 1.2 mmol) were added and the resulting mixture was heated at 90° C. overnight. Completion of the reaction was monitored by TLC, then an aqueous solution of HCl (6N, 50 mL) was added and the mixture was stirred at 40° C. for 1 h. The reaction mixture was basified (pH-8) by using solid NaHCO.sub.3, filtered through celite and washed with EtOAc (100 mL). The organic layer was separated, washed with brine solution (100 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatgraphy (Biotage Isolera, eluent: 55% EtOAc in pet ether) to afford the isomer A and isomer B.

(108) Isomer A analysis: Yield: 30% (2.2 g, pale yellow liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.45 (dd, J=7.6, 1.2 Hz, 1H), 7.29 (d, J=1.2 Hz, 1H), 7.21 (d, J=7.6 Hz, 1H), 3.05 (s, 2H), 2.56 (s, 3H), 1.50 (s, 6H). LCMS: (Method A) 191.0 (M+H), Rt 4.0 min, 98.4% (Max).

(109) Isomer B analysis: Yield: 15% (500 mg, pale yellow liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.37 (d, J=8.0 Hz, 1H), 7.23 (t, J=8.0 Hz, 1H), 6.93 (d, J=8.0 Hz, 1H), 3.36 (s, 2H), 2.59 (s, 3H), 1.48 (s, 6H). LCMS: (Method A) 191.0 (M+H), Rt. 4.2 min, 99.2% (Max).

Step 5: 1-(2, 2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-ol

(110) ##STR00097##

(111) To a stirred solution of 1-(2, 2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-one (Isomer A, 2.1 g, 11.0 mmol) in methanol (11 mL) at 0° C., NaBH.sub.4 (838 mg, 22.0 mmol) was added and the reaction mixture was stirred at RT for 60 min. After completion of the reaction (monitored by TLC), the mixture was quenched with ice-cold water (5 mL) and extracted with DCM (2×30 mL). The combined organic layer was washed with brine (20 mL), dried over Na.sub.2SO.sub.4 and concentrated under vacuum to afford the title compound. Yield: 76% (crude) (1.6 g, brown liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.28 (s, 1H), 7.12 (d, J=7.6 Hz, 1H), 6.85 (d, J=1.2 Hz, 1H), 4.88-4.83 (m, 1H), 3.01 (s 2H), 1.50-1.48 (m, 9H). LCMS: (Method A) 175.0 (M+H), Rt. 3.5 min, 96.9% (Max).

Step 6: 6-(1-chloroethyl)-2, 2-dimethyl-2, 3-dihydrobenzofuran

(112) ##STR00098##

(113) To a stirred solution of 1-(2, 2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethan-1-ol (1.6 g, 8.32 mmol) in DCM (10 mL), SOCl.sub.2 (2.0 mL, 24.9 mmol) was added at 0° C. and the mixture was stirred at RT for 2 hr. After completion of the reaction (monitored by TLC), the mixture was then concentrated under vacuum to afford the title compound which was used in the next step without any further purification. Yield: 91% (1.75 g, pale brown gummy solid).

Intermediate 7: 1-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine dihydrochloride

(114) ##STR00099##

Step 1: tert-butyl 4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine-1-carboxylate

(115) ##STR00100##

(116) To a stirred solution of 1-Boc-piperazine (658 mg, 11.7 mmol) in DMF (3 mL), intermediate 1 (580 mg, 2.9 mmol) and TEA (1.60 mL, 11.7 mmol) were added and the reaction mixture was heated at 70° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. To the resulting mixture, water (5 mL) was added and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was dried over anhydrous Na.sub.2SO.sub.4, filtered and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 35% EtOAc in pet ether) to afford the title compound. Yield: 31% (250 mg, pale brown gum). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.06 (d, J=7.6 Hz, 1H), 6.75 (d, J=8.0 Hz, 1H), 6.70 (s, 1H), 4.96-4.92 (m, 1H), 3.47-3.27 (m, 5H), 2.86-2.82 (m, 1H), 2.45-2.42 (m, 5H), 1.47-1.42 (m, 12H), 1.36 (d, J=6.4 Hz, 3H). LCMS: (Method A) 347.3 (M+H), Rt. 3.7 min, 63.4% (Max).

Step 2: 1-(1-(2-methyl-2, 3-dihydrobenzofuran-6-yl)ethyl)piperazine dihydrochloride

(117) ##STR00101##

(118) To a stirred solution of tert-butyl 4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine-1-carboxylate (250 mg, 0.08 mmol) in dry 1, 4 dioxane (5 mL), HCl solution in dioxane (10 mL, 4M) was added at 0° C. dropwise and the reaction mixture was stirred at RT for 2 h. After completion of the reaction (monitored by TLC), the mixture was concentrated under vacuum to afford the tittle compound. Yield: 93% (600 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): 9.79-9.61 (m, 2H), 7.26 (d, J=7.6 Hz, 1H), 7.09-7.03 (m, 2H), 4.97-4.51 (m, 1H), 3.51 (q, J=6.6 Hz, 1H), 3.83-3.31 (m, 8H), 3.16-3.13 (m, 2H), 1.67 (d, J=6.6 Hz, 3H), 1.52 (d, J=6.4 Hz, 3H).

Intermediate 8: N-((2-chloropyrimidin-5-yl)(methyl)(oxo)-λ.SUP.6.-sulfanylidene)-2,2,2-trifluoroacetamide

(119) ##STR00102##

Step 1: 2-chloro-5-(methylthio)pyrimidine

(120) ##STR00103##

(121) To a stirred solution of 5-bromo-2-chloropyrimidine (5 g, 25.8 mmol) and 1, 2-dimethyldisulfane (2.92 g, 31.02 mmol) in THF (15 mL), n-BuLi (16.0 mL, 25.8 mmol, 1.6 M in hexane) was added at -78° C. and stirred for 1 h under the same temperature. After completion of the reaction (monitored by TLC), the reaction was then quenched with the addition of sat.NH.sub.4Cl (15 mL) and the aqueous layer was extracted with EtOAc (50 mL). The organic layer was washed with water (10 mL), brine (10 mL) and dried over anhydrous Na.sub.2SO.sub.4. The resulting crude material was purified by flash chromatography (silica gel: 60-120 mesh, eluent: 15% EtOAc in pet ether) to afford the title compound. Yield: 13% (0.6 g, white solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 8.50 (s, 2H), 2.56 (s, 3H). LCMS: (Method A) 161.1 (M+H), Rt. 2.1 min, 95.2% (Max). HPLC: (Method A) Rt. 2.4 min, 98.5% (Max).

Step 2: 2-chloro-5-(methylsulfinyl)pyrimidine

(122) ##STR00104##

(123) To a stirred solution of 2-chloro-5-(methylthio)pyrimidine (0.6 g, 2.49 mmol) in DCM (2 mL, 10 V), m-CPBA (0.644 g, 3.23 mmol) was added portion wise at 0° C. for 30 min. Completion of the reaction was monitored by TLC, the reaction mixture was then quenched with 10% NaHCO.sub.3 solution and extracted with DCM (2×100 mL). The combined organic layer was washed with brine (30 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 10-12% EtOAc in pet ether) to afford the title compound. Yield: 33% (330 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.88 (s, 2H), 2.92 (s, 3H). LCMS: (Method A) 177.1 (M+H), Rt. 0.8 min, 99.1% (Max). HPLC: (Method A) Rt. 1.9 min, 99.6% (Max).

Step 3: N-((2-chloropyrimidin-5-yl) (methyl)(oxo)-λ.SUP.6.-sulfanylidene)-2,2,2-trifluoroacetamide

(124) ##STR00105##

(125) To a stirred solution of 2-chloro-5-(methylsulfinyl)pyrimidine (0.9 g, 5.09 mmol) in DCM (18.0 mL, 20 V), trifluoroacetamide (1.15 g, 10.19 mmol), MgO (0.8 g, 20.38 mmol), Rh.sub.2(OAc).sub.4 (0.12 g, 0.25 mmol) and PhI(OAC).sub.2 (2.46 g, 7.64 mmol) were added and the reaction mixture was stirred at RT overnight. Completion of the reaction was monitored by TLC, the reaction mixture was then filtered through celite and the filtrate was concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 16-18% EtOAc in pet ether) to afford the title compound. Yield: 74% (1.1 g, white solid). LCMS: (Method A) 288.0 (M+H), Rt. 3.8 min, 71.1% (Max).

