C-3 novel triterpenone with C-28 urea derivatives as HIV inhibitors

Abstract

The present invention relates to C-3 novel triterpenone with C-28 urea derivatives of formula (I); or pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable hydrates, tautomers, stereoisomers, prodrugs, compositions or combination thereof, wherein R.sub.1, R.sub.2, R.sub.3, W, J and X are as defined herein. The present invention also relates to pharmaceutical compositions comprising compounds of formula (I) useful for the treatment of viral diseases and particularly HIV mediated diseases. ##STR00001##

Claims

1. The compound of the formula (I): ##STR00096## wherein, R.sub.1 is ##STR00097## ##STR00098## (wherein R.sub.e is hydrogen, substituted or unsubstituted alkyl, or substituted or unsubstituted cycloalkyl); R.sub.2 is hydrogen or substituted or unsubstituted alkyl; R.sub.3 is hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted amino alkyl, substituted or unsubstituted alkoxylalkoxy, substituted or unsubstituted alkoxylalkyl, substituted or unsubstituted arylalkyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted heterocyclylalkyl or substituted or unsubstituted heteroarylalkyl; wherein the substituents are alkyl, halo or hydroxyl; W is (CR.sub.aR.sub.b).sub.n; R.sub.a and R.sub.b are independently hydrogen or substituted or unsubstituted alkyl, or R.sub.a and R.sub.b are taken together with the carbon to which they are attached to form 3-6 membered cycloalkyl; W and R.sub.3 are taken together with the nitrogen to which they are attached to form substituted or unsubstituted 4-10 membered heterocyclyl; wherein the substituents are alkyl, halo or hydroxyl; J is absent, (CR.sub.cR.sub.d).sub.1-2 or NR.sub.g; R.sub.c and R.sub.d are independently hydrogen or R.sub.c and R.sub.d are taken together with the carbon to which they are attached to form 3-6 membered cycloalkyl; R.sub.g is hydrogen or substituted or unsubstituted alkyl; R.sub.3 and R.sub.g are taken together with the nitrogen atoms to which they are attached to form substituted or unsubstituted 4-10 membered heterocyclyl; wherein the substituents are alkyl, halo or hydroxyl; X is absent, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl or substituted or unsubstituted heteroaryl; wherein the substituent is one or more R.sub.f; R.sub.f is independently halogen, hydroxyl, alkyl, alkoxy, aryl, O-heterocyclyl, O-aminoalkyl or aminoalkyl; and n is 1 to 4; or pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable hydrates, tautomers, stereoisomers, ester prodrugs, or combination thereof.

2. The compound according to claim 1, is a compound of the formula (IA): ##STR00099## wherein, R.sub.1, R.sub.2, R.sub.3, R.sub.a, R.sub.b, J, X and n are same as defined in claim 1; or pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable hydrates, tautomers, stereoisomers, prodrugs, or combination thereof.

3. The compound according to claim 1, is a compound of the formula (IB): ##STR00100## wherein, R.sub.1, R.sub.2, J and X are same as defined in claim 1 and ##STR00101## is substituted or unsubstituted 4-7 membered heterocyclyl; or pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable hydrates, tautomers, stereoisomers, prodrugs, or combination thereof.

4. The compound of formula ##STR00102## wherein, R2 is hydrogen or substituted or unsubstituted alkyl; R3 is hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted amino alkyl, substituted or unsubstituted alkoxylalkoxy, substituted or unsubstituted alkoxylalkyl, substituted or unsubstituted arylalkyl, substituted or unsubstituted cycloalkylalkyl, substituted or unsubstituted heterocyclylalkyl or substituted or unsubstituted heteroarylalkyl; wherein the substituents are alkyl, halo or hydroxyl; W is (CRaRb).sub.n; R.sub.a and R.sub.b are independently hydrogen or substituted or unsubstituted alkyl, or R.sub.a and R.sub.b are taken together with the carbon to which they are attached to form 3-6 membered cycloalkyl; W and R.sub.3 are taken together with the nitrogen to which they are attached to form substituted or unsubstituted 4-10 membered heterocyclyl; wherein the substituents are alkyl, halo or hydroxyl; J is absent, (CR.sub.cR.sub.d).sub.1-2 or NR.sub.g; R.sub.c and R.sub.d are independently hydrogen or R.sub.c and R.sub.d are taken together with the carbon to which they are attached to form 3-6 membered cycloalkyl; R.sub.g is hydrogen or substituted or unsubstituted alkyl; R.sub.3 and R.sub.g are taken together with the nitrogen atoms to which they are attached to form substituted or unsubstituted 4-10 membered heterocyclyl; wherein the substituents are alkyl, halo or hydroxyl; X is absent, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heterocyclyl or substituted or unsubstituted heteroaryl; wherein the substituent is one or more R.sub.f; R.sub.f is independently halogen, hydroxyl, alkyl, alkoxy, aryl, O-heterocyclyl, O-aminoalkyl or aminoalkyl; and n is 1 to 4; or pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable hydrates, tautomers, stereoisomers, ester prodrugs, or combination thereof.

5. The compound according to claim 1, wherein R.sub.2 is hydrogen.

6. The compound according to claim 1, wherein J is absent or NR.sub.g.

7. The compound according to claim 1, wherein R.sub.3 is hydrogen, substituted or unsubstituted alkyl, substituted or unsubstituted amino alkyl, or substituted or unsubstituted heterocyclylalkyl; wherein the substituents are alkyl, halo or hydroxyl.

8. A compound selected from the group consisting of: (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid hydrochloride, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(dimethyl amino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(1-(4-chlorophenyl) cyclopropyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(2-(4-chlorophenyl) propan-2-yl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-((1-(4-chlorophenyl) cyclopropyl)methyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-penta methyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclo penta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-((1R,3S,5S)-3-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)-8-azabicyclo[3.2.1]octane-8-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadeca hydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(pyrrolidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-(3-(2-(5-phenyl-1H-imidazol-2-yl)propan-2-yl)ureido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(piperidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid hydrochloride, (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-(4-(2-(3-iso propyl-5-methyl-4H-1,2,4-triazol-4-yl)ethyl)piperazine-1-carboxamido)-5a,5b,8,8,11a-penta methyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a, 8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclo penta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, and (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(pyrrolidin-1-ylmethyl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid, or pharmaceutically acceptable salts, pharmaceutically acceptable solvates, pharmaceutically acceptable hydrates, tautomers, stereoisomers, ester prodrugs, or combination thereof.

9. A pharmaceutical composition comprising a compound according to claim 1 and at least one pharmaceutically acceptable excipient.

10. The pharmaceutical composition according to claim 9, wherein the pharmaceutically acceptable excipient is a carrier or diluent.

11. A pharmaceutical composition comprising a compound according to claim 8 and at least one pharmaceutically acceptable excipient.

