AMINOTETRAHYDROPYRAN DERIVATIVE USED AS DIPEPTIDYL PEPTIDASEIV INHIBITOR

Abstract

Provided is an Aminotetrahydropyran derivative represented by general formula (I), a preparation method for the derivative, a pharmaceutical composition containing the derivative, and the use of the derivative to prepare a therapeutic agent, especially a dipeptidyl peptidase-IV inhibitor.

##STR00001##

Claims

1. A compound of formula (I): ##STR00054## Wherein, Ar is a substituted or unsubstituted aryl, heteroaryl; R.sub.1 is a hydrogen, a substituted or unsubstituted alkyl; R.sub.2a and R.sub.2b are each independently selected from hydrogen, or R.sub.2a and R.sub.2b are each independently selected from substituted or unsubstituted alkyl, alkoxy, cycloalkyl, heterocyclylalkyl; or R.sub.2a and R.sub.2b form heterocyclylalkyl with the nitrogen atom attached to them, and the heterocyclylalkyl can be optionally substituted; A is selected from: ##STR00055## R.sub.3a and R.sub.3b are each independently selected from hydrogen, substituted or unsubstituted C.sub.1-10 alkyl; R.sub.4 is: ##STR00056## X is CR.sub.8 or N; wherein 0-3 R.sub.7 may be present, and each R.sub.7 is independently oxo, halogen, substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, or two or more R.sub.7 form brideged alkyls; W is CR.sub.8, O, or N; R.sub.6 is selected from H, hydroxyl, or R.sub.6 is selected from substituted or unsubstituted C.sub.1-8 alkyl, C.sub.1-8 alkyl-R.sub.9, C.sub.3-14 cycloalkyl, 3-14 membered heterocyclylalkyl, C(O)—C.sub.1-8 alkyl, C.sub.1-8 halogen substituted alkyl, C.sub.1-8 alkyl hydroxyl, C(O)NR.sub.9R.sub.10, C.sub.1-8 cyano alkyl, C(O)R.sub.9, C.sub.0-8 alkyl-C(O)—C.sub.0-8 alkyl-NR.sub.9R.sub.10, C.sub.0-8 alkyl-C(O)OR.sub.9, NR.sub.9R.sub.10, SO.sub.2—C.sub.1-8 alkyl, C.sub.1-8 alkyl-C.sub.3-14 cycloalkyl, C(O)—C.sub.1-8 alkyl-C.sub.3-14 cycloalkyl, C.sub.1-8 alkoxy; R.sub.8 is a hydrogen or halogen; R.sub.9 and R.sub.10 are each independently selected from H, C.sub.1-8 alkyl, C.sub.3-14 cycloalkyl, 3-14 membered heterocyclylalkyl, C.sub.6-14 aryl, 5-14 membered heteroaryl, alkoxy, C(O)C.sub.1-4alkyl, C.sub.1-8 alkylamino, C.sub.1-6 alkyls hydroxyl; m is 0, 1 or 2; n is 0, 1 or 2; R.sub.5 is selected from H, halogen, cyano, amino, nitro, or R.sub.5 is selected from substituted or unsubstituted C.sub.1-10 alkyl, C.sub.1-10 alkoxy, C.sub.2-10 alkenyl, (CH.sub.2).sub.p-aryl, (CH.sub.2).sub.p-heteroaryl, (CH.sub.2).sub.p-cycloalkyl, (CH.sub.2).sub.p-heterocyclylalkyl, (CH.sub.2).sub.p—NR.sub.11R.sub.12, (CH.sub.2).sub.p—SO.sub.2NR.sub.11R.sub.12, (CH.sub.2).sub.p—SO.sub.2R.sub.13, (CH.sub.2).sub.p—NR.sub.11SO.sub.2R.sub.13, (CH.sub.2).sub.p—OR.sub.13, (CH.sub.2).sub.p—OCOR.sub.13, (CH.sub.2).sub.p—OCONR.sub.11R.sub.12, (CH.sub.2).sub.p—CONR.sub.11R.sub.12, (CH.sub.2).sub.p—NR.sub.13CONR.sub.11R.sub.12, (CH.sub.2).sub.p—COOH, (CH.sub.2).sub.p—COR.sub.13, (CH.sub.2).sub.p—CO.sub.2C.sub.1-6 alkyl, (CH.sub.2).sub.p—NR.sub.11COOR.sub.13; wherein, R.sub.11 and R.sub.12 are each independently selected from hydrogen, (CH.sub.2).sub.q-phenyl, (CH.sub.2).sub.q—C.sub.3-8 cycloalkyl, C.sub.1-6 alkyl, wherein alkyl is optionally substituted by 1-5 substituents selected from fluorine or hydroxyl, wherein phenyl and cycloalkyl are optionally substituted by 1-5 substituents independently selected from halogen, hydroxyl, trifluoromethyl, C.sub.1-6 alkyl or C.sub.1-6 alkoxy; or R.sub.11 and R.sub.12, together with the nitrogen atom they are attached to, form a heterocyclic ring selected from piperidine, piperazine, morpholine, pyrrole or azetidine, wherein the heterocyclic ring is optionally substituted by 1-3 substituents independently selected from halogen, hydroxyl, C.sub.1-6 alkyl or C.sub.1-6 alkoxy; each R.sub.13 is independently C1-6 alkyl, wherein the alkyl is optionally substituted by 1-5 substituents selected from fluorine or hydroxyl; p is 0, 1, 2, 3, 4, 5 or 6; q is 0, 1 or 2; or the pharmaceutical acceptable salts, hydrates, solvates or stereisomers thereof.