Intermediate 9: 1-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine dihydrochloride

(126) ##STR00106##

Step 1: tert-butyl 4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine-1-carboxylate

(127) ##STR00107##

(128) To a stirred solution of 1-Boc-piperazine (3.18 g, 17.08 mmol) in DMF (5.6 mL), intermediate 4 (2.8 g, 14.23 mmol) followed by TEA (8.00 mL, 56.94 mmol) were added slowly at RT and the reaction mixture was heated at 80° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. To the resulting mixture, water (20 mL) was added and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4, filtered and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 12% EtOAc in pet ether) to afford the title compound. Yield: 71% (3.45 g, pale brown gummy liquid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.08 (d, J=7.6 Hz, 1H), 6.75 (t, J=7.6 Hz, 2H), 4.96-4.92 (m, 1H), 3.40-3.25 (m, 6H), 2.80 (dd, J=15.4, 8.4 Hz, 1H), 2.41-2.37 (m, 4H), 1.49-1.44 (m, 12H), 1.35 (d, J=6.4 Hz, 3H). LCMS: (Method A) 347.2 (M+H), Rt 2.37 min, 81.0% (Max).

Step 2: 1-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine dihydrochloride

(129) ##STR00108##

(130) To a stirred solution of tert-butyl 4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine-1-carboxylate (3.4 g, 9.82 mmol) in dry 1, 4-dioxane (10 mL), HCl solution in dioxane (17 mL, 4M) was added dropwise at 0° C. and the reaction mixture was stirred at RT for 2 h. After completion of the reaction (monitored by TLC), the mixture was concentrated under vacuum and the resulting crude material was triturated with EtOAc to afford the tittle compound. Yield: 94% (2.9 g, pale brown solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 7.27 (d, J=7.6 Hz, 1H), 7.08 (q, J=4.4 Hz, 2H), 4.97-4.91 (m, 1H), 4.52 (s, 1H), 3.86-3.84 (m, 1H), 3.65-3.60 (m, 4H), 3.57 (m, 1H), 3.49-3.30 (m, 4H), 2.81-2.77 (m, 1H) 1.70 (d, J=6.4 Hz, 3H), 1.40 (d, J=6.4 Hz, 3H). LCMS: (Method A) 247.2 (M+H), Rt 1.7 min, 81.7% (Max).

Intermediate 10: 1-(1-(2,2-di methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazine dihydrochloride

(131) ##STR00109##

Step 1: tert-butyl 4-(1-(2, 2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethyl)piperazine-1-carboxylate

(132) ##STR00110##

(133) To a stirred solution of 1-boc-piperazine (960 mg, 22.19 mmol) in DMF (3 mL), intermediate 6 (900 mg, 4.21 mmol) was added and the reaction mixture was heated at 70° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. To the resulting mixture, water (5 mL) was added and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was dried over anhydrous Na.sub.2SO.sub.4, filtered and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 35% EtOAc in pet ether) to afford the title compound. Yield: 46% (700 mg, pale brown gummy solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.06 (d, J=7.6 Hz, 1H), 6.75 (q, J=8.0 Hz, 1H), 6.70 (s, 1H), 3.47-3.32 (m, 4H), 2.99 (s, 2H), 2.86-2.85 (m, 2H), 2.45-2.44 (m, 2H), 1.47-1.35 (m, 15H). 1.36 (d, J=6.4 Hz, 3H). LCMS: (Method A) 361.0 (M+H), Rt. 3.7 min, 63.4% (Max).

Step 2: 1-(1-(2,2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethyl)piperazine dihydrochloride

(134) ##STR00111##

(135) To a stirred solution of tert-butyl 4-(1-(2, 2-dimethyl-2, 3-dihydrobenzofuran-6-yl)ethyl)piperazine-1-carboxylate (700 mg, 1.94 mmol) in dry 1, 4 dioxane (5 mL), HCl solution in dioxane (4M, 10 mL) was added at 0° C. and stirred at RT for 2 h. Completion of the reaction was monitored by TLC, the reaction mixture was then concentrated under reduced pressure to afford the tittle compound. Yield: 93% (600 mg, off white solid). .sup.1H NMR (400 MHz, CDCl.sub.3): 12.3 (s, 1H), 9.64 (s, 2H), 7.26 (d, J=6.8 Hz, 1H), 7.05-7.04 (m, 2H), 4.50 (bs, 1H), 3.80-3.10 (m, 1H), 3.40-3.10 (m, 9H), 1.67 (s, 3H), 1.42-1.41 (m, 6H). LCMS: (Method A) 261.2 (M+H), Rt. 1.8 min, 82.2% (Max).

Example 1: N-(5-(4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(136) ##STR00112##

(137) To a stirred solution of intermediate 1 (0.200 g, 1.01 mmol) in DMF (2.5 mL), TEA (0.5 mL, 4.1 mmol) and intermediate 2 (0.254 g, 1.1 mmol) were added at RT and the reaction mixture was heated at 70° C. overnight. Completion of reaction was monitored by TLC, then the reaction mixture was concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 2-4% methanol in DCM) to afford the title compound. Yield: 10% (38.8 mg, pale brown solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.12 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.2 Hz, 1H), 6.68 (s, 1H), 4.89 (d, J=5.6 Hz, 1H), 3.34-3.31 (m, 4H), 3.24 (s, 1H), 2.78-2.76 (m, 2H), 2.51-2.43 (m, 4H), 2.10 (s, 3H), 1.39 (d, J=4.0 Hz, 3H), 1.28 (d, J=6.0 Hz, 3H). LCMS: (Method A) 388.3 (M+H), Rt. 2.6 min, 97.9% (Max). HPLC: (Method A) Rt. 2.6 min, 95.9% (Max).

Example 2: 2-(4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one

(138) ##STR00113##

(139) To a stirred solution of 1-(2-methyl-2,3-dihydrobenzofuran-5-yl)ethan-1-ol (200 mg, 1.0 mmol, synthesis described in intermediate 1, steps 1 to 4) in DCM (10 mL), thionyl chloride (1 ml) was added dropwise at 0° C. and the reaction mixture was stirred at RT for 1 h. After completion of the reaction (monitored by TLC), the reaction mixture was evaporated under vacuum and co-distilled with DCM (2×10 mL). The resulting mixture was dissolved in DCM (10 ml) and was added to a mixture of intermediate 3 (288 g, 1.28 mmol) and TEA (54 mg, 5.3 mmol) in DCM (10 mL) drop wise at RT and the reaction mixture was stirred at RT overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 75-80% EtOAc in pet ether) to afford the title compound. Yield: 25% (20 mg, pale brown solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.58 (s, 1H), 7.69 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.2 Hz, 1H), 6.68 (s, 1H), 4.89-4.87 (m, 1H), 3.80-3.79 (m, 4H), 3.38-3.24 (m, 5H), 2.80-2.67 (m, 4H), 2.46-2.43 (m, 1H), 2.37-2.33 (m, 1H), 1.39-1.37 (m, 3H), 1.28 (d, J=6.8 Hz, 3H). LCMS: (Method A) 394.5 (M+H), Rt. 2.6 min, 97.8% (Max). HPLC: (Method A) Rt. 2.6 min, 97.9% (Max).

Example 3: Imino(methyl)(2-(4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)-λ.SUP.6.-sulfanone

(140) ##STR00114##

Step 1: Imino(methyl)(2-(4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)-λ.SUP.6.-sulfanone

(141) ##STR00115##

(142) To a stirred solution of intermediate 7 (300 mg, 0.90 mmol) in DMF (2.5 mL), TEA (0.7 mL, 4.80 mmol) and intermediate 8 (300 mg, 1.2 mmol) were added at RT and stirred overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 50° C. under vacuum. To the resulting mixture, water (5 mL) was added and the aqueous layer was extracted with EtOAc (2×50 mL). The combined organic layer was dried over Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (silica gel: 230-400 mesh, eluent: 50% EtOAc in pet-ether) to obtain 2,2,2-trifluoro-N-(methyl(2-(4-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)(oxo)-λ.sup.6-sulfanylidene)acetamide. Yield: 30% (150 mg, off white solid).

(143) To this intermediate methanol (7 mL, 20 V) and K.sub.2CO.sub.3 (414 mg, 4.53 mmol) were added, and the resulting mixture was stirred at RT for 20 min. After 20 min, the reaction mixture was filtered through celite and concentrated under vacuum. To the resulting mixture, water (20 mL) was added and the aqueous layer was extracted with DCM (2×100 mL). The combined organic layer was dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 1-2% methanol in DCM) to afford the title compound. Yield: 20% (75 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.66 (s, 2H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.89-4.87 (m, 1H), 4.24 (s, 1H), 3.82-3.81 (m, 4H), 3.37-3.20 (m, 2H), 3.08 (s, 3H), 2.76-2.71 (m, 1H), 2.47-2.33 (m, 4H), 1.38 (q, J=2.4 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 402.0 (M+H), Rt 2.4 min, 99.0% (Max). HPLC: (Method A) Rt 2.4 min, 98.3% (Max).