Description

EXAMPLES

Example 1: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid hydrochloride

(1) ##STR00063##

Step 1: Synthesis of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate

(2) ##STR00064##

(3) To a stirred solution of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate (Intermediate-1 11.0 g, 21.61 mmol, 1.0 eq) in THF (160 ml) at 0 C. was added DIPEA (11.15 g, 86.44 mmol, 4.0 eq) and N-(4-chlorobenzyl)-N.sup.2,N.sup.2-dimethylethane-1,2-diamine (Intermediate-3 9.16 g, 43.22 mmol, 2.0 eq). The reaction mixture was allowed to stir at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with water (100 ml) and extracted with DCM (3200 ml). The combined organic extracts were washed with water (100 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% MeOH:DCM as an eluent to obtain the desired product (11.0 g, 70% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 8.28 (s, 1H), 7.28 (d, J=8.1 Hz, 2H), 7.17 (d, J=8.1 Hz, 2H), 4.53-4.34 (m, 3H), 3.35-3.25 (m, 1H), 3.20-2.98 (m, 3H), 2.69 (d, J=18.6 Hz, 1H), 2.63-2.56 (m, 1H), 2.40 (d, J=18.9 Hz, 1H), 2.33-2.27 (m, 2H), 2.17 (s, 6H), 2.05 (s, 3H), 2.02-1.57 (m, 8H), 1.51-1.20 (m, 13H), 1.13 (s, 3H), 1.09-1.01 (m, 1H), 0.95 (s, 3H), 0.92 (s, 3H), 0.86 (s, 3H), 0.85 (s, 3H), 0.81 (m, 1H); ESI-MS: m/z 744.54 (M+Na).sup.+.

Step 2: Synthesis of 1-(4-chlorobenzyl)-1-(2-(dimethylamino)ethyl)-3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a, 5b,8,8,11a-pentamethyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-3aH-cyclopenta[a]chrysen-3a-yl)urea

(4) ##STR00065##

(5) To a stirred solution of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate (step 1, 11.0 g, 15.22 mmol, 1.0 eq) in THF (60 ml), MeOH (120 ml) and water (30 ml) at 0 C. was added NaOH (9.135 g, 228.38 mmol, 15.0 eq). The reaction mixture was allowed to stir at room temperature for about 6 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with water (100 ml) and extracted with DCM (3200 ml). The combined organic extracts were washed with water (100 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% MeOH:DCM as an eluent to obtain the desired product (9.53 g, 92% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 8.29 (s, 1H), 7.28 (d, J=8.4 Hz, 2H), 7.17 (d, J=8.4 Hz, 2H), 4.50, 4.38 (ABq, J.sub.AB=15.5 Hz, 2H), 3.36-2.97 (m, 5H), 2.70 (d, J=18.9 Hz, 1H), 2.64-2.54 (m, 1H), 2.40 (d, J=18.6 Hz, 1H), 2.33-2.27 (m, 2H), 2.17 (s, 6H), 2.05-1.85 (m, 3H), 1.80-1.72 (m, 1H), 1.71-1.64 (m, 2H), 1.56-1.28 (m, 8H), 1.27-1.18 (m, 7H), 1.13 (s, 3H), 1.08-1.02 (m, 1H), 0.98 (s, 3H), 0.95 (s, 3H), 0.90 (s, 3H), 0.77 (s, 3H), 0.75-0.70 (m, 1H); ESI-MS: m/z 702.5 (M+Na).sup.+.

Step 3: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a, 5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(6) ##STR00066##

(7) To a stirred solution of 1-(4-chlorobenzyl)-1-(2-(dimethylamino)ethyl)-3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-3aH-cyclopenta[a]chrysen-3a-yl) urea (step 2, 4.0 g, 5.891 mmol, 1.0 eq) and (1S,3R)-3-((benzyloxy)carbonyl)-2,2-dimethyl cyclobutane-1-carboxylicacid (prepared as described in WO/2011/007230 A2, 2.3 g, 8.836 mmol, 1.5 eq) in DCM (150 ml) at 0 C. was added triethyl amine (2.97 g, 29.455 mmol, 5.0 eq), DMAP (0.359 g, 2.945 mmol, 0.5 eq) and 2,4,6-trichlorobenzoyl chloride (2.874 g, 11.782 mmol, 2.0 eq). The reaction mixture was flushed with nitrogen and allowed to stir at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (200 ml) and extracted with DCM (3200 ml). The combined organic extracts were dried over Na.sub.2SO.sub.4, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 4% MeOH:DCM as an eluent to obtain the desired product (4.5 g, 83.3% yield) as a white solid.

Step 4: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(8) ##STR00067##

(9) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 3, 4.5 g, 4.87 mmol, 1.0 eq) in MeOH (60 ml), THF (45 ml) and water (45 ml) was added KOH (1.911 g, 34.12 mmol, 7.0 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with water (10 ml) and pH adjusted to 6.0 with 1N HCl and extracted with DCM (3200 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 8% MeOH:DCM as an eluent to obtain the desired product (3.5 g, 87.5% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.27 (br.s., 1H), 7.45 (d, J=8.1 Hz, 2H), 7.12 (d, J=7.2 Hz, 2H), 4.54 (m, 2H), 4.38-4.31 (m, 1H), 3.10-2.95 (m, 1H), 2.85-2.72 (m, 5H), 2.40-2.22 (m, 6H), 2.13 (s, 6H), 1.95-1.52 (m, 13H), 1.50-1.22 (m, 12H), 1.20-0.9 (m, 8H), 0.90-0.70 (m, 13H); ESI-MS: m/z 834.56 (M+H).sup.+.

Step 5: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid hydrochloride

(10) To a stirred solution of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid (step 4, 2.0 g, 2.40 mmol, 1.0 eq) in 1,4-dioxane (10 ml) at 0 C. was added 1.5N HCl/1,4-dioxane (40 ml). After stirring at room temperature for overnight, the reaction mixture was evaporated to dryness. The residue was triturated with n-hexane and the solids that formed were collected by filtration were taken into MTBE (20 ml) and heated to reflux for about 20 minutes. The mixture was cooled to 0 C., filtered and dried under vacuum to obtain the desired product (1.6 g, 77% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.15 (br.s., 1H), 10.20 (br.s., 1H), 7.43 (d, J=8.4 Hz, 2H), 7.21 (d, J=8.4 Hz, 2H), 6.33 (s, 1H), 4.68, 4.52 (ABq, J.sub.AB=17.4 Hz, 2H), 4.38-4.31 (m, 1H), 3.78-3.65 (m, 1H), 3.55-3.40 (m, 2H), 3.21-3.13 (m, 3H), 2.83-2.60 (m, 4H), 2.75 (s, 6H), 2.37-2.25 (m, 1H), 2.10 (d, J=18.3 Hz, 1H), 1.93-1.80 (m, 2H), 1.80-1.38 (m, 7H), 1.38-1.20 (m, 8H), 1.17-0.97 (m, 10H), 0.91 (s, 3H), 0.86 (s, 3H), 0.84 (s, 3H), 0.80 (s, 6H), 0.64 (s, 3H); ESI-MS: m/z 834.63 (M-HCl+H).sup.+; HPLC: 93.62%.

Example 2: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(dimethylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(11) ##STR00068##

Step 1: Synthesis of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(dimethyl amino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate

(12) ##STR00069##

(13) To a stirred solution of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate (Intermediate-1, 2.0 g, 3.929 mmol, 1.0 eq) in THF (20 ml) was added DIPEA (2.8 ml, 15.717 mmol, 4.0 eq) and (S)N,N-dimethyl-2-(5-phenyl-2-(pyrrolidin-2-yl)-1H-imidazol-1-yl)ethan-1-amine (prepared as described in: WO 2016/001820 A1, 2.2 g, 7.85 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with ethyl acetate (200 ml) and washed with water (2100 ml). The organic layer was dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-3% MeOH in DCM gradient to obtain the desired product (2.0 g, 64% yield) as a white solid; ESI-MS: m/z 816.6 (M+Na).sup.+.