2. The compound according to claim 1, wherein, Ar is a phenyl that is optionally substituted by 1-5 R.sub.14; each R.sub.14 is independently selected from halogen, hydroxyl, cyano, nitro, nitroso, amino, imino, carboxyl, sulfydryl or each R.sub.14 is independently selected from substituted or unsubstituted alkyl, acyl, acylamino, ester group, acylester group, phenoxy, benzyl, benzyloxy, sulfonyl, sulfinyl, cycloalkyl, heterocyclylalkyls, alkenyl, alkynyl, alkoxy, allyloxy, alkylamino, aryl, heteroaryl.

3. The compound according to claim 2, wherein, Ar is a phenyl that is optionally substituted by 1-3 substituents independently selected from F, Cl, Br, I, —CH.sub.3, —CF.sub.3 and —OCF.sub.3.

4. The compound according to claim 3, wherein, Ar is 2,5-difluorophenyl or 2,4,5-trifluorophenyl.

5. The compound according to claim 1, wherein, R.sub.2a and R.sub.2b are each independently selected form hydrogen, C.sub.1-10 alkyl, alkoxy, C.sub.3-14 cycloalkyl, 3-14 membered heterocyclylalkyl; wherein, alkyl is optionally substituted by 1-6 substituents that are independently selected from halogen, hydroxyl, trifluoromethyl; alkoxyl is optionally substituted by 1-6 substituents that are independently selected from halogen or hydroxyl; cycloalkyl is optionally substituted by 1-3 substituents that are independently selected from halogen, hydroxyl, cyano, nitro, carboxyl, C.sub.1-6 alkyl, C.sub.1-6 alkyloxycarbonyl or C.sub.1-6 alkoxyl, wherein alkyl and alkoxyl can be substituted by 1-5 fluorine; heterocyclylalkyl is optionally substituted by 1-3 substituents that are independently selected from oxo, halogen, hydroxyl, cyano, nitro, carboxyl, C.sub.1-6 alkyl, C.sub.1-6 alkyloxycarbonyl or C.sub.1-6 alkoxyl; or R.sub.2a and R.sub.2b, together with the nitrogen atom they are attached to, form a heterocyclic ring that is selected from piperidine, piperazine, morpholine, pyrrole or azetidine, wherein the heterocyclic ring is optionally substituted by 1-3 substituents that are independently selected from halogen, hydroxyl, C.sub.1-6 alkyl or C.sub.1-6 alkoxyl, wherein each alkyl and alkoxyl are optionally substituted by 1-5 fluorine.

6. The compound according to claim 5, wherein, R.sub.2a and R.sub.2b are each independently selected from hydrogen, C.sub.1-6 alkyl that is optionally substituted by 1-3 fluorine or hydroxyl; or R.sub.2a and R.sub.2b, together with the nitrogen atom they are attached to, form a heterocyclic ring that is selected from piperidine, piperazine, morpholine, pyrrole or azetidine.

7. The compound according to claim 6, wherein, R.sub.2a and R.sub.2b are hydrogens.

8. The compound according to claim 1, wherein, R.sub.3a and R.sub.3b are each independently selected from hydrogen, C.sub.1-6 alkyl that is optionally substituted by 1-6 fluorine.

9. The compound according to claim 8, wherein, R.sub.3a and R.sub.3b are hydrogens.

10. The compound according to claim 1, wherein, A is: ##STR00057##

11. The compound according to claim 10, wherein, R.sub.5 is hydrogen.

12. The compound according to claim 1, wherein, R.sub.4 is: ##STR00058## wherein 0-2 R.sub.7 may be present, and R.sub.7 is oxo, or two R.sub.7 form brideged alkyl; W is CR.sub.8, O, or N; R.sub.6 is selected from H, hydroxyl, or R.sub.6 is selected from substituted or unsubstituted C.sub.1-8 alkyl, C.sub.3-8 cycloalkyl, 3-8 membered heterocyclylalkyl, C(O)—C.sub.1-6 alkyl, C(O)NR.sub.9R.sub.10, C(O)R.sub.9, NR.sub.9R.sub.10, SO.sub.2—C.sub.1-8alkyl; R.sub.8 is a hydrogen or halogen; R.sub.9 and R.sub.10 are each independently selected from H, C.sub.1-6 alkyl, C.sub.3-8 cycloalkyl, 3-8 membered heterocyclylalkyl; m is 0, 1, or 2; n is 0, 1 or 2.