Example 4: N-(5-(4-(1-(2,2-dimethyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(144) ##STR00116##

(145) To a stirred solution of intermediate 2 (356 mg, 1.56 mmol) and TEA (0.8 ml mg, 5.6 mmol) in dry DMF (3 mL), intermediate 6 (300 mg, 1.4 mmol) was added and the reaction mixture was heated at 75° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 45° C. under vacuum. To the resulting mixture, water (4 mL) was added and the aqueous layer was extracted with EtOAc (3×20 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 4-5% methanol in DCM) to afford the title compound. Yield: 7% (39.4 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.00 (s, 1H), 7.09 (d, J=7.6 Hz, 1H), 6.73 (d, J=7.6 Hz, 1H), 6.63 (s, 1H), 3.37-3.33 (m, 4H), 2.96 (s, 2H), 2.50-2.35 (m, 4H), 2.09 (s, 3H), 1.40 (s, 3H), 1.39 (s, 3H), 1.27 (d, J=6.4 Hz, 3H). LCMS: (Method A) 402.0 (M+H), Rt. 2.8 min, 94.7% (Max). HPLC: (Method A) Rt 2.7 min, 96.3% (Max).

Example 5: (2-(4-(1-(2,2-dimethyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)(imino)(methyl)-λ.SUP.6.-sulfanone

(146) ##STR00117##

(147) To a stirred solution of Intermediate 10 (400 mg, 1.20 mmol) in DMF (2.5 mL), TEA (0.7 mL, 4.80 mmol) and intermediate 8 (344 mg, 1.20 mmol, synthesis described in example 3, steps 1 to 5) were added at RT and the reaction mixture was stirred overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 50° C. under reduced pressure. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (2×50 mL). The combined organic layer was dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (silica gel: 230-400 mesh, eluent: 50% EtOAc in pet-ether) to obtain N-((2-(4-(1-(2,2-dimethyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)(methyl)(oxo)-λ.sup.6-sulfanylidene)-2,2,2-trifluoroacetamide. Yield: 23% (180 mg, off white solid). To this intermediate methanol (7 mL, 20 V) and K.sub.2CO.sub.3 (414 mg, 4.53 mmol) were added and stirred for 20 min. After 20 min, the reaction mixture was filtered through celite and concentrated under vacuum. To the resulting mixture, water (20 mL) was added and the aqueous layer was extracted with DCM (2×100 mL). The combined organic layer was dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 1-2% methanol in DCM) to afford the title compound. Yield: 18% (83.6 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.66 (s, 2H), 7.10 (d, J=7.6 Hz, 1H), 6.74 (d, J=7.6 Hz, 1H), 6.65 (s, 1H), 4.24 (s, 1H), 3.82 (s, 4H), 3.38 (t, J=6.8 Hz, 1H), 3.08 (s, 3H), 2.96 (s, 2H), 2.39-2.33 (m, 4H), 1.41-1.39 (m, 6H), 1.29 (d, J=6.8 Hz, 3H). LCMS: (Method A) 416.0 (M+H), Rt. 2.6 min, 99.6% (Max). HPLC: (Method A) Rt 2.5 min, 99.8% (Max).

Example 6: 2-(4-(1-(2,2-dimethyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one

(148) ##STR00118##

(149) To a stirred solution of intermediate 6 (300 mg, 1.4 mmol) in dry DMF (3 mL), TEA (0.8 mL, 5.6 mmol) and intermediate 3 (330 mg, 1.7 mmol) were added and the reaction mixture was heated at 75° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 45° C. under vacuum. To the resulting mixture, water (4 mL) was added and the aqueous layer was extracted with EtOAc (3×20 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 4-5% methanol in DCM) to afford the title compound. Yield: 22% (116.19 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.58 (s, 1H), 7.70 (s, 1H), 7.10 (d, J=7.6 Hz, 1H), 6.74 (d, J=7.2 Hz, 1H), 6.65 (s, 1H), 3.80-3.79 (s, 4H), 3.37-3.36 (m, 3H), 2.96 (s, 2H), 2.80-2.77 (t, J=6.8 Hz, 2H), 2.37-2.34 (m, 4H), 1.40 (d, J=2.8 Hz, 6H), 1.28 (d, J=6.8 Hz, 3H). LCMS: (Method A) 408.0 (M+H), Rt. 2.8 min, 98.5% (Max). HPLC: (Method A) Rt 2.7 min, 98.9% (Max).

Example 7: 1-(1-(2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)-4-(4-(methylsulfonyl)phenyl)piperazine

(150) ##STR00119##

Step 1: tert-butyl 4-(4-(methylsulfonyl)phenyl)piperazine-1-carboxylate

(151) ##STR00120##

(152) To a stirred solution of 1-fluoro-4-(methylsulfonyl)benzene (0.3 g, 1.7 mmol) in DMF (3 mL), N-Boc-piperazine (420 mg, 2.24 mmol) and TEA (1.0 ml, 6.86 mmol) were added at RT and the reaction mixture was heated at 80° C. for 12 h. Completion of the reaction was monitored by TLC, then the reaction mixture was concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 50% EtOAc in pet-ether) to afford the title compound. Yield: 43% (0.7 g, pale yellow colored solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 7.00 (d, J=8.8 Hz, 2H), 6.82 (d, J=9.2 Hz, 2H), 3.64 (t, J=4.8 Hz, 4H), 3.37 (t, J=4.8 Hz, 4H), 3.10 (s, 3H), 1.51 (s, 9H). LCMS: (Method A) 285.2 (M+H-tBu), Rt. 4.1 min, 51.9% (Max).

Step 2: 1-(4-(methylsulfonyl)phenyl)piperazine hydrochloride

(153) ##STR00121##

(154) To a stirred solution of tert-butyl 4-(4-(methylsulfonyl) phenyl)piperazine-1-carboxylate (0.6 g, 1.7 mmol) in dry 1, 4-dioxane (6 mL, 10 V) at 0° C., HCl solution in dioxane (2.2 mL, 4M) was added dropwise and the reaction mixture was stirred at RT for 10 min. Completion of the reaction was monitored by TLC, then the reaction mixture was concentrated under vacuum. The resulting crude material was triturated with EtOAc and evaporated under vacuum to afford the title compound. Yield: 46% (0.25 g, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 7.01 (d, J=16.0 Hz, 2H), 6.82 (d, J=8.0 Hz, 2H), 3.64 (t, J=4.8 Hz, 4H), 3.37 (t, J=4.8 Hz, 4H), 3.10 (s, 3H), 1.8 (s, 1H).

Step 3: 1-(1-(2-methyl-2, 3-dihydrobenzofuran-6-yl)ethyl)-4-4-(methylsulfonyl)phenyl)piperazine

(155) ##STR00122##

(156) To a stirred solution of 1-(4-(methylsulfonyl)phenyl)piperazine hydrochloride (0.22 g, 0.7 mmol) in DMF (2.5 mL), TEA (0.5 mL, 2.8 mmol) and intermediate 1 (0.17 g, 0.84 mmol) were added at RT and the reaction mixture was heated at 70° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 1-3% methanol in DCM) and the obtained material was further purified by prep HPLC (method B) to afford the title compound. Yield: 9% (20 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 7.66 (d, J=8.8 Hz, 2H), 7.12 (d, J=7.6 Hz, 1H), 7.04 (d, J=9.2 Hz, 2H), 6.75 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.89 (q, J=1.6 Hz, 1H), 3.36-3.24 (m, 6H), 3.08 (s, 3H), 2.75 (q, J=8.0 Hz, 1H), 2.43-2.33 (m, 4H), 1.38 (q, J=2.4 Hz, 3H), 1.29 (d, J=6.40 Hz, 3H). LCMS: (Method A) 401.0 (M+H), Rt. 2.9 min, 99.7% (Max). HPLC: (Method A) Rt. 2.9 min, 99.8% (Max).

Example 8: N-(5-(4-(1-(2-methyl-2,3-dihydrofuro[3,2-b]pyridin-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(157) ##STR00123##

Step 1: methyl 6-chloro-5-hydroxynicotinate

(158) ##STR00124##

(159) To a stirred solution of methyl-5-hydroxy nicotinate (10 g, 65.3 mmol, Combi blocks), 40% sodium hypochlorite solution (70 mL, 7V) was added at 0° C. for 2 h. Completion of the reaction was monitored by TLC, then 2N HCl solution (50 mL, 5V) was added slowly to the reaction mixture. The obtained white precipitate was collected by filtration and dried well under vacuum to afford the title compound. Yield: 42% (5.1 g, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.38 (s, 1H), 7.77 (s, 1H), 3.89 (s, 3H). LCMS: (Method A) 188.2 (M+H), Rt. 2.3 min, 63.1% (Max).