Step 2: Synthesis of (S)-2-(1-(2-(dimethylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)-N-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a, 5b,8,8,11a-pentamethyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-3aH-cyclopenta[a]chrysen-3a-yl)pyrrolidine-1-carboxamide

(14) ##STR00070##

(15) To a stirred solution of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(dimethylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadeca hydro-2H-cyclopenta[a]chrysen-9-yl acetate (step 1, 2.0 g, 2.52 mmol, 1.0 eq) in MeOH (88 ml), THF (44 ml) and water (22 ml) at 0 C. was added NaOH (1.0 g, 25.2 mmol, 10.0 eq). The reaction mixture was allowed to stir at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with DCM (100 ml) and was washed with water (2100 ml). The organic layer was dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-4% MeOH in DCM gradient to obtain the desired product (1.8 g, 95% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 7.68 (d, J=7.2 Hz, 2H), 7.52 (s, 1H), 7.35-7.25 (m, 2H), 7.20-7.10 (m, 1H), 5.82 (s, 1H), 5.10-5.0 (m, 1H), 4.20-4.03 (m, 2H), 3.70-3.60 (m, 1H), 3.50-3.38 (m, 1H), 3.10-2.92 (m, 2H), 2.88-2.78 (m, 1H), 2.70-2.60 (m, 2H), 2.43-2.40 (m, 1H), 2.30-2.10 (m, 9H), 2.09-1.75 (m, 6H), 1.70-1.55 (m, 2H), 1.55-1.40 (m, 3H), 1.40-1.20 (m, 6H), 1.20-1.10 (m, 7H), 1.0-0.90 (m, 4H), 0.87 (s, 3H), 0.83 (s, 3H), 0.75 (s, 3H), 0.65 (m, 4H); ESI-MS: m/z 774.41 (M+Na).sup.+.

Step 3: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(di methylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11a,11b,12,13,13a-octadeca hydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(16) ##STR00071##

(17) To a stirred solution of (S)-2-(1-(2-(dimethylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)-N-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-penta methyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-3aH-cyclo penta[a]chrysen-3a-yl)pyrrolidine-1-carboxamide (step 2, 1.8 g, 2.4 mmol, 1.0 eq) and (1S,3R)-3-((benzyloxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid (prepared as described in WO/2011/007230 A2, 0.94 g, 3.6 mmol, 1.5 eq) in DCM (20 ml) at 0 C. were added triethylamine (1.7 ml, 12.0 mmol, 5.0 eq), DMAP (0.146 g, 1.2 mmol, 0.5 eq) and 2,4,6-trichlorobenzoyl chloride (0.58 ml, 3.6 mmol, 1.5 eq). The reaction mixture was allowed to stir at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with DCM (100 ml) and was washed with water (2100 ml). The organic layer was dried over Na.sub.2SO.sub.4, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-3% MeOH in DCM gradient to obtain the desired product (2.0 g, 84% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.40-7.20 (m, 11H), 5.20-5.08 (m, 2H), 5.08-5.0 (m, 1H), 4.50-4.40 (m, 1H), 4.18-4.05 (m, 2H), 3.92-3.78 (m, 1H), 3.55-3.45 (m, 1H), 3.02-2.40 (m, 11H), 2.34 (s, 6H), 2.18-2.05 (m, 4H), 1.80-1.40 (m, 12H), 1.40-1.30 (m, 6H), 1.30-1.20 (m, 6H), 1.20-1.10 (m, 3H), 1.10-0.92 (m, 7H), 0.91 (s, 3H), 0.88-0.80 (m, 6H), 0.80-0.72 (m, 1H).

Step 4: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(di methylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadeca hydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(18) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-((S)-2-(1-(2-(dimethylamino)ethyl)-5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 3, 2.0 g, 2.0 mmol, 1.0 eq) in MeOH (38 ml) and THF (38 ml) was added aqueous 2.5N KOH solution (6.4 ml, 15.09 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, cooled to 0 C., acidified with 1N HCl to pH-6 and was extracted with DCM (100 ml). The organic layer was washed with water (2100 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-7% MeOH in DCM gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to give the desired product (50 mg, 3% yield) as an off-white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.17 (br.s., 1H), 7.68 (d, J=7.2 Hz, 2H), 7.53 (s, 1H), 7.35-7.27 (m, 2H), 7.19-7.14 (m, 1H), 5.86 (m, 1H), 5.09 (m, 1H), 4.49-4.30 (m, 1H), 4.25-4.08 (m, 2H), 3.70-3.60 (m, 1H), 3.12-3.0 (m, 3H), 2.87-2.70 (m, 3H), 2.70-2.10 (m, 10H), 2.0-1.80 (m, 8H), 1.75-1.42 (m, 6H), 1.40-1.30 (m, 3H), 1.30-1.18 (m, 7H), 1.17-1.03 (m, 9H), 1.01-0.89 (m, 4H), 0.89-0.75 (m, 13H); ESI-MS: m/z 906.68 (M+H).sup.+; HPLC: 92.04%.

Example 3: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(19) ##STR00072##

Step 1: Synthesis of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-penta methyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate

(20) ##STR00073##

(21) To a stirred solution of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate (Intermediate-1, 2.26 g, 4.44 mmol, 1.0 eq) in THF (22 ml) was added DIPEA (2.29 g, 17.76 mmol, 4.0 eq) and (S)-5-phenyl-2-(pyrrolidin-2-yl)-1H-imidazole (prepared as described in WO 2014/105926 A1, 1.89 g, 8.88 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with water and extracted with DCM (2100 ml). The combined organic extracts were washed with brine solution, dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-5% methanol in DCM eluent to obtain the desired product (2.5 g, 78% yield) as a brown color solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 10.44 (br.s., 1H), 7.78-7.75 (m, 2H), 7.40-7.30 (m, 2H), 7.30-7.18 (m, 2H), 5.10-5.02 (m, 1H), 4.53-4.45 (m, 1H), 3.45-3.35 (m, 2H), 3.20-3.08 (m, 1H), 3.0-2.72 (m, 3H), 2.38-2.18 (m, 4H), 2.15-2.0 (m, 1H), 2.05 (s, 3H), 2.0-1.48 (m, 10H), 1.42-1.20 (m, 11H), 1.17-1.0 (m, 1H), 1.05 (s, 3H), 0.97-0.89 (m, 6H), 0.87-0.78 (m, 7H); ESI-MS: m/z 723.72 (M+H).sup.+.

Step 2: Synthesis of (S)N-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadeca hydro-3aH-cyclopenta[a]chrysen-3a-yl)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamide

(22) ##STR00074##

(23) To a stirred solution of (3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl acetate (step 1, 2.5 g, 3.462 mmol, 1.0 eq) in MeOH (66.3 ml), THF (33.8 ml) and water (16.9 ml) at 0 C. was added NaOH (1.385 g, 34.62 mmol, 10.0 eq). The reaction mixture was allowed to stir at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with DCM, washed with water and brine solution. The organic layer was dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-5% MeOH in DCM gradient to obtain the desired product (1.3 g, 56.5% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 10.36 (br.s., 1H), 7.80-7.68 (m, 2H), 7.42-7.30 (m, 2H), 7.30-7.12 (m, 2H), 5.10-5.0 (m, 1H), 3.47-3.35 (m, 2H), 3.25-3.08 (m, 2H), 2.90-2.75 (m, 3H), 2.37-2.20 (m, 3H), 2.20-2.02 (m, 2H), 2.0-1.85 (m, 3H), 1.85-1.75 (m, 3H), 1.60-1.48 (m, 3H), 1.48-1.12 (m, 12H), 1.05 (s, 3H), 1.0-0.85 (m, 1H), 1.0 (s, 3H), 0.97 (s, 3H), 0.87 (s, 3H), 0.76 (s, 3H), 0.72-0.67 (m, 1H); ESI-MS: m/z 703.5 (M+Na).sup.+.

