Processes for the preparation of prostaglandin amides

Abstract

The subject of the invention is process for the preparation of the prostaglandin amides of the general formula I, ##STR00001## where in the formula the bonds marked with dotted lines may be single or double bonds, in the case of double bounds at positions 5,6 and 13,14 they may be in cis or in trans orientation, Q stands for a hydroxyl-group and Z stands for a hydroxyl- or oxo-group, R.sup.1 and R.sup.2 independently represent hydrogen atom or a straight or branched C.sub.1-10 alkyl- or aralkyl-group, optionally substituted with ONO.sub.2 group, or an aralkyl- or aryl-group, which contains heteroatom, R.sup.3 represents a straight or branched, saturated or unsaturated C.sub.4-6 hydrocarbon group, or a C.sub.4-10 alkylcycloalkyl- or cycloalkyl-group, or an optionally with alkyl group or halogen atom substituted phenyl-, C.sub.7-10 alkylaryl- or hetaryl-group, Y represents (CH.sub.2).sub.n group or O atom or S atom, and where n=0-3.

Claims

1. A process for preparing crystal form II of bimatoprost of formula (IB), comprising: ##STR00037## adding 20-60 mass % protic solvent to a reaction mixture containing bimatoprost, to any crystalline or non-crystalline form of bimatoprost, or to mixtures thereof; stirring and/or scratching the resulting mixture; and drying the resulting mixture; wherein the protic solvent comprises alcohols and/or water; and wherein the alcohols comprise methanol or ethanol.

2. The process according to claim 1, wherein drying is performed in vacuum, at a temperature between 25-50 C.

3. The process according to claim 1, wherein 35 mass % amount of protic solvent is applied.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the IR spectrum of the lactoltriol of example 1a.

(2) FIG. 2 shows the IR spectrum of the obtained Bimatoprost acid.

(3) FIG. 3 presents the IR spectrum of crystal form I.

(4) FIG. 4 presents the IR spectrum of crystal form II. obtained in the process according to the invention.

(5) FIG. 5 presents the DSC curve of crystal form I.

(6) FIG. 6 presents the DSC curve of crystal form II. obtained in the process according to the invention.

(7) FIG. 7 presents the X-ray powder diffraction curve of crystal form I.

(8) FIG. 8 presents the X-ray powder diffraction curve of crystal form II. obtained in the process according to the invention.

(9) FIG. 9 shows the X-ray powder diffraction curve of the obtained Bimatoprost acid.

(10) FIG. 10 shows the DSC curve of the obtained Bimatoprost acid.

(11) FIG. 11A shows the MS spectrum for positive ionization of Example 5.

(12) FIG. 11B shows the MSMS (precursor ion: 438.26) data of Example 5.

(13) In the process according to the invention we use calculated amount, favourably 20-60 mass %, preferably 35 mass % amount of protic solvent, especially alcohols like methanol, ethanol and/or water. Preferably water is used as protic solvent.

(14) As mechanical effect we apply stirring or scratching, or both. The added solvent is removed by drying. Drying is performed at a temperature between () 60 C. and 70 C., especially at 35 C., in vacuum.

(15) As ether-type solvent we apply calculated amount, preferably 2000-8000 mass % amount of dimethyl ether, diethyl ether, diisopropyl ether, preferably diethyl ether. The added solvent is removed by drying. Drying is performed at low temperature, preferably between 0-()50 C. by passing through nitrogen gas.

(16) Identification of the products was carried out with the help of the following analytical instruments:

(17) NMR spectra were recorded by Bruker-Avance III-500 MHz instrument, DSC curves by Mettler-Toledo DSC 1/700 instrument, IR spectra by Perkin-Elmer Spektrum 400 FT-IR spectrophotometer, MS spectra by Shimadzu LC-MS-IT-TOF instrument. Melting points were determined by BUM Melting Point B-545 apparatus.

(18) Further details of the invention are described in the examples, without to limit the invention to the examples.