Step 2: methyl 2-methylfuro[3,2-b]pyridine-6-carboxylate

(160) ##STR00125##

(161) To a degassed solution of methyl 6-chloro-5-hydroxynicotinate (5.1 g, 27.4 mmol) in DMF, Pd(dppf)Cl.sub.2 (1.1 g, 1.37 mmol), CuI (0.52 g, 2.74 mmol), TEA (7.6 mL, 54.8 mmol) and followed by propargyl trimethylsilane (6.2 mL, 41.1 mmol) were added at RT and the reaction mixture was stirred at 60° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was filtered through celite and DMF was concentrated to dryness under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 15-25% EtOAc in pet ether) to afford the title compound. Yield: 46% (2.4 g, brown solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.99 (s, 1H), 8.37 (s, 1H), 6.92 (s, 1H), 3.90 (s, 3H), 2.51 (s, 3H). LCMS: (Method A) 192.0 (M+H), Rt. 2.1 min, 96.9% (Max).

Step 3: 2-methyl-2,3-dihydrofuro[3,2-b]pyridin-6-yl)methanol

(162) ##STR00126##

(163) To a stirred solution of methyl 2-methylfuro[3,2-b]pyridine-6-carboxylate (2.4 g, 12.5 mmol) in THF, LAH (15.1 mL, 15.07 mmol, 1M in THF) was added at −10° C. dropwise and the reaction mixture was stirred at RT for 1 h. Completion of the reaction was monitored by TLC, then the reaction mixture was quenched with saturated NH.sub.4Cl solution (15 mL) and the aqueous layer was extracted with EtOAc (2×40 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 2-4% methanol in DCM) to afford the title compound. Yield: 55% (1.1 g, brown gummy oil). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.55 (s, 1H), 8.33 (s, 1H), 5.34 (t, J=7.6 Hz, 1H), 5.11-5.00 (m, 1H), 4.61 (d, J=7.2 Hz, 2H), 3.54-3.47 (m, 1H), 3.02-2.96 (m, 1H), 1.46 (d, J=6.0 Hz, 3H). LCMS: (Method B) 166.0 (M+H), Rt. 2.5 min, 45.1% (Max).

Step 4: 2-methyl-2,3-dihydrofuro[3,2-b]pyridine-6-carbaldehyde

(164) ##STR00127##

(165) To a stirred solution of 2-methyl-2,3-dihydrofuro[3,2-b]pyridin-6-yl)methanol (1.1 g, 6.74 mmol) in DCM, dess-martin periodinane (4.3 g, 10.1 mmol) was added slowly at 0° C. and the reaction mixture was stirred at RT for 1 h. Completion of the reaction was monitored by TLC, then the reaction mixture was quenched with saturated NaHCO.sub.3 solution (10 mL) and the aqueous layer was extracted with DCM (2×30 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 30% EtOAc in pet ether) to afford the title compound. Yield: 15% (0.15 g, pale yellow solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 10.02 (s, 1H), 8.55 (s, 1H), 8.33 (s, 1H), 5.11-5.00 (m, 1H), 3.54-3.47 (m, 1H), 3.02-2.96 (m, 1H), 1.46 (d, J=6.0 Hz, 3H). LCMS: (Method B) 164.0 (M+H), Rt. 3.9 min, 42.9% (Max).

Step 5: 1-(2-methyl-2,3-dihydrofuro[3,2-b]pyridin-6-yl) ethan-1-ol

(166) ##STR00128##

(167) To the stirred solution of 2-methyl-2,3-dihydrofuro[3,2-b]pyridine-6-carbaldehyde (0.15 g, 0.86 mmol) in THF, methyl magnesium chloride (0.5 mL, 1.30 mmol, 3M solution in THF) was added dropwise at 0° C. and the reaction mixture was stirred at RT for 1 h. Completion of the reaction was monitored by TLC, then the reaction mixture was quenched with saturated NH.sub.4Cl solution (3 mL) and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with brine solution (5 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was forwarded as such to the next step without any further purification. Yield: 35% (0.05 g, yellow gummy oil). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.41 (s, 1H), 7.81 (s, 1H), 5.35 (d, J=4.4 Hz, 1H), 5.00-4.89 (m, 1H), 3.54-3.47 (m, 1H), 3.39-3.29 (m, 1H), 3.02-2.96 (m, 1H), 1.43 (d, J=8.0 Hz, 3H), 1.31 (d, J=6.4 Hz, 3H). LCMS: (Method A) 180.0 (M+H), Rt. 1.2 min, 54.3% (Max).

Step 6: 6-(1-chloroethyl)-2-methyl-2, 3-dihydrofuro[3,2-b]pyridine

(168) ##STR00129##

(169) To a stirred solution of 1-(2-methyl-2,3-dihydrofuro[3,2-b]pyridin-6-yl)ethan-1-ol (0.05 g, 0.27 mmol) in DCM, thionyl chloride (0.1 mL, 0.55 mmol) was added dropwise at 0° C. and the reaction mixture was stirred at RT for 1 h. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum to afford the title compound. Yield: 97% (0.05 g, brown gummy oil). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.61 (s, 1H), 8.10 (s, 1H), 5.40-5.34 (m, 1H), 5.09-4.97 (m, 1H), 3.54-3.47 (m, 1H), 3.02-2.96 (m, 1H), 1.44 (d, J=7.2 Hz, 3H), 1.23 (d, J=7.2 Hz, 3H). LCMS: (Method A) 198.2 (M+H), Rt. 2.4 min, 45.9% (Max).

Step 7: N-(5-(4-(1-(2-methyl-2, 3-dihydrofuro[3,2-b]pyridin-6-yl)ethyl)piperazin-1-yl)-1,3, 4-thiadiazol-2-yl)acetamide

(170) ##STR00130##

(171) To a stirred solution of intermediate 2 (0.17 g, 0.50 mmol) in DMF, TEA (0.18 mL, 1.26 mmol) followed by 6-(1-chloroethyl)-2-methyl-2,3-dihydrofuro[3,2-b]pyridine (0.05 g, 0.25 mmol) were added at RT and the reaction mixture was stirred at 70° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and evaporated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 0-5% methanol in DCM), then the obtained material was further purified by Prep-HPLC (Method B) to afford the title compound. Yield: 3% (0.002 g, off white solid). .sup.1H NMR (400 MHz, CDCl.sub.3): δ 7.98 (s, 1H), 7.19 (s, 1H), 5.07-5.05 (m, 1H), 3.70-3.65 (m, 4H), 3.49-3.43 (m, 1H), 3.30-3.18 (m, 1H), 2.99-2.93 (m, 1H), 2.77-2.74 (m, 4H), 2.34 (s, 3H), 1.55 (d, J=3.6 Hz, 3H), 1.27 (d, J=5.2 Hz, 3H). LCMS: (Method A) 389.0 (M+H), Rt. 1.8 min, 90.2% (Max). HPLC: (Method A) Rt. 1.7 min, 90.9% (Max).

Example 9: N-(5-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(172) ##STR00131##

(173) To a stirred solution intermediate 4 (0.5 g, 0.25 mmol) in DMF (2.5 mL), TEA (1.5 mL, 10.76 mmol) and intermediate 2 (0.64 g, 0.27 mmol) were added at RT and the reaction mixture was heated at 70° C. overnight. After completion of the reaction (monitored by TLC), the mixture was concentrated under vacuum and the resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 4-8% methanol in DCM) to afford the title compound. Yield: 11% (70 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.02 (s, 1H), 7.11 (d, J=7.2 Hz, 1H), 6.74 (d, J=7.2 Hz, 1H), 6.67 (s, 1H), 4.89 (t, J=6.0 Hz, 1H), 3.38-3.24 (m, 6H), 2.74 (q, J=7.6 Hz, 1H), 2.43-2.40 (m, 4H), 2.10 (s, 3H), 1.38 (t, J=2.0 Hz, 3H), 1.26 (t, J=6.8 Hz, 3H). LCMS: (Method A) 388.3 (M+H), Rt 2.5 min 99.9% (Max). HPLC: (Method A) Rt. 2.6 min, 99.8% (Max).