13. The compound according to claim 1, wherein, the compound of formula I is shown as structure formula Ia or Ib, which has the shown absolute stereochemical configuration on the two * marked carbon atoms that are formed stereoscopically: ##STR00059##

14. The compound according to claim 13, wherein, the compound of formula I is shown as structure formula Ia, which has the shown absolute stereochemical configuration on the two * marked carbon atoms that are formed stereoscopically: ##STR00060##

15. The compound according to claim 14, wherein, the compound of formula Ia is shown as structure formula Ic and Id, which have the shown absolute stereochemical configuration on the two * marked carbon atoms that are formed stereoscopically: ##STR00061##

16. The compound according to claim 15, wherein, the compound of formula Ia is shown as structure formula Ic, which has the shown absolute stereochemical configuration on the two * marked carbon atoms that are formed stereoscopically: ##STR00062##

17. The compound according to claim 16, wherein A is selected from: ##STR00063##

18. The compound according to claim 17, wherein R.sub.5 is H.

19. The compound according to claim 1, which is selected from the following compounds: ##STR00064## ##STR00065## ##STR00066##

20. A method for treating disease, disorder or syndrome related to inhibition of DPP-4 comprising administering the compound according to claim 1 or the pro-drugs thereof or the pharmaceutical compositions comprising the compound of formula (I) or the pro-drugs thereof and the pharmaceutically acceptable excipients to an individual in need thereof; preferably, the disease, disorder or syndrome is selected from insulin resistance, hyperglycemia, type 2 diabetes, wherein the individual comprises human.

21. (canceled)

Description

EMBODIMENTS

[0062] The method for preparing the compounds of the present invention:

[0063] The compounds of formula (I) can be prepared according to process 1, wherein every substituent is defined as in SUMMARY OF THE INVENTION:

Process 1

[0064] ##STR00016##

[0065] In the presence of intermediate III, reagents such as sodium borohydride, decaborane or sodium triacetoxyborohydride are used in suitable solvents such as tetrahydrofuran, methanol, methylbenzene, pyridine, DMF or DMSO to provide intermediate IV through the reductive amination of the intermediate II. The reaction is carried out under the presence of Lewis acids such as titanium tetrachloride or titanium tetraisopropylate. The reaction can also be accelerated by adding acid such as acetic acid. In certain circumstance, the intermediate III can be a salt, such as trifluoroacetate or hydrochloride, base such as N,N-diisopropylethylamine or triethylamine can be conveniently added to the reaction mixture. Then deprotection is carried out, such as for Boc, trifluoroacetic acid or hydrochloric acid-methanol solution is used, or for Fmoc, triethylamine, diethylamine, piperidine or morpholine is used for a reaction in DMF, NMP or acetonitrile, then R.sub.a and R.sub.b groups (when R.sub.a and R.sub.b are both not hydrogen) are introduced via a suitable method (such as under basic condition, the intermediate IV is reacted with R.sub.aCl and/or R.sub.bCl) to obtain the compound of formula (I).

Process 2

[0066] ##STR00017##

[0067] The intermediate II can be obtained by methods known by those skilled in the art. Nitroalcohol b is obtained via aldehyde a and nitromethane under the presence of a base, then the obtained nitroalcohol b is treated with a oxidizing agent such as Dess-martin, to obtain nitroketone c, d is prepared through the reaction of nitroketone c and 3-iodo-2-(iodomethyl) prop-1-ene under heating. The obtained d is reduced by a reducing agent such as sodium borohydride to obtain two products: cis-product and trans-product, wherein the cis-product ban be easily transformed into the trans-product by isomerization of a base such as DBU. The obtained trans products e1 and e2 are separated through HPLC via a chiral cel to obtain e2. Then, e2 is reduced by zinc and acid such as hydrochloric acid to obtain aminopyran f, g is produced by the protection of amino by a protecting group such as Boc. Dihydroxyl compound h is obtained by the treatment of oxidizing agents such as osmium tetroxide and N-methylmorpholine N-oxide, then the intermediate IIa is obtained by the oxidizing of sodium periodate.

Process 3

[0068] ##STR00018##

[0069] The intermediate III can be prepared by a general process 3. The pyrrolidinol i protected by Boc or other protecting agent can be transformed into pyrrolidone j through oxidization such as Swern oxidization. Under the presence of DMF-DMA, k is provided by j under heating, then k is used to obtain intermediate I in a suitable solvent such as ethanol with the presence of hydrazine under heating. I is reacted with L-R.sub.2, after L leaves, the intermediates IIIa and IIIb are provided via deprotection under a suitable condition, and IIIa and IIIb ban be separated by methods known by those skilled in the art such as column chromatography.