Step 3: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(24) ##STR00075##

(25) To a stirred solution of (S)N-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-9-hydroxy-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-2,3,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-3aH-cyclopenta[a]chrysen-3a-yl)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamide (step 2, 1.3 g, 1.911 mmol, 1.0 eq) and (1S,3R)-3-((benzyloxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid (prepared as described in WO 2013/160810 A2, 0.751 g, 2.867 mmol, 1.5 eq) in DCM (13 ml) at 0 C. were added triethylamine (1.33 ml, 9.558 mmol, 5.0 eq), DMAP (0.116 g, 0.955 mmol, 0.5 eq) and 2,4,6-trichlorobenzoyl chloride (0.45 ml, 2.867 mmol, 1.5 eq). The reaction mixture was allowed to stir at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (50 ml) and extracted with DCM (350 ml). The combined organic extracts were washed with brine solution (50 ml), dried over Na.sub.2SO.sub.4, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% methanol in DCM as an eluent to obtain the desired product (0.87 g, 50.28% yield) as a brown color solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.75-7.72 (m, 2H), 7.40-7.30 (m, 7H), 7.30-7.20 (m, 2H), 5.15, 5.09 (ABq, J.sub.AB=12.3 Hz, 2H), 5.07-5.0 (m, 1H), 4.44 (dd, J=11.1, 4.5 Hz, 1H), 3.45-3.35 (m, 2H), 3.20-3.08 (m, 1H), 3.0-2.60 (m, 5H), 2.40-2.20 (m, 5H), 2.20-1.90 (m, 4H), 1.90-1.20 (m, 22H), 1.10-0.78 (m, 20H).

Step 4: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(26) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-iso propyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(5-phenyl-1H-imidazol-2-yl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclo penta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 3, 0.870 g, 0.957 mmol, 1.0 eq) in MeOH (17.4 ml) and THF (17.4 ml) was added aqueous 2.5N KOH solution (2.82 ml, 7.05 mmol, 7.5 eq). The reaction mixture was allowed to stir at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, reaction mixture was diluted with water (50 ml), cooled to 0 C., acidified with 1N HCl to pH-5 and extracted with DCM (250 ml). The combined organic extracts were washed with water (50 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% methanol in DCM as an eluent to obtain the desired product (0.23 g, 29.2% yield) as a brown color solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 12.04 (br.s., 1H), 7.72 (d, J=7.2 Hz, 2H), 7.54 (s, 1H), 7.38-7.28 (m, 2H), 7.20-7.10 (m, 1H), 6.37 (s, 1H), 4.90-4.82 (m, 1H), 4.40-4.28 (m, 1H), 3.52-3.40 (m, 2H), 3.10-2.96 (m, 1H), 2.84-2.70 (m, 3H), 2.38-2.22 (m, 3H), 2.20-2.0 (m, 4H), 2.0-1.30 (m, 12H), 1.30-1.23 (m, 4H), 1.23-1.16 (m, 3H), 1.15-0.98 (m, 8H), 0.91 (s, 3H), 0.87-0.73 (m, 16H); ESI-MS: m/z 835.56 (M+H).sup.+; HPLC: 94.9%.

Example 4: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(1-(4-chlorophenyl)cyclopropyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(27) ##STR00076##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(1-(4-chloro phenyl)cyclopropyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(28) ##STR00077##

(29) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-iso cyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 3.0 g, 4.213 mmol, 1.0 eq) in THF (30 ml) was added DIPEA (2.16 ml, 12.64 mmol, 3.0 eq) followed by 1-(4-chlorophenyl)cyclopropan-1-amine (Intermediate-4, 0.847 g, 5.056 mmol, 1.2 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (75 ml) and extracted with ethyl acetate (375 ml). The combined organic extracts were washed with water (75 ml) and brine solution (50 ml). The organic layer was dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-2% methanol in dichloromethane gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to give the desired product (3.0 g, 80.9% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.37-7.34 (m, 5H), 7.30 (d, J=8.7 Hz, 2H), 7.13 (d, J=8.7 Hz, 2H), 5.16, 5.10 (ABq, J.sub.AB=12.3 Hz, 2H), 5.09 (s, 1H), 4.76 (s, 1H), 4.44 (dd, J=11.4, 4.8 Hz, 1H), 3.18-3.07 (m, 1H), 2.87-2.57 (m, 5H), 2.20 (d, J=18.3 Hz, 1H), 2.14-1.98 (m, 2H), 1.91-1.80 (m, 2H), 1.80-1.61 (m, 4H), 1.56-1.39 (m, 4H), 1.39-1.25 (m, 6H), 1.34 (s, 3H), 1.22 (s, 3H), 1.19 (s, 3H), 1.17-1.0 (m, 4H), 0.97 (s, 3H), 0.91 (s, 3H), 0.88 (s, 3H), 0.85 (s, 6H), 0.79 (m, 1H), 0.75 (s, 3H); ESI-MS: m/z 901.46 (M+Na).sup.+.

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(1-(4-chloro phenyl)cyclopropyl)ureido)-1-isopropyl-5a, 5b,8,8,11a-pentamethyl-2-oxo-3,3a, 4,5,5a, 5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(30) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(1-(4-chlorophenyl)cyclopropyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 3.0 g, 3.41 mmol, 1.0 eq) in MeOH (60 ml) and THF (60 ml) was added aqueous 2.5N KOH solution (10.23 ml, 25.579 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure. The reaction mixture was cooled to 0 C., diluted with water (25 ml), pH adjusted to 5.0 with 1N HCl and extracted with DCM (375 ml). The combined organic extracts were washed with water (75 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-4% methanol in dichloromethane gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to obtain the solid. To this resulting solid compound, methyl-tert-butyl ether:hexane (80 ml, 1:2) was added and heated to reflux for about 30 minutes, then slowly cooled to 0 C., filtered and dried under vacuum to obtain the desired product (1.74 g, 64.63% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.29 (d, J=8.7 Hz, 2H), 7.15 (d, J=8.4 Hz, 2H), 5.63 (s, 1H), 4.97 (s, 1H), 4.48 (dd, J=11.1, 4.5 Hz, 1H), 3.18-3.07 (m, 1H), 2.87-2.68 (m, 3H), 2.68-2.53 (m, 2H), 2.20 (d, J=18.6 Hz, 1H), 2.12-2.02 (m, 2H), 1.90-1.80 (m, 2H), 1.73-1.65 (m, 4H), 1.50-1.40 (m, 3H), 1.40-1.30 (m, 5H), 1.38 (s, 3H), 1.30-1.07 (m, 10H), 1.09 (s, 3H), 1.07-0.75 (m, 15H), 0.70 (s, 3H); ESI-MS: m/z 789.4 (M+H).sup.+.

Example 5: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(2-(4-chlorophenyl)propan-2-yl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(31) ##STR00078##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(2-(4-chloro phenyl)propan-2-yl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(32) ##STR00079##

(33) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-iso cyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.40 mmol, 1.0 eq) in THF (15 ml) was added DIPEA (0.72 g, 5.62 mmol, 4.0 eq) and 2-(4-chlorophenyl)propan-2-amine (Intermediate-5, 0.35 g, 2.1 mmol, 1.5 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (50 ml) and extracted with ethyl acetate (360 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 50% ethyl acetate:hexane as an eluent to obtain the desired product (0.804 g, 65.0% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.40-7.30 (m, 9H), 5.15, 5.10 (ABq, J.sub.AB=12.3 Hz, 2H), 4.65 (s, 1H), 4.44 (dd, J=11.1, 4.8 Hz, 1H), 4.04 (s, 1H), 3.15-3.05 (m, 1H), 2.86-2.54 (m, 5H), 2.252 (d, J=18.9 Hz, 1H), 2.18-2.10 (m, 1H), 2.09-2.0 (m, 1H), 1.95-1.82 (m, 1H), 1.80-1.65 (m, 4H), 1.60 (s, 3H), 1.55 (s, 3H), 1.54-1.50 (m, 1H), 1.49-1.30 (m, 5H), 1.34 (s, 3H), 1.30-1.10 (m, 10H), 1.08-1.03 (m, 1H), 1.05 (s, 3H), 0.96 (s, 3H), 0.95 (s, 3H), 0.89-0.83 (m, 9H), 0.81-0.78 (m, 1H); ESI MS: m/z 903.6 (M+Na).sup.+.