Example 10: 2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one

(174) ##STR00132##

(175) To a stirred solution of intermediate 3 (0.85 g, 0.27 mmol) in DMF (20 mL), TEA (1.5 mL, 10.76 mmol) and intermediate 4 (0.5 g, 0.25 mmol) were added at RT and the reaction mixture was heated at 80° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. To the resulting mixture, water (3 mL) was added and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 4-8% methanol in DCM) to afford the title compound. Yield: 18% (190 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.58 (d, J=2.8 Hz, 1H), 7.70 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.74 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.88 (q, J=8.0 Hz, 1H), 3.80 (m, 4H), 3.38-3.23 (m, 4H), 2.80-2.71 (m, 3H), 2.51-2.37 (m, 4H), 1.38 (q, J=2.8 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 394.2 (M+H), Rt. 2.5 min, 99.9% (Max). HPLC: (Method A), Rt 2.6 min, 99.8% (Max).

Examples 11 and 12: N-(5-(4-((R)-1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide and N-(5-(4-((S)-1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(176) ##STR00133##

(177) The enantiomers of example 9 was separated by SFC; mobile phase: 20 mM ammonia in methanol, column: LUX C3 (Method A), the first eluting peak was concentrated to afford the example 11 and the second eluting peak was concentrated to afford the example 12.

(178) Analysis of first eluting fraction (example 11): Yield: 40% (30 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.03 (s, 1H), 7.12 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.89 (q, J=6.4 Hz, 1H), 3.40-3.24 (m, 5H), 2.77-2.68 (m, 1H), 2.44-2.39 (m, 4H), 2.10 (s, 3H), 1.39 (d, J=6.0 Hz, 3H), 1.27 (t, J=6.4 Hz, 3H). LCMS: (Method A) 388.2 (M+H), Rt 2.5 min 99.2% (Max). HPLC: (Method A) Rt. 2.6 min, 99.8% (Max). Chiral SFC: (Method A) Rt. 3.8 min, 100% (Max).

(179) Analysis of second eluting fraction (example 12): Yield: 45% (32 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.03 (s, 1H), 7.12 (d, J=7.2 Hz, 1H), 6.75 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.90 (q, J=8.0 Hz, 1H), 3.40-3.24 (m, 5H), 2.77-2.68 (m, 1H), 2.42-2.34 (m, 4H), 2.09 (s, 3H), 1.38 (d, J=6.0 Hz, 3H), 1.27 (t, J=6.8 Hz, 3H). LCMS: (Method A) 388.3 (M+H), Rt. 2.5 min, 98.1% (Max). HPLC: (Method A) Rt. 2.6 min, 99.5% (Max). Chiral SFC: (Method A) Rt. 4.5 min, 99.3% (Max).

Example 13: 2-(4-((S)-1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one or 2-(4-((R)-1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one

(180) ##STR00134##

(181) The enantiomers of example 10 was separated by SFC; mobile phase: 20 mM ammonia in methanol, column: LUX C3 (Method A), the first eluting fraction was concentrated to afford example 13.

(182) Analysis of first eluting fraction (example 13): Yield: 40% (72 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.58 (s, 1H), 7.69 (s, 1H), 7.10 (d, J=7.6 Hz, 1H), 6.74 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.88 (q, J=8.4 Hz, 1H), 3.80-3.75 (m, 4H), 3.38-3.17 (m, 4H), 2.80-2.77 (m, 3H), 2.43-2.34 (m, 4H), 1.38 (d, J=6.4 Hz, 3H), 1.28 (t, J=6.8 Hz, 3H). LCMS: (Method A) 394.2 (M+H), Rt 2.5 min, 99.9% (Max). HPLC: (Method A), Rt 2.6 min, 99.9% (Max). Chiral SFC: (Method A) Rt. 4.0 min, 8.5% (Max).

Example 14: N-(5-(4-(1-((S)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(183) ##STR00135##

(184) To a stirred solution of intermediate 5 (0.6 g, 0.03 mol) in DMF (6 mL), TEA (2 mL) and intermediate 2 (0.76 g, 0.03 mol) were added at RT and the reaction mixtue was heated at 70° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was concentrated under vacuum. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with brine (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 4-8% methanol in DCM) to afford the title compound. Yield: 13% (150 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.02 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.2 Hz, 1H), 6.67 (s, 1H), 4.90 (t, J=8.0 Hz, 1H), 3.38-3.24 (m, 5H), 2.77-2.71 (m, 1H), 2.51-2.43 (m, 4H), 2.10 (s, 3H), 1.38 (q, J=2.4 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 388.1 (M+H), Rt 2.0 min, 97.9% (Max). HPLC: (Method A) Rt 2.5 min, 98.6% (Max). Chiral SFC: (Method B), Rt1. 3.8 min, 46.9%, Rt 2. 4.4 min, 53.1%.

Example 15: 2-(4-(1-((S)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one

(185) ##STR00136##

(186) To a stirred solution of intermediate 3 (1.02 g, 3.35 mmol) in DMF (6 mL), intermediate 5 (0.6 g, 3.0 mmol) and TEA (2.0 mL) were added at RT and the reaction mixture was heated at 80° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum. To the resulting mixture, water (10 mL) was added and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 4-8% methanol in DCM) to afford the title compound. Yield: 17% (200 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.58 (s, 1H), 7.70 (s, 1H), 7.11 (d, J=7.2 Hz, 1H), 6.74 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.88 (d, J=6.4 Hz, 1H), 3.80-3.78 (m, 4H), 3.37-3.24 (m, 4H), 2.80-2.68 (m, 3H), 2.51-2.34 (m, 4H), 1.38 (d, J=6.0 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 394.2 (M+H), Rt 2.0 min, 98.9% (Max). HPLC: (Method A), Rt 2.5 min, 98.7% (Max). Chiral SFC: (Method C), Rt 1. 2.2 min, 49.8% and Rt 2. 2.8 min, 49.4%.

Examples 16 and 17: N-(5-(4-((R)-1-((S)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide and N-(5-(4-((S)-1-((S)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2-yl)acetamide

(187) ##STR00137##

(188) The enantiomers of this racemic example 14 was separated by SFC; mobile phase: 0.5% isopropyl amine in methanol; column: Chiracel OD-H (Method B), the first eluting fraction was concentrated to afford example 16 and second eluting fraction was concentrated to afford example 17.

(189) Analysis of first eluting fraction (example 16): Yield: 35% (35 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.02 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.64 (d, J=7.6 Hz, 1H), 6.67 (s, 1H), 4.89 (q, J=7.2 Hz, 1H), 3.38-3.34 (m, 5H), 3.30-3.25 (m, 1H), 2.80-2.30 (m, 1H), 2.43-2.41 (m, 4H), 2.10 (s, 3H), 1.38 (d, J=6.4 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 388.1 (M+H), Rt 2.1 min, 99.1% (Max). HPLC: (Method A) Rt. 2.6 min, 96.3% (Max). Chiral SFC: (Method B) Rt. 3.9 min, 99.1% (Max).

(190) Analysis of second eluting fraction (example 17): Yield: 42% (42 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 12.02 (s, 1H), 7.12 (d, J=7.2 Hz, 1H), 6.75 (d, J=7.6 Hz, 1H), 6.67 (s, 1H), 4.89 (q, J=8.0 Hz, 1H), 3.36-3.33 (m, 6H), 2.80-2.75 (m, 1H), 2.51-2.40 (m, 4H), 2.10 (s, 3H), 1.39 (d, J=6.0 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 388.1 (M+H), Rt 2.1 min 97.5% (Max). HPLC: (Method A) Rt. 2.6 min, 96.3% (Max). Chiral SFC: (Method B) Rt 4.5 min, 100% (Max).

Example 18: 2-(4-((S)-1-((S)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one or 2-(4-((R)-1-((S)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-7,8-dihydropyrido[4,3-d]pyrimidin-5(6H)-one

(191) ##STR00138##

(192) The enantiomers of example 15 were separated by SFC; mobile phase: 20 mM ammonia in methanol, column: Chiracel OJ-H (Method C). The first eluting eluting fraction was concentrated to afford example 18.

(193) Analysis of first eluting fraction (example 18): Yield: 35% (62 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.58 (s, 1H), 7.70 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.88 (d, J=6.8 Hz, 1H), 3.85-3.75 (m, 4H), 3.36-3.23 (m, 3H), 3.26 (d, J=5.6 Hz, 1H), 2.80-2.71 (m, 3H), 2.42-2.33 (m, 4H), 1.38 (d, J=6.0 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 394.2 (M+H), Rt 2.0 min, 99.6% (Max). HPLC: (Method A), Rt 2.6 min, 98.7% (Max). Chiral SFC: (Method C) Rt 2.0 min, 100% (max).