[0070] The purposes of the following examples are to describe specific embodiments of the invention, but not limit the extent of the description and claims. Those skilled in the art can understand that the raw materials can be different, and the compounds emcompassed by the present invention can be produced via additional steps as shown in the following examples. The following examples are only provided for illustrating purpose, they are not intended to or should be understood in any ways to limit the present invention. Those skilled in the art should realize that changes and modifications without violating the spirit or extent of the present invention can be accepted.

Abbreviation List

[0071] DMF: N,N-dimethylformamide [0072] DMSO: dimethyl sulfoxide [0073] Boc: t-butyloxycarbonyl [0074] Fmoc: fluorene methoxyl carbonyl acyl [0075] NMP: N-methyl pyrrolidone [0076] DBU: 1,8-diazacyclo[5,4,0]hendecene-7 [0077] HPLC: High Performance Liquid Chromatography [0078] DMF-DMA: N,N-dimethylformide dimethyl acetal [0079] DIPEA: N,N-diisopropylethylamine [0080] NMO: N-methyl-N-morpholine oxide

Example 1

[0081] ##STR00019##

Preparation of compound 1: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(morpholine sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

A. Preparation of Intermediate

[0082] ##STR00020##

Step 1. Preparation of 1-(2,5-difluorophenyl)-2-nitroethanol

[0083] ##STR00021##

[0084] At 5° C., 50 mL methanol solution of 2,5-difluorobenzaldehyde (50 g, 0.35 mol) and nitromethane (22.4 mL, 0.414 mol) were added to the methanol (214 mL) solution of sodium hydroxide (1N, 428 mL) (more than 1 h), after the addition, glacial acetic acid (24 mL) was added to neutralize the reaction solution, then diethyl ether was added, the organic layer was washed with saturated sodium carbonate (30 mL) and saturated salt water (30 mL), the organic layer was dried over anhydrous magnesium sulfate and was concentrated to obtain 1-(2,5-difluorophenyl)-2-nitroethanol, and the product can be used in step 2 without further purification.

Step 2. Preparation of 2-nitro-1-(2,5-difluorophenyl) ethanone

[0085] At 10° C., within 30 minutes, the dess-martin periodinane (184 g) was added into the dichloromethane solution of nitroethanol (68.1 g) prepared in step 1 in three batches. Continuously stirred for 24 h, then the reaction mixture was poured to the mixing solution of sodium bicarbonate (441 g) and sodium thiosulfate (489 g) in water (4.2 L). HCl (6N, 1.5 L) was used to neutralize the aqueous layer until no more bubble was generated, extracted with dichloromethane, washed one time with sodium bicarbonate solution. The organic layer was dried over anhydrous magnesium sulfate then combined, filtered and evaporated to dryness, purified through chromatography (silica gel, petroleum ether:ethyl acetate 10:1-6:1 gradient elute) to obtain the desired nitroketone 54 g. .sup.1H NMR (400 MHz, CDCl.sub.3) δ 7.74-7.70 (m, 1H), 7.43-7.37 (m, 1H), 7.28-7.22 (m, 1H), 5.82 (d, J=3.6 Hz, 2H).

Step 3. Preparation of 3-iodo-2-(iodomethyl)-isopropyl-1-ene

[0086] ##STR00022##

[0087] The reaction solution of 3-chloro-2-(chloromethyl)prop-1-ene (5.75 mL, 54.7 mmol) and sodium iodide (45 g, 301 mmol) in acetone (400 mL) was stirred at room temperature for 20 h, and concentrated to dry under vacuum, then dispersed in dichloromethane and water. The organic layer was dried over anhydrous sodium sulfate, filtered, evaporated to dryness to obtain 3-iodo-2-(iodomethyl)prop-1ene, which is a light red oily compound.

Step 4. Preparation of 6-(2,5-difluorophenyl)-3-methylene-5-nitro-3,4-dihydro-2H-pyran

[0088] ##STR00023##

[0089] 3-iodo-2-(iodomethyl)-isoprop-1-ene (16.8 g, 54.7 mmol) was dissolved in 50 mL DMF, 20 mL DIPEA was added, then 2-nitro-1-(2,5-difluorophenyl) ethanone (10 g, 49.7 mmol) was added slowly drop by drop, then was stirred for 2 h at room temperature after the addition, 400 mL water was added, extracted with ethyl acetate for three times, the organic layers were combined and dried over anhydrous sodium sulfate, 3 g product was obtained by column chromatography (petroleum ether:dichloromethane 20%-30% gradient elute). .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ7.50-7.29 (m, 3H), 5.41 (brs, 1H), 5.34 (brs, 1H), 4.74 (s, 2H), 3.58 (brs, 2H)

Step 5. Preparation of (2R, 3S)-2-(2,5-difluorophenyl)-5-methylene-3-nitrotetrahydro-2H-pyran