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(2-(4-chloro phenyl)propan-2-yl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy) carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(34) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(2-(4-chlorophenyl)propan-2-yl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.800 g, 0.908 mmol, 1.0 eq) in MeOH (20 ml) and THF (20 ml) was added aqueous 2.5N KOH solution (2.7 ml, 6.81 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, the reaction mixture was cooled to 0 C., diluted with water (10 ml), acidified with 1N HCl to pH 5.0 and extracted with DCM (350 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography (eluent 8% MeOH:DCM), followed by recrystallization over acetonitrile gave the desired product (0.190 g, 26% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.1 (br.s., 1H), 7.34 (d, J=8.7 Hz, 2H), 7.28 (d, J=8.4 Hz, 2H), 6.31 (s, 1H), 6.14 (s, 1H), 4.41-4.34 (m, 1H), 3.07-2.98 (m, 1H), 2.90-2.72 (m, 4H), 2.42-2.24 (m, 2H), 2.14-2.02 (m, 2H), 2.0-1.82 (m, 3H), 1.80-1.56 (m, 5H), 1.52 (s, 3H), 1.47-1.42 (m, 1H), 1.44 (s, 3H), 1.41-1.33 (m, 2H), 1.31-1.23 (m, 2H), 1.27 (s, 3H), 1.22-1.16 (m, 1H), 1.18 (s, 3H), 1.15-1.0 (m, 8H), 0.97-0.79 (m, 16H); ESI MS: m/z 791.5 (M+H).sup.+; HPLC: 98.3%.

Example 6: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-((1-(4-chlorophenyl)cyclopropyl)methyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(35) ##STR00080##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-((1-(4-chloro phenyl)cyclopropyl)methyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a, 5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(36) ##STR00081##

(37) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.404 mmol, 1.0 eq) in THF (10 ml) was added DIPEA (0.96 ml, 5.616 mmol, 4.0 eq) and N.sup.1-((1-(4-chlorophenyl)cyclopropyl)methyl)-N.sup.2,N.sup.2-dimethylethane-1,2-diamine (Intermediate-6, 0.7 g, 2.808 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (15 ml) and extracted with DCM (350 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 4% MeOH in DCM as an eluent to obtain the desired product (0.8 g, 59% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.35 (m, 5H), 7.24 (m, 4H), 5.16, 5.10 (ABq, J.sub.AB=12.3 Hz, 2H), 4.46 (dd, J=11.1, 4.5 Hz, 1H), 3.70-3.43 (m, 2H), 3.37-3.20 (m, 1H), 3.20-3.04 (m, 2H), 2.95-2.75 (m, 3H), 2.73-2.60 (m, 1H), 2.58-2.42 (m, 2H), 2.41-2.29 (m, 2H), 2.23-2.0 (m, 8H), 1.99-1.80 (m, 3H), 1.80-1.70 (m, 3H), 1.67-1.50 (m, 4H), 1.50-1.25 (m, 5H), 1.35 (s, 3H), 1.25-1.18 (m, 6H), 1.09 (s, 3H), 1.05 (m, 1H), 0.97 (s, 3H), 0.93 (s, 3H), 0.91 (s, 3H), 0.90-0.82 (m, 10H), 0.79 (m, 1H); ESI-MS: m/z 964.53 (M+H).sup.+.

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-((1-(4-chloro phenyl)cyclopropyl)methyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(38) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-((1-(4-chlorophenyl)cyclopropyl)methyl)-3-(2-(dimethylamino)ethyl)ureido)-1-isopropyl-5a,5b, 8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.8 g, 0.829 mmol, 1.0 eq) in MeOH (16 ml) and THF (16 ml) was added aqueous 2.5N KOH solution (2.5 ml, 6.21 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, reaction mixture was diluted with water (15 ml), cooled to 0 C., pH adjusted to 6.0 with 1N HCl and extracted with DCM (330 ml). The combined organic extracts were washed with water (30 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-6% methanol in dichloromethane gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to obtain the solid. To this solid compound, MTBE (10 ml) was added and heated to reflux for about 30 minutes. The mixture was cooled to 0 C., filtered and was washed with n-hexane (5 ml) and dried under vacuum to obtain the desired product (0.12 g, 16.5% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.24 (m, 4H), 4.48 (dd, J=11.1, 4.5 Hz, 1H), 3.60-3.24 (m, 3H), 3.23-3.05 (m, 2H), 2.92-2.72 (m, 3H), 2.62-2.38 (m, 4H), 2.26 (m, 1H), 2.20 (s, 6H), 2.08-1.92 (m, 2H), 1.88-1.67 (m, 4H), 1.65-1.47 (m, 4H), 1.45-1.35 (m, 2H), 1.37 (s, 3H), 1.33-1.18 (m, 4H), 1.22 (s, 3H), 1.20 (s, 3H), 1.14-0.98 (m, 2H), 1.08 (s, 3H), 1.06 (s, 3H), 0.96-0.78 (m, 17H); ESI-MS: m/z 874.51 (M+H).sup.+.

Example 7: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(39) ##STR00082##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate

(40) ##STR00083##

(41) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.40 mmol, 1.0 eq) in THF (20 ml) was added DIPEA (0.725 g, 5.62 mmol, 4.0 eq) and (4-chlorophenyl)methanamine (0.394 g, 2.812 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (50 ml) and extracted with DCM (3100 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 6-8% methanol in DCM as an eluent to obtain the desired product (0.8 g, 67% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.40-7.35 (m, 4H), 7.35-7.25 (m, 3H), 7.18 (d, J=8.4 Hz, 2H), 5.15, 5.09 (ABq, J.sub.AB=12.6 Hz, 2H), 4.50-4.37 (m, 3H), 3.13-3.02 (m, 1H), 2.90-2.75 (m, 2H), 2.72-2.60 (m, 2H), 2.29 (d, J=15.6 Hz, 1H), 2.18-2.0 (m, 3H), 1.98-1.80 (m, 2H), 1.79-1.63 (m, 4H), 1.55-1.37 (m, 6H), 1.34 (s, 3H), 1.33-1.27 (m, 3H), 1.25 (s, 3H), 1.22-1.17 (m, 3H), 1.17-1.10 (m, 1H), 1.08 (s, 3H), 0.96 (s, 3H), 0.93 (s, 3H), 0.91 (s, 3H), 0.85 (s, 6H), 0.82-0.77 (m, 1H).