(194) Analysis of second eluting fraction (example 18): Yield: 38% (68 mg, off white solid). .sup.1H NMR: (400 MHz, DMSO-d.sub.6): δ 8.58 (s, 1H), 7.70 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (dd, J=7.6, 1.2 Hz, 1H), 6.68 (s, 1H), 4.85 (d, J=6.8 Hz, 1H), 3.85-3.75 (m, 4H), 3.39-3.34 (m, 3H), 3.30-3.24 (m, 1H), 2.80-2.75 (m, 3H), 2.42-2.34 (m, 4H), 1.38 (d, J=6.0 Hz, 3H), 1.28 (d, J=6.8 Hz, 3H). LCMS: (Method A) 394.2 (M+H), Rt 2.0 min, 99.3% (Max). HPLC: (Method A), Rt 2.6 min, 98.5% (Max). Chiral SFC: (Method C), Rt 2.5 min, 100% (max).

Example 19: 2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-5-(methylsulfonyl)pyrimidine

(195) ##STR00139##

Step 1: 2-chloro-5-(methylsulfonyl)pyrimidine

(196) ##STR00140##

(197) To a stirred solution of 2-chloro-5-(methylthio)pyrimidine (synthesis described in intermediate 8, step 1) (800 mg, 5.0 mmol, Int) in DCM (30 mL) cool to 0° C., m-CPBA (2.58 g, 15.0 mmol) was added, stirred the reaction mixture at rt for 3 h. The reaction mixture was evaporated under vacuum and to the resulting crude water (5 mL) was added. The resulting compound was extracted with EtOAc (50×2 mL) and the combined organic layer was dried over anhydrous sodium sulfate and concentrated. The crude product was purified by column chromatography using eluent Hexane:EtOAc (26%). Yield: 84.21% (3.2 g, yellow gummy). .sup.1H NMR: 400 MHz, DMSO-d6: δ 9.25 (s, 2H), 3.43 (s, 3H). HPLC: (Method A), Rt. 1.48 min, 93.30% (Max).

Step 2: 2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-5-(methylsulfonyl)pyrimidine

(198) To a stirred solution of intermediate 9 (0.3 g, 0.94 mmol) in ACN (3 mL), 2-chloro-5-(methylsulfonyl)pyrimidine (0.2 g, 1.03 mmol) followed by TEA (0.53 mL, 3.75 mmol) were added at RT and the reaction mixture was stirred at RT for 2 h. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 50° C. under vacuum. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with brine solution (20 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (silica gel: 230-400 mesh, eluent: 4% methanol in DCM) to afford the title compound. Yield: 29% (111 mg, pale yellow solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.68 (s, 2H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.6 Hz, 1H), 6.68 (s, 1H), 4.91-4.86 (m, 1H), 3.85-3.83 (m, 4H), 3.40-3.33 (m, 1H), 3.30-3.24 (m, 1H), 3.21 (s, 3H), 2.77-2.68 (m, 1H), 2.56-2.33 (m, 4H), 1.38 (q, J=2.8 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 403.2 (M+H), Rt. 2.1 min, 98.6% (Max). HPLC: (Method A) Rt 2.9 min, 99.4% (Max).

Example 20: imino(methyl)(2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)-λ.SUP.6.-sulfanone

(199) ##STR00141##

Step 1: 2,2,2-trifluoro-N-(methyl(2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl) piperazin-1-yl) pyrimidin-5-yl) (oxo)-λ.SUP.6.-sulfanylidene)acetamide

(200) ##STR00142##

(201) To a stirred solution of intermediate 9 (0.3 g, 0.94 mmol) in ACN (3.0 mL), TEA (0.53 mL, 3.75 mmol) and intermediate 8 (0.3 g, 1.03 mmol) were added at RT and the reaction mixture was stirred at RT for 2 h. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 50° C. under vacuum. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (2×15 mL). The combined organic layer was washed with brine solution (20 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (silica gel: 230-400 mesh, eluent: 25% EtOAc in pet-ether) to afford the title compound. Yield: 66% (0.31 g, pale yellow solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.68 (s, 2H), 7.11 (d, J=7.6 Hz, 1H), 6.80-6.76 (m, 2H), 4.95 (q, J=7.2 Hz, 1H), 4.92-4.11 (m, 1H), 3.98-3.97 (m, 4H), 3.47 (s, 3H), 3.34-3.28 (m, 1H), 2.85-2.79 (m, 1H), 2.55-2.54 (m, 4H), 1.54 (d, J=7.20 Hz, 3H), 1.49 (d, J=6.4 Hz, 3H). LCMS: (Method A) 402.1 (M+H), Rt 2.5 min, 97.1% (Max).

Step 2: Imino(methyl)(2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)-λ.SUP.6.-sulfanone

(202) ##STR00143##

(203) To a stirred solution of 2,2,2-trifluoro-N-(methyl(2-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)pyrimidin-5-yl)(oxo)-λ.sup.6-sulfanylidene)acetamide (0.31 g, 0.61 mmol) in methanol (6.1 mL, 20 V), K.sub.2CO.sub.3 (170 mg, 1.22 mmol) was added and the reaction mixture was stirred for 20 min. Completion of the reaction was monitored by TLC, then after 20 min, the reaction mixture was filtered through celite and the filtrate was concentrated under vacuum. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (2×10 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, gradient: 1-4% methanol in DCM) to afford the title compound. Yield: 19% (74 mg, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 8.66 (s, 2H), 7.11 (d, J=7.6 Hz, 1H), 6.75 (d, J=7.2 Hz, 1H), 6.68 (s, 1H), 4.89-4.86 (m, 1H), 4.25 (s, 1H), 3.83-3.81 (m, 4H), 3.39-3.34 (m, 1H), 3.30-3.24 (m, 1H), 3.08 (s, 3H), 2.77-2.68 (m, 1H), 2.44-2.34 (m, 4H), 1.38 (q, J=6.2 Hz, 3H), 1.28 (d, J=6.4 Hz, 3H). LCMS: (Method A) 402.2 (M+H), Rt 1.9 min, 99.0% (Max). HPLC: (Method A) Rt 2.3 min, 97.9% (Max).

Example 21: 5-(4-(1-((R)-2-methyl-2,3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3,4-thiadiazol-2(3H)-one

Step 1: tert-butyl 4-(hydrazinecarbonothioyl)piperazine-1-carboxylate

(204) ##STR00144##

(205) To a stirred solution of tert-butyl piperazine-1-carboxylate (5.0 g, 26.845 mmol) in THF (50 mL), TEA (11.31 mL, 80.536 mmol) and thiocarbonyldiimidazole (9.57 g, 53.69 mmol) were added at RT and the reaction mixture was stirred for 2 h at RT. After 2 h, hydrazine hydrate (4.03 mL, 80.54 mmol) was added to the reaction mixture and stirred for 2 h at RT. Completion of the reaction was monitored by TLC, then water (50 mL) was added to the resulting mixture and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with brine solution (20 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was forwarded as such to the next step without any further purification. Yield: 92% (4.5 g, off white solid.). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 9.12 (s, 1H), 4.74 (bs, 2H), 3.71 (d, J=4.1 Hz, 4H), 2.80-2.78 (m, 4H) 1.41 (s, 9H). LCMS: (Method A) 261.0 (M+H), Rt. 2.0 min, 95.6% (Max).

Step 2: tert-butyl 4-(5-oxo-4,5-dihydro-1,3, 4-thiadiazol-2-yl)piperazine-1-carboxylate

(206) ##STR00145##

(207) To the stirred solution of tert-butyl 4-(hydrazinecarbonothioyl) piperazine-1-carboxylate (4.5 g, 13.46 mmol) in DCM (35 mL), TEA (6.60 mL, 40.39 mmol) and carbonyldiimidazole (8.3 g, 40.39 mmol) were added at RT for 4 h. Completion of the reaction was monitored by TLC, then water (25 mL) was added to the resulting mixture and the aqueous layer was extracted with EtOAc (2×25 mL). The combined organic layer was washed with brine solution (25 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (silica gel: 230-400 mesh, eluent: 1-2% methanol in DCM) to afford the title compound. Yield: 58% (2.8 g, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 11.79 (s, 1H), 3.38-3.36 (m, 4H), 3.18-3.16 (m, 4H), 1.41 (s, 9H). LCMS: (Method A) 231.0 (M-t-butyl), Rt. 2.4 min, 99.9% (Max).

Step 3: 5-(piperazin-1-yl)-1, 3, 4-thiadiazol-2(3H)-one hydrochloride

(208) ##STR00146##

(209) To a stirred solution of tert-butyl 4-(hydrazinecarbonothioyl) piperazine-1-carboxylate (2.8 g, 5.069 mmol) in dry 1,4-dioxane (10 mL) at 0° C., HCl solution in dioxane (20 mL, 4M) was added dropwise and the reaction mixture was stirred for 4 h at RT. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated under vacuum to afford the tittle compound. Yield: 86% (1.81 g, off white solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 11.96 (s, 1H), 9.51 (s, 2H), 3.45 (t, J=4.8 Hz, 4H), 3.16 (bs, 4H). LCMS: (Method A) 187.1 (M+H), Rt. 0.5 min, 90.7% (Max).