[0090] ##STR00024##

[0091] Silica gel (100-200 mesh) 58 g and sodium borohydride (5.2 g, 136.6 mmol) were added to the solution of 6-(2,5-difluorophenyl)-3-methylene-5-nitro-3,4-dihydro-2H-pyran (9.1 g, 35.96 mmol) in chloroform (480 ml) and isopropanol (90 ml), stirred at room temperature overnight. Then diluted hydrochloric acid (69 mL, 2N) was added slowly to quench the reaction, filtered. The silica gel was washed with ethyl acetate. The organic layer was washed with sodium bicarbonate, dried over anhydrous sodium sulfate, and concentrated to dry under vacuum, then subjected to column chromatography (petroleum ether:diethyl ether=16:1 to 15:1 gradient elute) to obtain trans-2-(2,5-difluorophenyl)5-methylene-3-nitrotetrahydrofuran-2H-pyran 5.5 g and cis-2-(2,5-difluorophenyl)-5-methylene-3-nitrotetrahydrofuran-2H-pyran 2.4 g. The product with the cis configuration was dissolved in 50 mL tetrahydrofuran, 120 microlitre DBU was added. Stirred for 0.5 h under room temperature then subjected to column chromatography (petroleum ether:diethyl ether=16:1 to 15:1 elute) to obtain 1.6 g trans product. A part of trans product (1 g) was separated by HPLC (ChiralCel OD) to obtain enantiomer (2R, 3S)-5-methylene-3-nitro-2-(2,4,5-trifluorophenyl)tetrahydro-2H-pyran 440 mg. .sup.1H NMR (400 MHz, CDCl.sub.3) δ7.17-7.13 (m, 1H), 7.06-7.03 (m, 2H), 5.14-5.11 (m, 2H), 5.08 (d, J=9.6 Hz, 1H), 4.82-4.73 (m, 1H), 4.39 (d, J=12.7 Hz, 1H), 4.24 (d, J=12.8 Hz, 1H), 3.13 (d, J=7.9 Hz, 2H).

Step 6. Preparation of (2R, 3S)-2-(2,5-difluorophenyl)-5-methylenetetrahydro-2H-pyran-3-amino

[0092] ##STR00025##

[0093] The product (440 mg, 2.2 mmol) obtained from the last step was dissolved in ethanol, zinc powder (1.2 g, 18.9 mmol) was added, 6N hydrochloric acid (6 mL, 36 mmol) was added under vigorous stirring. After 3 h, the pH was adjusted to 10 with 2N sodium hydroxide, extracted with diethyl ether for three times, dried over anhydrous sodium sulfate, evaporating diethyl ether under vacuum to obtain colorless and clear oily liquid 376 mg, then the next reaction was carried out directly.

Step 7. Preparation of [(2R, 3S)-5-methylene-2-(2,5-difluorophenyl)tetrahydro-2H-pyran-3-yl]tert-butyl carbamate

[0094] ##STR00026##

[0095] The colorless and clear oily liquid obtained from the last step was dissolved in dichloromethane, di-tert-butyl dicarbonate ester (507 mg, 2.34 mmol) was added, stirred at room temperature overnight, evaporating dichlormethane under vacuum to obtain 464 mg product, then the reaction of next step was carried out directly.

Step 8. Preparation of [(2R, 3S)-5-hydroxy-5-(hydroxy methyl)-2-(2,5-difluorophenyl)tetrahydro-2H-pyran-3-yl]tert-butyl carbamate

[0096] ##STR00027##

[0097] The product obtained from step 7 was dissolved in 7 mL acetone, 3.5 mL water and 14 mL tertiary butanol were added, then 0.258 mL 2.5% tertiary butanol solution of osmium tetroxide was added. Stirred at room temperature for 10 minutes, then 0.184 mL NMO was added, reacted at room temperature for 48 h, saturated sodium thiosulfate solution was added, stirred for half an hour, then extracted with ethyl acetate, dried over anhydrous sodium sulfate, concentrated to dry under vacuum to obtain 510 mg product, then the reaction of the next step was carried out directly.

Step 9. Preparation of [(2R, 3S)-5-oxo-2-(2,5-difluorophenyl)tetrahydro-2H-pyran-3-yl]tert-butyl carbamate

[0098] ##STR00028##

[0099] The product of the last step was dissolved in 10 mL tetrahydrofuran, 4 mL water solution of sodium periodate (327 mg, 1.53 mmol) was added, the mixture was stirred for 4 h and was subjected to column chromatography (10% to 20% ethyl acetate in chloroform) after concentration to obtain 410 mg white solid. .sup.1H NMR (400 MHz, CDCl.sub.3) δ 7.23 (d, J=3.3 Hz, 1H), 7.05-7.00 (m, 2H), 4.83 (d, J=8.0 Hz, 1H), 4.71 (d, J=9.0 Hz, 1H), 4.31 (dd, J=16.3, 1.5 Hz, 1H), 4.18-3.99 (m, 2H), 3.06 (dd, J=16.6, 5.1 Hz, 1H), 2.75-2.68 (m, 1H), 1.31 (s, 9H); ESI-MS: 272.1 (M+1-56).