EXAMPLES

1. Preparation of the Starting Material

a.) Preparation of the [1,1-Biphenyl]-4-carboxylic acid ((3aR,4R,5R,6aS)-hexahydro-4-[(1E,3 S)-3-hydroxy-5-phenyl-1-penten-1-yl]-2-hydroxy-2H-cyclopenta[b]furan-5-yl) ester (PPB-lactoltriol)

(19) The lacton group of 55 g of [1,1-Biphenyl]-4-carboxylic acid ((3aR,4R,5R,6aS)-hexahydro-4-[(1E,3S)-3-hydroxy-5-phenyl-1-penten-1-yl]-2-oxo-2H-cyclopenta[b]furan-5-yl) ester (PPB-lactondiol)

(20) ##STR00016##
is reduced in 1000 ml of tetrahydrofuran (THF) solvent at ()65-()85 C. with the hexane solution of 422 ml diisobutyl aluminium hydride (DIBAL-H). The reaction mixture is destroyed with NaHSO.sub.4 solution, the aqueous phase is extracted with ethyl acetate, the organic phase is washed with NaHCO.sub.3 solution and the solvent is removed at 40-50 C. The crude material is evaporated to obtain 46.2 g oil.

(21) Structural formula of the obtained PPB-lactoltriol:

(22) ##STR00017##

(23) From the crude oil after crystallization in tert-butyl methyl ether (TBME): hexane mixture, 41.6 g white crystals are obtained.

(24) Melting point: 91.1-91.7 C.

(25) IR spectrum of the lactoltriol of example 1a. is shown in FIG. 1.

(26) .sup.13C and .sup.1H NMR data:

(27) ##STR00018##

(28) TABLE-US-00001 Number of the Position .sup.13C (ppm) .sup.1H (ppm) protons Multiplicity Coupling (Hz) 6; OH 99.72; 100.64 5.57* (20H); 5.49 1 m J.sub.6,OH = 4.65; 3.6 OH: 6.05; 6.28 1 d 7 38.14; 38.44 2.57* (32H); 1.77 (39H) 1; 1 m; m 2.3-2.9; 7.0; 1.78* (39H) J.sub.7,7 = 14.0 8 46.26; 45.69 2.57* (32H); 2.43 1 m ; J.sub.8,9 = 8.85-9.1 9 80.19; 80.92 4.60; 4.50 1 m J.sub.8,9 = 9.1; 2.7-3.3; 7.3-7.4; J.sub.9,10 = 5.25 10 40.12**; 40.37** 1.98; 1.93; 1; 1 m; m J.sub.9,10 = 5.5; 2.69; J.sub.10,10 = 13.6-13.65 11; OR 80.54; 79.03 5.12; 5.05 1 m 7.1-7.3 7.4-7.55; 9.8 12 54.12; 53.22 2.55* (33H); 3.11 1 m ; 9.85-10.1; 7.55 13 129.38; 129.62 5.59* (19-20H); 5.59* (19-20H) 1 m 6.3; J.sub.13,14 = 15.3 14 136.66; 136.69 5.65* (17-18H); 5.65* (17-18H) 1 m J.sub.14,15 = 5.15; J.sub.13,14 = 15.45 15; OH 70.47; 70.39 3.98* (28H); 3.98* (28H) 1 m J.sub.14,15 = 5.2-5.5 OH: 4.80* (24H); 4.79* (25H) 1 d J.sub.15,OH = 4.7; 4.8 16 40.09** 1.71-1.61* (40H) 1; 1 m; m 17 31.86; 31.80 2.57* (32H); 2.55* (33H) 2 m 18 143.14 19, 19 129.06 7.10; 7.06 1 d J.sub.19,20 = 7.3; 7.2 20, 20 129.09 7.23* (9H); 7.20* (10H) 1 t J.sub.19,20 = J.sub.20,21 = 7.4; 7.5 21 126.41; 126.37 7.14* (11H); 7.13* (12H) 1 t J.sub.20,21 = 7.3-7.45 22 166.07; 166.16 23 129.52; 129.48 24, 24 130.71 8.04* (2H); 8.06* (1H) 1 d J.sub.24,25 = 8.3; 8.4 25, 25 127.86 7.83* (3H); 7.81* (4H) 1 d J.sub.24,25 = 8.5; 8.4 26 145.64 27 139.77 28, 28 127.90 7.75* (5H); 7.73* (6H) 1 d J.sub.28,29 = 7.6; 7.95 29, 29 130.01 7.55 1 t J.sub.28,29 = J.sub.29,30 = 7.4-7.8 30 129.33 7.47 1 t J.sub.29,30 = 7.3-7.35 *Overlapping .sup.1H NMR signals (The number in brackets signifies the position number of the signal group in the PMR spectrum, direction: towards decreasing shifts) **.sup.13C NMR signals overlapping with the multiplett of the DMSO solvent.