Step 4: 5-(4-(1-((R)-2-methyl-2, 3-dihydrobenzofuran-6-yl)ethyl)piperazin-1-yl)-1,3, 4-thiadiazol-2(3H)-one

(210) ##STR00147##

(211) To a stirred solution of 5-(piperazin-1-yl)-1,3,4-thiadiazol-2(3H)-one dihydrochloride (0.51 g, 1.95 mmol)) in dry DMF (3.5 mL), TEA (1.0 mL, 7.11 mmol) and intermediate 4 (350 mg, 1.77 mmol) were added at Rt and the reaction mixture was heated at 80° C. overnight. Completion of the reaction was monitored by TLC, then the reaction mixture was evaporated at 55° C. under vacuum. To the resulting mixture, water (2 mL) was added and the aqueous layer was extracted with EtOAc (3×10 mL). The combined organic layer was washed with brine solution (10 mL), dried over anhydrous Na.sub.2SO.sub.4 and concentrated under vacuum. The resulting crude material was purified by flash chromatography (Biotage Isolera, eluent: 4-5% methanol in DCM) to afford the title compound. Yield: 30% (184 mg, pale yellow solid). .sup.1H NMR (400 MHz, DMSO-d.sub.6): δ 11.70 (s, 1H), 7.11 (d, J=7.6 Hz, 1H), 6.73 (d, J=7.6 Hz, 1H), 6.66 (s, 1H), 4.91-4.85 (m, 1H), 3.39-3.33 (m, 1H), 3.30-3.24 (m, 1H), 3.17-3.12 (m, 4H), 2.77-2.68 (m, 1H), 2.48-2.35 (m, 4H), 1.38 (d, J=6.4 Hz, 3H), 1.26 (d, J=6.4 Hz, 3H). LCMS: (Method A) 347.1 (M+H), Rt 2.0 min, 96.2% (Max). HPLC: (Method A) Rt 2.5 min, 94.8% (Max).

Example B01: Human O-GlcNAcase Enzyme Inhibition Assay

(212) 5 μl of the appropriate concentration of a solution of inhibitor in Mcllvaine's Buffer (pH 6.5) in 2% DMSO (for a dose response curve calculation) is added into each well of a 384-well plate (Greiner, 781900). Then, 20 nM of His-Tagged hOGA and 10 μM of FL-GlcNAc (Fluorescein mono-beta-D-(2-deoxy-2-N-acetyl) glucopyranoside; Marker Gene Technologies Inc, M1485) were added to the 384-well plate for a final volume of 20 μl. After incubation for 60 min at room temperature, the reaction was terminated by the addition of 10 μL of stop buffer (200 mM glycine, pH 10.75). The level of fluorescence (λ.sub.exc 485 nm; (λ.sub.emm 520 nm) was read on a PHERAstar machine. The amount of fluorescence measured was plotted against the concentration of inhibitor to produce a sigmoidal dose response curve to calculate an IC.sub.50. All individual data was corrected by subtraction of the background (Thiamet 3 uM=100% inhibition) whilst 0.5% DMSO was considered as the control value (no inhibition).

Example B02: Pharmacodynamic Model: Total Protein O-GlcNAcylation Immunoassay (RL2 mAb, Meso Scale Electrochemiluminescence (ECL) Assay)

(213) The test compound was administered orally to C57BL/6J mice. At defined time intervals after compound administration, typically a time ranging between 2 and 48 hours, preferably between 4 and 24 hours, mice were sacrificed by decapitation for blood collection and forebrain dissection. Right brain hemispheres were placed in 2 ml Precellys tubes, snap frozen in dry ice and stored at -80° C. Left hemispheres were placed in 2 ml Eppendorf tubes, snap frozen in dry ice and stored at -80° C. until further processing. Blood samples were collected in Sarstedt tubes containing 35 IU of Heparin and kept at 4° C. After centrifugation for 10 min at 3800 xg, 4° C., 50 μL of plasma from each sample was transferred to a 1.5 ml Eppendorf tube and stored at −80° C.

(214) For the preparation of soluble brain protein for the immunoassay the hemispheres were homogenized in ice-cold Cytobuster reagent (71009—Merck Millipore) buffer with protease inhibitor cocktail. After centrifugation for 15 min at 17000 xg at 4° C. the supernatants were transferred into polycarbonate tubes (1 ml). The supernatants were cleared by centrifugation for 1 h. at 100000 xg, 4° C., and the protein concentrations were determined by using the BCA kit (23227—Pierce, Rockford, Ill.) according to the manufacturer's instructions.

(215) Total Protein O-GlcNAcylation Immunoassay:

(216) Samples were randomised and 120 μg/ml (25 μl/well) of soluble brain protein was directly coated on a Multi-array 96-well high bind plate (L15XB-3 High bind—Meso Scale Discovery) overnight at 4° C. After washing (3× with PBS-T buffer), the plate was blocked with MSD blocker A solution for 1 h. at room temperature (RT) under agitation. After washing (3× with PBS-T buffer), the plate was incubated with 0.1 μg/ml of a mouse monoclonal antibody directed against O-GlcNAc moieties (RL2; MA1-072—Thermo Scientific) for 1 h. at RT under agitation. For the ECL assay, after washing (3× with PBS-T buffer), 1 μg/ml of a SULFO-TAG™ labeled anti-mouse secondary antibody (Meso Scale Discovery) was added and the plate was incubated for 1 h. at RT under agitation and protected from light. After washing (3× with PBS-T buffer), 150 μl/well of 1× Read Buffer T was added to the plates before reading on a Sector Imager 6000 (Meso Scale Discovery).

Example B03: Pharmaceutical Preparations

(217) (A) Injection vials: A solution of 100 g of an active ingredient according to the invention and 5 g of disodium hydrogen phosphate in 3 l of bi-distilled water was adjusted to pH 6.5 using 2 N hydrochloric acid, sterile filtered, transferred into injection vials, lyophilized under sterile conditions and sealed under sterile conditions. Each injection vial contained 5 mg of active ingredient.

(218) (B) Suppositories: A mixture of 20 g of an active ingredient according to the invention was melted with 100 g of soy lecithin and 1400 g of cocoa butter, poured into moulds and allowed to cool. Each suppository contained 20 mg of active ingredient.

(219) (C) Solution: A solution was prepared from 1 g of an active ingredient according to the invention, 9.38 g of NaH.sub.2PO.sub.4.2H.sub.2O, 28.48 g of Na.sub.2HPO.sub.4.12H.sub.2O and 0.1 g of benzalkonium chloride in 940 ml of bi-distilled water. The pH was adjusted to 6.8, and the solution was made up to 1 l and sterilized by irradiation. This solution could be used in the form of eye drops.

(220) (D) Ointment: 500 mg of an active ingredient according to the invention were mixed with 99.5 g of Vaseline under aseptic conditions.

(221) (E) Tablets: A mixture of 1 kg of an active ingredient according to the invention, 4 kg of lactose, 1.2 kg of potato starch, 0.2 kg of talc and 0.1 kg of magnesium stearate was pressed to give tablets in a conventional manner in such a way that each tablet contained 10 mg of active ingredient.

(222) (F) Coated tablets: Tablets were pressed analogously to EXAMPLE E and subsequently coated in a conventional manner with a coating of sucrose, potato starch, talc, tragacanth and dye.

(223) (G) Capsules: 2 kg of an active ingredient according to the invention were introduced into hard gelatin capsules in a conventional manner in such a way that each capsule contained 20 mg of the active ingredient.

(224) (H) Ampoules: A solution of 1 kg of an active ingredient according to the invention in 60 l of bi-distilled water was sterile filtered, transferred into ampoules, lyophilized under sterile conditions and sealed under sterile conditions. Each ampoule contained 10 mg of active ingredient.

(225) (I) Inhalation spray: 14 g of an active ingredient according to the invention were dissolved in 10 l of isotonic NaCl solution, and the solution was transferred into commercially available spray containers with a pump mechanism. The solution could be sprayed into the mouth or nose. One spray shot (about 0.1 ml) corresponded to a dose of about 0.14 mg.