B Preparation of Intermediate

[0100] ##STR00029##

Step 1. Preparation of

[0101] ##STR00030##

[0102] 3-oxopyrrolidine-1-tert-butyl carboxylate (40 g, 216 mmol) was dissolved in 300 mL DMF-DMA, heated for 40 minutes at 105° C. Cooled and concentrated to dry under vacuum, treated with hexane, filtered to obtain orange solid 41 g, dried, the product can be used in the reaction of the next step without purification.

Step 2. Preparation of

[0103] ##STR00031##

[0104] 41 g orange solid obtained from the last step was dissolved in 200 mL methylbenzene, 15 mL hydrazine hydrate (80% concentration) was added slowly drop by drop at 40° C., reacted for 2 h at room temperature after addition, the reaction solution was cooled with white solid separated out, the solid obtained via filtration was washed with n-heptane to obtain 37.2 g product.

Step 3. Preparation of

[0105] ##STR00032##

[0106] 37.2 g white solid obtained from the last step was dissolved in methanol, 5N hydrochloric acid was added, stirred at room temperature for 6 h, ammonia methanol solution (2N) was added after concentration, the pH was adjusted to a slightly alkaline state, 200 mL dichloromethane was added, 40 mL triethylamine was added, dichloromethane solution (40 mL) of 64 g di-tert-butyl dicarbonate was added drop by drop at room temperature, after the reaction was carried out for half an hour, the solution was concentrated to dry under vacuum, then subjected to column chromatography (methanol:aqueous ammonia:ethyl acetate=135:15:350) to obtain 20 g white solid. .sup.1H NMR (400 MHz, CDCl.sub.3) δ 8.03 (brs, 1H), 7.34 (d, J=12.8 Hz, 1H), 4.50 (t, J=16.6 Hz, 4H), 1.53 (s, 9H).

C Preparation of Intermediate

[0107] ##STR00033##

Step 1. Preparation of

[0108] ##STR00034##

[0109] N-Boc pyrazolopyrolidine (100 mg, 0.478 mmol) was dissolved in 3 mL anhydrous tetrahydrofuran, sodium hydride (30 mg, 0.718 mmol, 60% dispersion in oil) was added and stirred at room temperature for 1 h, then morpholinesulfonyl chloride (133.23 mg, 0.718 mmol) was added, reacted overnight, the solution was concentrated to dry under vacuum, water and ethyl acetate was added, after the organic layer was dried then was subjected to column chromatograph (petroleum ether: ethyl acetate=1:1) to obtain 147 mg oily liquid. .sup.1H NMR (400 MHz, CDCl.sub.3) δ 7.67 (d, J=15.4 Hz, 1H), 4.49-4.39 (m, 4H), 3.73-3.66 (m, 4H), 3.34-3.21 (m, 4H), 1.47 (s, 9H).

Step 2. Preparation of

[0110] ##STR00035##

[0111] 4 mL dichloromethane and 1 mL trifluoroacetic acid were added to the product of the last step, after 2 h of reaction at room temperature, concentrated to dry under vacuum to obtain 80 mg product, the reaction of the next step can be carried out directly without purification.

D. Preparation of compound 1: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(morpholine sulfonyl)-2,6,-dihydropyrrolo[3,4-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0112] ##STR00036##

[0113] At room temperature, the intermediates [(2R, 3S)-5-oxo-2-(2,5-difluorophenyl)tetrahydro-2H-pyran-3-yl]tert-butyl carbamate (101 mg, 0.31 mmol) and 2-(N-sulfonyl morpholine)-2,4,5,6,-tetrahydropyrrolo[3,4-c]pyrazol (80 mg, 0.31 mmol) were dissolved in 6 mL anhydrous methanol, 11.4 mg decaborane was added at room temperature, stirred overnight, concentrated to dry under vacuum, then 4 mL dichloromethane, 1 mL trifluoroacetic acid were added, stirred at room temperature for 2 h, concentrated and subjected to column chromatography (methanol:dichloromethane=1:20) to obtain 101 mg white solid. .sup.1H NMR (400 MHz, MeOD) δ 7.87 (s, 1H), 7.30-7.05 (m, 3H), 4.37-4.27 (m, 2H), 4.00-3.86 (m, 4H), 3.76-3.64 (m, 4H), 3.43 (t, J=10.7 Hz, 1H), 3.31-3.23 (m, 4H), 3.13-3.04 (m, 1H), 2.99-2.91 (m, 1H), 2.54-2.46 (m, 1H), 1.54 (q, J=11.7 Hz, 1H); ESI-HRMS: calcd for C.sub.20H.sub.26F.sub.2N.sub.5O.sub.4S, 470.1674. found, 470.1667.