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen- 9-yl)oxy)carbonyl)-2,2-dimethyl cyclobutane-1-carboxylic acid

(42) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethyl cyclobutane-1,3-dicarboxylate (step 1, 0.8 g, 0.938 mmol, 1.0 eq) in MeOH (15 ml) and THF (15 ml) was added aqueous 2.5N KOH solution (2.81 ml, 7.04 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, reaction mixture was cooled to 0 C., acidified with 2N HCl and extracted with DCM (3150 ml). The combined organic extracts were washed with water, dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-3% MeOH in DCM gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to obtain the desired product (0.19 g, 26.57% yield) as an off-white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.2 (s, 1H), 7.35 (d, J=8.1 Hz, 2H), 7.24 (d, J=8.4 Hz, 2H), 6.32-6.23 (m, 2H), 4.42-4.32 (m, 1H), 4.27-4.15 (m, 2H), 3.12-3.02 (m, 1H), 2.85-2.72 (m, 3H), 2.46-2.42 (m, 2H), 2.38-2.25 (m, 1H), 2.17-2.08 (m, 2H), 2.0-1.83 (m, 3H), 1.75-1.30 (m, 9H), 1.27 (s, 3H), 1.23 (m, 2H), 1.20-1.07 (m, 8H), 1.05 (s, 3H), 0.93-0.87 (m, 9H), 0.82 (m, 7H); ESI-MS: m/z 785.46 (M+Na)+; HPLC: 98.4%.

Example 8: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-((1R,3S,5S)-3-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)-8-azabicyclo[3.2.1]octane-8-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(43) ##STR00084##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-((1R,3S,5S)-3-(3-isopropyl-5-methyl-4H, 2,4-triazol-4-yl)-8-azabicyclo[3.2.]octane-8-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(44) ##STR00085##

(45) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.40 mmol, 1.0 eq) in THF (15 ml) was added DIPEA (0.722 g, 5.6 mmol, 4.0 eq) and (1R,3S,5S)-3-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)-8-azabicyclo[3.2.1]octane (0.655 g, 2.8 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for about 16 hours. After completion of the reaction (monitored by TLC), the reaction mixture was diluted with water (50 ml) and extracted with EtOAc (350 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% methanol in DCM as an eluent to obtain the desired product (0.65 g, 49% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 7.36 (m, 5H), 6.49 (s, 1H), 5.12, 5.06 (ABq, 2H), 4.48-4.30 (m, 4H), 3.20-3.08 (m, 4H), 3.0-2.80 (m, 3H), 2.34 (s, 3H), 2.22-2.03 (m, 4H), 2.02-1.73 (m, 11H), 1.70-1.33 (m, 10H), 1.32-1.20 (m, 10H), 1.20-1.12 (m, 6H), 1.07-0.98 (m, 6H), 0.91 (s, 3H), 0.88-0.78 (m, 11H).

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-((1R,3S,5S)-3-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)-8-azabicyclo[3.2.1]octane-8-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclo butane-1-carboxylic acid

(46) To a suspension of wet 10% Pd/C (1.0 g) in EtOAc (70 ml) was added 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-((1R,3S,5S)-3-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)-8-azabicyclo[3.2.1]octane-8-carboxamido)-5a,5b,8,8,11a-penta methyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclo penta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.65 g, 0.68 mmol, 1.0 eq) in methanol (70 ml). To this stirred reaction mixture, ammonium formate (0.433 g, 6.87 mmol, 10.0 eq) was added portion wise and stirred for about 2 hours at room temperature. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with EtOAc and filtered through a pad of celite. The filtrate was washed with water; the organic layer was dried over Na.sub.2SO.sub.4, filtered and concentrated under reduced pressure. The crude compound was purified by silicagel column chromatography by using 10% methanol in DCM as an eluent to obtain the desired product (0.29 g, 49% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.1 (br.s., 1H), 6.50 (s, 1H), 4.50-4.25 (m, 4H), 3.18-2.93 (m, 4H), 2.83-2.72 (m, 2H), 2.48-2.42 (m, 1H), 2.34 (s, 3H), 2.30-2.04 (m, 4H), 2.04-1.70 (m, 11H), 1.68-1.50 (m, 5H), 1.47-1.33 (m, 5H), 1.28-1.20 (m, 10H), 1.17-1.02 (m, 6H), 1.04 (s, 3H), 1.02-0.98 (m, 1H), 0.91 (s, 6H), 0.88-0.78 (m, 10H); ESI-MS: m/z 856.58 (M+H).sup.+; HPLC: 95.7%.

Example 9: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(pyrrolidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(47) ##STR00086##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(pyrrolidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(48) ##STR00087##

(49) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.40 mmol, 1.0 eq) in THF (15 ml) was added N-(4-chlorobenzyl)-2-(pyrrolidin-1-yl)ethan-1-amine (Intermediate-7, 0.67 g, 2.81 mmol, 2.0 eq), followed by DIPEA (0.722 g, 5.62 mmol, 4.0 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (50 ml) and extracted with EtOAc (350 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 6% methanol in DCM as an eluent to obtain the desired product (0.5 g, 37% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.40-7.25 (m, 7H), 7.17 (d, J=7.1 Hz, 2H), 5.18-5.08 (m, 2H), 4.52-4.42 (m, 3H), 3.60-3.25 (m, 3H), 3.20-3.02 (m, 2H), 3.0-2.57 (m, 8H), 2.48-2.28 (m, 2H), 2.10-2.0 (m, 2H), 2.0-1.80 (m, 5H), 1.80-1.50 (m, 7H), 1.50-1.0 (m, 17H), 0.94 (s, 3H), 0.92-0.87 (m, 9H), 0.85 (m, 6H), 0.79 (m, 1H); ESI-MS: m/z 950.65 (M+H).sup.+.

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(pyrrolidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(50) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(pyrrolidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.5 g, 0.526 mmol, 1.0 eq) in THF (10 ml) and MeOH (10 ml) was added aqueous 2.5N KOH solution (1.57 ml, 3.95 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, reaction mixture was neutralized with 1N HCl and extracted with DCM (350 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-10% MeOH in DCM gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to give the desired product (0.06 g, 13% yield) as a white solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 7.37 (d, J=8.4 Hz, 2H), 7.21 (d, J=8.4 Hz, 2H), 4.44-4.32 (m, 3H), 3.43-3.36 (m, 2H), 3.20-3.03 (m, 3H), 2.88-2.72 (m, 3H), 2.57-2.40 (m, 7H), 2.37-2.07 (m, 6H), 2.0-1.83 (m, 3H), 1.80-1.52 (m, 9H), 1.52-1.31 (m, 5H), 1.27 (s, 3H), 1.26-1.21 (m, 1H), 1.17-1.08 (m, 7H), 0.96 (s, 3H), 0.93-0.89 (m, 4H), 0.86 (s, 3H), 0.84-0.79 (m, 6H); ESI-MS: m/z 860.57 (M+H).sup.+; HPLC: 96.8%.

Example 10: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-iso propyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-(3-(2-(5-phenyl-1H-imidazol-2-yl)propan-2-yl) ureido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(51) ##STR00088##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-(3-(2-(5-phenyl-1H-imidazol-2-yl)propan-2-yl)ureido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(52) ##STR00089##

(53) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 0.8 g, 1.124 mmol, 1.0 eq) in THF (30 ml) was added DIPEA (1.39 ml, 7.871 mmol, 7.0 eq) and 2-(5-phenyl-1H-imidazol-2-yl)propan-2-amine (Intermediate-8, 0.452 g, 2.249 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (200 ml) and extracted with DCM (3200 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 2% methanol in DCM as an eluent to obtain the desired product (0.4 g, 40% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.68-7.60 (m, 1H), 7.40-7.31 (m, 5H), 7.29-7.24 (m, 4H), 7.22 (s, 1H), 5.15, 5.09 (ABq, J.sub.AB=12.3 Hz, 2H), 4.48-4.39 (m, 1H), 3.18-3.08 (m, 1H), 2.83-2.72 (m, 3H), 2.70-2.53 (m, 2H), 2.28-2.10 (m, 3H), 1.98-1.77 (m, 5H), 1.74 (s, 3H), 1.70 (s, 3H), 1.68-1.36 (m, 7H), 1.34 (s, 3H), 1.33-1.18 (m, 6H), 1.17-1.10 (m, 7H), 1.05 (s, 3H), 0.96 (s, 3H), 0.89 (s, 3H), 0.84 (s, 3H), 0.83 (s, 3H), 0.78 (m, 1H).