Example B04: Protein Binding in Mice Plasma Using Rapid Equilibrium Dialysis

(226) Materials CD1 Mice Plasma: pooled male, K2-EDTA (MSEPLEDTA2, Bioreclammation, USA Phosphate Buffered Saline (1×PBS), pH 7.4, 100 mM (Sigma, Cat No. P4417) RED inserts (Pierce, Cat No. 9006, 8 kDa MWCO) Sample Analysis: LC-MS/MS

(227) Methods

(228) Preparation of DMSO Stock Solution

(229) From 20 mM DMSO stock solutions of reference and test compounds, 1 mM DMSO intermediate working solutions are prepared. From 1 mM intermediate working solutions, 100 μM DMSO working solutions are prepared.

(230) Sample Preparation Procedure:

(231) Selected plasma is brought from −20° C. to 37° C. using water bath before its use. Test solution is prepared by adding the DMSO working solution of the reference or test compound (2 μL; 100 μM) to the selected plasma (198 μL). Spiked plasma (200 μl) is transferred to sample compartment of RED insert placed in the teflon plate. 350 μl of 1×PBS is added in the buffer compartment of RED insert. The teflon plate is covered with sealing mat and agitated at 37° C. for 5 hours at 500 RPM in a Thermomixer. After incubation time, an aliquot of plasma (50 μl) from sample compartment is mixed with blank 1×PBS (50 μl). Similarly, an aliquot of buffer (50 μl) from buffer compartment is mixed with blank plasma (50 μl). Quenching solution (200 μL, acetonitrile containing internal standard tolbutamide (0.5 μg/mL)) is added and the resulting solutions are mixed using a vortex mixer and centrifuged (Eppendorf 5415, 13792 g). Supernatants are analyzed using a Mass Spectrometer. The sample (supernatant fraction, 5 μL) is injected into the LC-MS/MS instrument.

(232) Chromatographic Conditions:

(233) LC-MS/MS: API 4000 LC-MS/MS

(234) Software: Analyst Version 1.6.1

(235) Column Phenomenex Synergy 30*4.6*5μ

(236) Column Oven: 40° C.

(237) Mode: ESI Positive

(238) Injection volume: 5 μl

(239) Flow Rate: 1000 μL/mL

(240) Buffer: 0.1% Formic acid in Water

(241) Method: Isocratic Method/Gradient

(242) Composition: A) 0.1% Formic acid in Water B) 0.1% Formic acid in Methanol

(243) TABLE-US-00003 Mobile Mobile Time (Sec) Flow (μL) Phase A Phase B 0.01 1000 10 90 0.4 1000 10 90 0.8 1000 90 10 1.5 1000 90 10 1.8 1000 10 90 2.5 1000 10 90

(244) Results Calculation

(245) After the concentration of free drug and total drug has been determined by LCMS/MS, percent plasma protein binding can be calculated as follows:

(246) $\%\mathrm{fraction}\mathrm{unbound}=\frac{\mathrm{Drug}\mathrm{concentration}\mathrm{in}\mathrm{buffer}\mathrm{after}5\mathrm{hours}}{\mathrm{Drug}\mathrm{concentration}\mathrm{in}\mathrm{plasma}\mathrm{after}5\mathrm{hours}}\times 100$

(247) Following this protocol, % fraction unbound in plasma from different species can be also measured.

Example B05: Determination of In Vitro Intrinsic Clearance (Cl.SUB.int.-In Vitro) with Mouse, Rat and Human Liver Microsomes

(248) In this assay, test compounds are incubated with liver microsomes from mouse, rat and human, and rate of disappearance of drug is determined using LC-MS/MS. Conditions used in the assay are summarized below:

(249) Materials CD-1 Mice liver microsomes, pooled male (Life Technologies, Cat No. MSMC-PL) (20 mg/ml) SD Rat liver microsomes, pooled male (Life Technologies, Cat No. RTMCL-PL) (20 mg/ml) Human liver microsomes, pooled mixed gender (Life Technologies, Cat No. HMMC-PL) (20 mg/ml) NADPH (SRL Mumbai, Cat No. 99197) Verapamil (Sigma, Cat No. V4629) Atenolol (Sigma, Cat No. A7655) Tolbutamide (Sigma Cat. No. T0891) Assay buffer: 50 mM potassium phosphate buffer, pH 7.4 Test & reference compounds: DMSO stock solutions (10 mM concentration) are prepared and stored at room temperature. An intermediate 1 mM solution of test or reference compounds is prepared by mixing 10 μL of 10 mM DMSO stock with 90 μL of DMSO. The contents are mixed vigorously in a vortex mixer.

(250) Methods

(251) Preparation of Working Solutions of Test and Reference Compounds:

(252) Working solution (100 μM concentration) is prepared by mixing 10 μL of 1 mM DMSO solution of test or reference compounds with 90 μL of assay buffer. The mixture is mixed vigorously in a vortex mixer. This resulting solution is containing 10% of DMSO. For the metabolic stability assay, 10 μL of this 100 μM working solution is added to a final assay volume of 1 mL, yielding final test concentration of 1 μM and DMSO concentration of 0.1%.

(253) Metabolic Stability Assay

(254) Metabolic stability assay is done in a final volume of 1 ml in 50 mM assay buffer, potassium phosphate buffer, pH 7.4. Assay is carried out in duplicates (n=2). A mixture containing 955 μL of assay buffer, 25 μL of liver microsomes and 10 μL of 100 μM test compound solution is pre-incubated for 10 minutes in a water-bath maintained at 37° C. After pre-incubation, reaction is started by adding 10 μL of 100 mM NADPH solution. The solution is mixed and incubated at 37° C. in a water-bath. The final concentration of the different components in the assay is: DMSO 0.1%, test compound 1 μM, liver microsome protein 0.5 mg/ml and NADPH 1 mM.

(255) Aliquots (100 μL) are taken at various time-points (0, 5, 15, 30 and 45 minutes) and quenched with 100 μL of acetonitrile containing tolbutamide (500 ng/mL) as internal standard. Samples are mixed using a vortex mixer and centrifuged at 4000 rpm for 10 minutes (Eppendorf 5810R, 3000 g). The supernatants (5 μL) are transferred to 96 well plates and submitted for LC-MS/MS analysis.

(256) Separate incubations in the same assay mixture, but in the absence of NADPH, are run in parallel as control for compound stability. This control assay is carried out in duplicates (n=2). After pre-incubation, addition of NADPH is omitted and replaced with 10 μL of assay buffer. The final assay volume is 1 mL and aliquots (100 μL) are withdrawn and processed for analysis as described for metabolic stability assay.

(257) LC-MS/MS Conditions (Generic Method)

(258) LC-MS/MS: API Sciex 4000 with Nexera™ UHPLC

(259) Software: Analyst Version 1.6.1

(260) Column: Phenomenex kinetex C18 50×3.0 mm, 2.6p

(261) Column Oven: 40° C.

(262) Mode: ESI Positive

(263) Injection volume: 5 μl

(264) Flow Rate: 1000 μL/mL

(265) Buffer: 0.1% Formic acid in Water

(266) Method: Isocratic Method/Gradient

(267) Composition: A) 0.1% Formic acid in Water B) 0.1% Formic acid in Methanol

(268) TABLE-US-00004 Mobile Mobile Time (Sec) Flow (μL) Phase A Phase B 0.01 1000 10 90 0.4 1000 10 90 1 1000 90 10 1.5 1000 90 10 1.8 1000 10 90 3 1000 10 90

(269) Results Calculation

(270) From LC-MS/MS data, amount of drug remaining at different time points was determined (% PCR). The logarithm of % PCR was plotted against time to get the slope value. From the slope value, in vitro T.sub.1/2 was determined. In vitro intrinsic clearance (Cl.sub.int) was calculated using the following formulae:

(271) ${\mathrm{CL}}_{\mathrm{int}}=\frac{0.693}{\mathrm{In}\mathrm{vitro}{t}_{1/2}}\times \frac{\mathrm{Volume}\mathrm{of}\mathrm{incubation}}{\mathrm{mg}\mathrm{of}\mathrm{microsomal}\mathrm{protein}}\mathrm{In}\mathrm{vitro}{t}_{1/2}=\frac{0.693}{K_{\mathrm{el}}}$

(272) Where K.sub.el is Elimination Constant (slope)

(273) Methods for treating the diseases mentioned in this specification, such as tauopathy, by administering one or more of the compounds of the present invention to a patient in need thereof are also object of this invention.

(274) If chemical bonds in the structures above are drawn as follows:

(275) they indicate a defined, i.e. R or S, stereochemistry at at least one of the atoms to which they are attached to.

(276) This is exemplified below, wherein the structure

(277) ##STR00148##
is representing only one of the two possible diastereoisomers,

(278) ##STR00149##
i.e. a single individual chemical structure as opposed to a mixture of diastereoisomers.