Example 2

[0114] ##STR00037##

Preparation of compound 2: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(piperidine sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0115] The synthetic method of compound 2 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by piperidine sulfonyl chloride, to obtain a white solid. .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 7.89 (s, 1H), 7.21 (m, 3H), 4.16 (d, J=9.6 Hz, 1H), 4.12-4.11 (m, 1H), 3.76 (d, J=15.2 Hz, 4H), 3.26 (t, J=10.6 Hz, 1H), 3.17-3.14 (m, 4H), 2.95-2.86 (m, 2H), 2.34-2.31 (m, 1H), 1.50-1.37 (m, 7H). ESI-MS: 468.3 (M+1).

Example 3

Preparation of compound 3: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(pyrrole sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0116] ##STR00038##

[0117] The synthetic method of compound 3 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by pyrrole sulfonyl chloride, to obtain a faint yellow solid. .sup.1H NMR (400 MHz, DMSO-d.sub.6) δ 8.28 (s, 2H), 8.10 (s, 1H), 7.37-7.31 (m, 3H), 4.59 (d, J=10.0 Hz, 1H), 4.42-4.26 (m, 5H), 3.54-3.52 (m, 3H), 3.35 (t, J=6.4 Hz, 4H), 2.67-2.64 (m, 1H), 1.89 (dd, J=23.4, 11.6 Hz, 1H), 1.76-1.73 (m, 4H). ESI-MS: 454.7 (M+1).

Example 4

Preparation of compound 4: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(N-methylpiperazine sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0118] ##STR00039##

[0119] The synthetic method of compound 4 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by N-methylpiperazine sulfonyl chloride, to obtain a white solid. .sup.1H NMR (400 MHz, MeOD) δ 7.86 (s, 1H), 7.25-7.14 (m, 3H), 4.37 (d, J=9.4 Hz, 1H), 4.31-4.29 (m, 1H), 3.92-3.90 (m, 4H), 3.44 (t, J=10.5 Hz, 1H), 3.33 (br s, 4H), 3.12-3.20 (m, 2H), 2.50 (br s, 5H), 2.30 (s, 3H), 1.58 (dd, J=23.2, 11.7 Hz, 1H). ESI-MS: 483.1 (M+1).

Example 5

Preparation of compound 5: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(4-cyclopentylpiperazine-1-yl-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0120] ##STR00040##

[0121] The synthetic method of compound 5 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by 4-cyclopentylpiperazine-1-yl-sulfonyl chloride, to obtain a white solid. .sup.1H NMR (400 MHz, MeOD) δ 7.86 (s, 1H), 7.26-7.10 (m, 3H), 4.33 (d, J=9.6 Hz, 1H), 4.30-4.28 (m, 1H), 3.91-3.90 (m, 4H), 3.43 (t, J=10.7 Hz, 1H), 3.33 (br s, 4H), 3.10-3.04 (m, 1H), 3.01-2.95 (m, 1H), 2.58-2.49 (m, 6H), 1.92-1.87 (m, 2H), 1.74-1.70 (m, 2H), 1.62-1.50 (m, 3H), 1.41-1.31 (m, 2H). ESI-MS: 537.4 (M+1).

Example 6

Preparation of compound 6: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(3-oxopiperazine-1-yl-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0122] ##STR00041##

[0123] The synthetic method of compound 6 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by 3-oxopiperazine-1-yl-sulfonyl chloride, to obtain a white solid. ESI-MS: 483.1 (M+1).

Example 7

Preparation of compound 7: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(3-hydroxyazetidine-1-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0124] ##STR00042##

[0125] The synthetic method of compound 7 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by 3-hydroxyazetidine-1-sulfonyl chloride, to obtain a white solid. ESI-MS: 456.1 (M+1).

Example 8

Preparation of compound 8: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(1-isopropylpiperidine-4-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0126] ##STR00043##

[0127] The synthetic method of compound 8 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by 1-isopropylpiperidine-4-sulfonyl chloride, to obtain a faint yellow solid. ESI-MS: 510.2 (M+1).

Example 9

Preparation of compound 9: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(4-(methylsulfonyl) piperazine-1-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0128] ##STR00044##

[0129] The synthetic method of compound 9 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by 4-(methylsulfonyl) piperazine-1-sulfonyl chloride, to obtain a white solid. ESI-MS: 547.5 (M+1).

Example 10

Preparation of compound 10: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-N-ethyl-5-[2-(morpholine sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0130] ##STR00045##

[0131] Compound 10 of the present invention was obtained through the reaction of compound 1 with bromoethane under basic condition, it is a light yellow solid. ESI-MS: 498.5 (M+1).

Example 11

Preparation of compound 11: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-N,N-diisopropyl-5-[2-(morpholine sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]-tetrahydro-2H-pyran-3-amine

[0132] ##STR00046##

[0133] Compound 11 of the present invention was obtained through the reaction of compound 1 with isopropyl bromide under basic condition, it is a grey solid. ESI-MS: 554.3 (M+1).