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-(3-(2-(5-phenyl-1H-imidazol-2-yl)propan-2-yl)ureido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(54) To a suspension of wet 10% Pd/C (0.2 g) in EtOAc (10 ml) was added 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-(3-(2-(5-phenyl-1H-imidazol-2-yl)propan-2-yl)ureido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (step 1, 0.4 g, 0.438 mmol, 1.0 eq) dissolved in MeOH (10 ml). To this stirred reaction mixture, ammonium formate (0.138 g, 2.192 mmol, 5.0 eq) was added portion wise and stirred at room temperature for about 4 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was filtered through a pad of celite and was washed with EtOAc. The filtrate was evaporated under reduced pressure and purified by silicagel column chromatography by using 3% methanol in DCM as an eluent to obtain the desired product (0.025 g, 7% yield) as a white solid. .sup.1H NMR (300 MHz, CD.sub.3OD): ppm 7.65 (d, J=7.5 Hz, 2H), 7.40-7.21 (m, 4H), 4.42 (m, 1H), 3.10 (m, 1H), 2.93-2.75 (m, 3H), 2.66-2.40 (m, 2H), 2.22-2.13 (m, 2H), 2.07-1.89 (m, 4H), 1.84-1.75 (m, 2H), 1.70 (s, 3H), 1.69 (s, 3H), 1.67-1.39 (m, 7H), 1.38-1.20 (m, 3H), 1.34 (s, 3H), 1.20-1.13 (m, 6H), 1.12-1.06 (m, 3H), 1.01 (s, 3H), 0.98-0.93 (m, 4H), 0.91 (s, 3H), 0.88 (s, 6H), 0.87-0.83 (m, 1H); ESI-MS: m/z 823.52 (M+H).sup.+; HPLC: 94.9%.

Example 11: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(piperidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid hydrochloride

(55) ##STR00090##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(piperidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(56) ##STR00091##

(57) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.4 mmol, 1.0 eq) in THF (10 ml) was added DIPEA (1.23 ml, 7.0 mmol, 5.0 eq) and N-(4-chlorobenzyl)-2-(piperidin-1-yl)ethan-1-amine (Intermediate-9, 0.531 g, 2.1 mmol, 1.5 eq). The reaction mixture was stirred at room temperature for about 14 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with water (20 ml) and extracted with DCM (320 ml). The combined organic extracts were washed with brine solution (20 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% methanol in DCM as an eluent to obtain the desired product (0.7 g, 53.8% yield) as a brown color semi solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.38-7.22 (m, 7H), 7.17 (d, J=8.4 Hz, 2H), 5.18-5.08 (m, 2H), 4.50-4.40 (m, 3H), 3.40-3.30 (m, 1H), 3.20-3.08 (m, 2H), 3.05-2.90 (m, 1H), 2.90-2.60 (m, 5H), 2.50-2.25 (m, 7H), 2.12-1.90 (m, 7H), 1.83-1.68 (m, 3H), 1.50-1.0 (m, 22H), 1.0-0.82 (m, 18H), 0.82-0.79 (m, 1H).

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chloro benzyl)-3-(2-(piperidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid hydrochloride

(58) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-(3-(4-chlorobenzyl)-3-(2-(piperidin-1-yl)ethyl)ureido)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.7 g, 0.7 mmol, 1.0 eq) in MeOH (6 ml), THF (4 ml) and water (2 ml) was added potassium hydroxide (0.274 g, 4.9 mmol, 7.0 eq). The reaction mixture was stirred at room temperature for about 14 hours. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, cooled to 0 C., acidified with 1N HCl to pH-4 and extracted with DCM (320 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-10% MeOH in DCM gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to obtain the solid. To this solid compound, 1N HCl in 1,4-dioxane (5 ml) was added and stirred at room temperature for about 14 hours. The reaction mixture was evaporated under reduced pressure and dried under vacuum to obtain the desired product (0.2 g, 31% yield) as a white solid; .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 12.1 (br.s., 1H), 9.70 (br.s., 1H), 7.44 (d, J=8.1 Hz, 2H), 7.22 (d, J=8.1 Hz, 2H), 6.37 (s, 1H), 4.66, 4.55 (ABq, 2H), 4.40-4.30 (m, 1H), 3.80-3.68 (m, 1H), 3.50-3.40 (m, 3H), 3.18-3.10 (m, 2H), 2.92-2.60 (m, 5H), 2.42-2.05 (m, 3H), 1.97-1.50 (m, 13H), 1.50-1.0 (m, 22H), 0.91 (s, 3H), 0.90-0.78 (m, 12H), 0.67 (s, 3H); ESI-MS: m/z 874.6 (M-HCl+H).sup.+.

Example 12: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-iso propyl-3a-(4-(2-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)ethyl)piperazine-1-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethycyclobutane-1-carboxylic acid

(59) ##STR00092##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-(4-(2-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)ethyl)piperazine-1-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(60) ##STR00093##

(61) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-isocyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.40 mmol, 1.0 eq) in THF (20 ml) was added DIPEA (1.23 ml, 5.625 mmol, 4.0 eq) and 1-(2-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)ethyl)piperazine (Intermediate-10, 0.66 g, 2.81 mmol, 2.0 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was evaporated under reduced pressure, diluted with water (50 ml) and extracted with DCM (2100 ml). The combined organic extracts were washed with brine solution (50 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 5% methanol in DCM as an eluent to obtain the desired product (0.9 g, 69.2% yield) as a brown color solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.35 (m, 5H), 5.15, 5.09 (ABq, J.sub.AB=12.3 Hz, 2H), 4.47-4.42 (m, 1H), 3.96-3.87 (m, 2H), 3.46-3.30 (m, 4H), 3.18-3.08 (m, 3H), 3.0-2.73 (m, 7H), 2.70-2.57 (m, 2H), 2.52-2.43 (m, 3H), 2.40-2.20 (m, 2H), 2.10-2.03 (m, 1H), 2.0-1.82 (m, 3H), 1.80-1.58 (m, 5H), 1.58-1.20 (m, 17H), 1.20-1.15 (m, 3H), 1.10 (s, 3H), 1.08-1.0 (m, 1H), 0.98-0.80 (m, 19H); ESI-MS: m/z 949.7 (M+H).sup.+.

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-3a-(4-(2-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)ethyl)piperazine-1-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(62) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-iso propyl-3a-(4-(2-(3-isopropyl-5-methyl-4H-1,2,4-triazol-4-yl)ethyl)piperazine-1-carboxamido)-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.900 g, 0.948 mmol, 1.0 eq) in MeOH (18 ml) and THF (18 ml) was added aqueous 2.5N KOH solution (2.84 ml, 7.11 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, the reaction mixture was diluted with water (50 ml), cooled to 0 C., acidified with 1N HCl to pH-6 and extracted with DCM (350 ml). The combined organic extracts were washed with water (50 ml), dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 10% methanol in DCM as an eluent to obtain the desired product (30 mg, 3.6% yield) as a brown color solid. .sup.1H NMR (300 MHz, DMSO-d.sub.6): ppm 6.31 (s, 1H), 4.40-4.30 (m, 1H), 4.0-3.90 (m, 2H), 3.30-3.22 (m, 4H), 3.12-2.98 (m, 3H), 2.95-2.70 (m, 7H), 2.45-2.30 (m, 8H), 2.0-1.83 (m, 3H), 1.80-1.50 (m, 5H), 1.48-1.35 (m, 5H), 1.32-1.20 (m, 11H), 1.20-1.10 (m, 7H), 1.10-0.98 (m, 4H), 0.95-0.79 (m, 16H); ESI-MS: m/z 859.71 (M+H).sup.+.