Example 12

Preparation of compound 12: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-N,N-dibutyl-5-[2-(morpholine sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0134] ##STR00047##

[0135] Compound 12 of the present invention was obtained through the reaction of compound 1 with butyl bromide under basic condition, it is a white solid. ESI-MS: 581.6 (M+1).

Example 13

Preparation of compound 13: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(azetidine-1-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0136] ##STR00048##

[0137] The synthetic method of compound 13 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by azetidine-1-sulfonyl chloride, to obtain a white solid. .sup.1H NMR (400 MHz, MeOD) δ 7.82 (s, 1H), 7.23-7.04 (m, 3H), 4.34-4.28 (m, 2H), 4.06 (t, J=7.8 Hz, 4H), 3.96-3.92 (m, 4H), 3.46 (t, J=10.7 Hz, 1H), 3.15-3.07 (m, 1H), 3.01-2.94 (m, 1H), 2.53-2.49 (m, 1H), 2.23-2.15 (m, 2H), 1.56 (q, J=11.7 Hz, 1H). ESI-MS: 440.4 (M+1).

Example 14

Preparation of compound 14: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(4-methyl piperazine-1-sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0138] ##STR00049##

[0139] The synthetic method of compound 14 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by 4-methyl piperazine-1-sulfonyl chloride, to obtain a white solid. .sup.1H NMR (400 MHz, MeOD) δ 7.89 (s, 1H), 7.26-7.17 (m, 3H), 4.16-4.11 (m, 2H), 3.76 (d, J=14.5 Hz, 4H), 3.70-3.67 (m, 2H), 3.26 (t, J=10.6 Hz, 1H), 2.94-2.83 (m, 2H), 2.66 (t, J=11.7 Hz, 2H), 2.34-2.31 (m, 1H), 1.65-1.62 (m, 2H), 1.45-1.36 (m, 2H), 1.11-1.01 (m, 2H), 0.84 (d, J=6.5 Hz, 3H). ESI-MS: 482.1 (M+1).

Example 15

Preparation of compound 15: (2R, 3S, 5R)-2-(2,5-difluorophenyl)-5-[2-(perhydroindole-1 sulfonyl)-2,6-dihydropyrrolo[3,4,-c]pyrazol-5(4H)-yl]tetrahydro-2H-pyran-3-amine

[0140] ##STR00050##

[0141] The synthetic method of compound 15 of the present invention refers to example 1, the morpholinesulfonyl chloride in example 1 was replaced by perhydroindole-1-sulfonyl chloride, to obtain a white solid. .sup.1H NMR (400 MHz, MeOD) δ 7.92 (s, 1H), 7.27-7.18 (m, 3H), 4.20 (d, J=9.6 Hz, 1H), 4.15-4.12 (m, 1H), 3.76 (d, J=12.1 Hz, 4H), 3.40-3.36 (m, 3H), 3.27 (t, J=10.8 Hz, 2H), 3.22-3.18 (m, 3H), 2.99-2.90 (m, 2H), 2.36-2.33 (m, 1H), 2.15-2.12 (m, 2H), 1.45-1.35 (m, 6H). ESI-MS: 508.2 (M+1)

Biological Evaluation

Test 1

[0142] Test of the inhibition activity of the compound of the present invention to the DPP-4 enzyme:

[0143] Suitable amount of DPP-4 enzyme (SIGMA), HEPES buffer solution from a sample box that was subjected to three times gradient dilution were added in the reaction system, blank control (which does not contain enzyme and sample box), negative control (which does not contain sample) and positive control (positive control is MK-3102) were provided simultaneously, the reaction was carried out at room temperature for 10 minutes, then the substrate Gly-Pro-7-amido-4-methylcoumarin (SIGMA) was added, the reaction was carried out for 30 minutes at room temperature and avoid light, fluorescence was tested, excitation wavelength was 355 nm, emission wavelength was 460 nm.

[0144] Inhibition ratio was calculated according to the measurements of fluorescence, inhibition ratio=[1−(sample-blank)/(negative-blank)]*100%, IC.sub.50 value was calculated by 4ParameteriLogistic Model of Xlfit software. The experiment results are shown in table 1.

TABLE-US-00001 TABLE 1 Test results of activities of the compounds of the examples and the comparative compounds such as Sitagliptin etc to DPP-4 in vitro. Compound DPP-4 inhibition Drugs on the market or DPP-4 inhibition No. ID.sub.50 (nM) compounds from documents IC.sub.50 (nM) 1 0.5 Sitagliptin 15 2 0.8 Vildagliptin 2.8 3 0.3 [00051] 1.6 4 0.6 MK-3102 2.2 5 0.2 [00052] 1.8 13 0.5 [00053] 1.4 14 0.4 15 0.7

[0145] Conclusion: the compounds of the present invention have significant inhibition effect to DPP-4 enzyme.

[0146] In another aspect, in the stability test of human liver microsomes, compared with MK-3102, the compounds 1, 4 of the present invention and so on have better metabolism stability, indicating that the compounds of the present invention have the prospect of becoming long-term antidiabetic medicine.