Example 13: Preparation of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-iso propyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(pyrrolidin-1-ylmethyl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(63) ##STR00094##

Step 1: Synthesis of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(pyrrolidin-1-ylmethyl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate

(64) ##STR00095##

(65) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-3a-iso cyanato-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a, 11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclo butane-1,3-dicarboxylate (Intermediate-2, 1.0 g, 1.405 mmol, 1.0 eq) in THF (20 ml) at 0 C. was added (S)-1-(pyrrolidin-2-ylmethyl)pyrrolidine 2,2,2-trifluoroacetate (Intermediate-11, 1.697 g, 6.325 mmol, 4.5 eq) and N,N-diisopropylethylamine (2.44 ml, 14.05 mmol, 10.0 eq). The reaction mixture was stirred at room temperature for overnight. TLC indicated starting material was consumed and the desired product was observed. The reaction mixture was diluted with water (200 ml) and extracted with ethyl acetate (3200 ml). The combined organic extracts were dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-4% methanol in dichloromethane gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to obtain the desired product (1.058 g, 87% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 7.35 (m, 5H), 5.15, 5.09 (ABq, 2H), 4.50-4.42 (m, 1H), 3.72-3.61 (m, 1H), 3.50-3.25 (m, 2H), 3.20-3.05 (m, 2H), 3.0-2.88 (m, 1H), 2.87-2.70 (m, 3H), 2.70-2.60 (m, 2H), 2.50-2.20 (m, 3H), 2.20-2.0 (m, 3H), 1.80-1.50 (m, 10H), 1.50-1.40 (m, 6H), 1.40-1.20 (m, 17H), 1.13 (s, 3H), 1.10-1.0 (m, 1H), 0.96 (s, 3H), 0.94 (s, 3H), 0.92 (s, 3H), 0.87 (s, 3H), 0.85 (s, 3H), 0.85 (m, 1H); ESI-MS: m/z 866.70 (M+H).sup.+.

Step 2: Synthesis of (1R,3S)-3-((((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-isopropyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(pyrrolidin-1-ylmethyl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl)oxy)carbonyl)-2,2-dimethylcyclobutane-1-carboxylic acid

(66) To a stirred solution of 1-benzyl 3-((3aR,5aR,5bR,7aR,9S,11aR,11bR,13aS)-1-iso propyl-5a,5b,8,8,11a-pentamethyl-2-oxo-3a-((S)-2-(pyrrolidin-1-ylmethyl)pyrrolidine-1-carboxamido)-3,3a,4,5,5a,5b,6,7,7a,8,9,10,11,11a,11b,12,13,13a-octadecahydro-2H-cyclopenta[a]chrysen-9-yl) (1R,3S)-2,2-dimethylcyclobutane-1,3-dicarboxylate (step 1, 0.350 g, 0.40 mmol, 1.0 eq) in MeOH (7 ml) and THF (7 ml) was added aqueous 2.5N KOH solution (1.2 ml, 3.03 mmol, 7.5 eq). The reaction mixture was stirred at room temperature for about 16 hours. TLC indicated starting material was consumed and the desired product was observed. The organic phase was evaporated under reduced pressure, the reaction mixture was neutralized with 1N HCl and extracted with DCM (350 ml). The combined organic extracts were washed with water, dried over sodium sulfate, filtered and evaporated under reduced pressure. The residue was purified by silicagel column chromatography by using 0-10% methanol in DCM gradient. The fractions containing the expected product were combined and concentrated under reduced pressure to obtain the desired product (0.090 g, 28% yield) as a white solid. .sup.1H NMR (300 MHz, CDCl.sub.3): ppm 12.2 (br.s., 1H), 7.70 (s, 1H), 4.36 (m, 1H), 3.85-3.75 (m, 1H), 3.50-3.35 (m, 4H), 3.20-3.05 (m, 2H), 3.0-2.91 (m, 1H), 2.83-2.70 (m, 2H), 2.70-2.58 (m, 2H), 2.45-2.20 (m, 5H), 2.0-1.82 (m, 4H), 1.82-1.53 (m, 12H), 1.53-1.30 (m, 6H), 1.26 (s, 3H), 1.25-1.20 (m, 2H), 1.18-1.10 (m, 9H), 1.08-1.0 (m, 2H), 0.91 (s, 3H), 0.90 (s, 3H), 0.88 (s, 3H), 0.82 (s, 3H), 0.81 (s, 3H); ESI-MS: m/z 776.68 (M+H).sup.+; HPLC: 97.0%.

Pharmacological Activity

(67) The compounds described herein can be tested for their antiviral activity following procedures known to a person of ordinary skill in the art. For example, the following protocols can be employed for testing the compounds. These protocols are illustrative and do not limit to the scope of the invention.

Example 14: Evaluation of Compounds Antiviral Activity

(68) MT2 cells were infected with HIV-1 strain 92HT599 (10 TCID 50/30000 cells). The infected cells were plated at the concentration of 30,000 cells per well in 96 well plate. Test compound was added to the micro plate in defined format with the final concentration of DMSO (vehicle) is not more than 1%. Incubation was carried out in CO.sub.2 incubator for 96 hours for viral infection. At the end of incubation period an aliquot from each well was taken for p24 estimation. The quantitation of p24 is an index for antiviral activity of the compound. Percent inhibition was calculated with reference to control values (vehicle controls).

(69) P-24 estimation was carried out using Advance biosciences kit as per the procedure detailed by supplier.

(70) Results:

(71) For 0% serum binding assay, wherein A refers to an IC.sub.50 value of less than 5 nM, B refers to IC.sub.50 value in range of 5.01-10 nM, and C refers to IC.sub.50 values greater than 10 nM;

(72) For 40% serum binding assay, wherein A values refers to an IC.sub.50 value of less than 30 nM, B refers to IC.sub.50 value in range of 30.01-50 nM, and C refers to IC.sub.50 values greater than 50 nM. The IC.sub.50 (nM) values are set forth in Table-2.

(73) TABLE-US-00001 TABLE 1A 92HT599- Antiviral activity IC.sub.50 (nM) Example No. 0% 40% 1 A C 2 A A 3 B B 4 A C 5 A A 6 A B 7 B B 8 B C 10 A A 11 A B 12 C C 13 A C

REFERENCES

(74) 1. Antiviral methods and protocols (Eds: D Kinchington and R. F. Schinazi) Humana Press Inc., 2000. 2. HIV protocols (Eds: N. L. Michael and J. H. Kim) Humana Press Inc, 1999. 3. DAIDS Virology manual from HIV laboratories, Publication NIH-97-3838, 1997. 4. HIV-1 p.sup.24 antigen capture assay, enzyme immunoassay for detection of Human immunodeficiency Virus Type 1 (HIV-1) p24 in tissue culture mediaAdvanced bio science laboratories, Inc kit procedure.

(75) Although the invention herein has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It is therefore to be understood that numerous modifications may be made to the illustrative embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as described above.

(76) All publications and patent applications cited in this application are herein incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated herein by reference.