b.) Preparation of the (3aR,4R,5R,6aS)-hexahydro-4-[(1E,3S)-3-hydroxy-5-phenyl-1-penten-1-yl]-2H-cyclopenta[b]furan-2,5-diol, (lactoltriol)

(29) 46.2 g of [1,1-Biphenyl]-4-carboxylic acid ((3aR,4R,5R,6aS)-hexahydro-4-[(1E,3S)-3-hydroxy-5-phenyl-1-penten-1-yl]-2-hydroxy-2H-cyclopenta[b]furan-5-yl) ester (PPB-lactoltriol) oil is dissolved in 230 ml of methanol and after adding 6.6 g of K.sub.2CO.sub.3 it is desacylated at 35-45 C. The pH of the reaction mixture is adjusted to 7-8 at ()5-0 C. with 0.5 M phosphoric acid solution. The precipitated crystals are filtered off and washed with methanol:water mixture. The mother liquor is evaporated, extracted with ethyl acetate, the organic phase is dried over Na.sub.2SO.sub.4, the drying material is filtered off and the product is crystallized by the addition of hexane. 26 g of white crystalline material is obtained.

(30) Structural Formula of the Product:

(31) ##STR00019##

(32) Melting point: 98-103 C.

(33) .sup.13C and .sup.1H NMR data:

(34) ##STR00020##

(35) TABLE-US-00002 Number of the Position .sup.13C (ppm) .sup.1H (ppm) protons Multiplicity Coupling (Hz) 6; OH 99.65; 100.48 5.46* (8H); 5.40 1 m J.sub.6,OH = 4.65; 3.8 OH: 5.92; 6.13 1 d 7 39.94; 38.77 1.81* (26H) 1; 1 m; m 1.97* (25H); 1.66* (27H) 8 45.63; 45.81 2.29* (22H); 2.22* (24H) 1 m 9 79.20; 80.97 4.38; 4.32 1 m J.sub.9,10a = 6.9; 7.3-7.55 10 41.53; 43.795 2.27* (23H); 1.48 1; 1 m; m J.sub.9,10a = 6.4-6.8; 7.1-7.4 2.30* (22H); 1.76* (27H) 11; OH 77.62; 77.06 3.70; 3.61 1 m J.sub.11,OH = 5.95; 5.85 OH: 4.75; 4.80 1 d 12 56.80; 55.86 1.97* (25H); 2.53* (21H) 1 m 13 131.46; 132.11 5.54* (6H); 5.54* (6H) 1 m J.sub.13,14 = 15.3 14 135.39; 135.16 5.49* (7H); 5.49* (7H) 1 m J.sub.13,14 = 16 15; OH 71.14; 71.22 3.94* (16H); 3.94* (16H) 1 m J.sub.15,OH = 4.75; 4.35 OH: 4.72* (12H); 4.71* 1 d (13H) 16 40.26 1.74* (27H); 1.66* (27H) 1; 1 m; m 17 32.24; 32.27 2.63* (20H); 2.63* (20H) 1; 1 m 18 143.23 21* 129.20 7.22* (2H) 1 d J.sub.21,22 = 7.3 22* 129.18 7.30 1 t J.sub.21,22 = J.sub.22,23 = 7.4-7.6 23* 126.48 7.19* (3H) 1 t J.sub.22,23 = J.sub.23,24 = 7.25 24* 129.18 7.30 1 t J.sub.23,24 = J.sub.24,25 = 7.4-7.6 25* 129.20 7.22* (2H) 1 d J.sub.24,25 = 7.3 *Overlapping .sup.1H NMR signals. (The number in brackets signifies the position number of the signal group in the PMR spectrum, direction: towards decreasing shifts).

c.) Preparation of the 7-[(1R,2R,3R,5S)-3,5-dihydroxy-2-[(1E,3S)-3-hydroxy-5-phenyl-1-penten-1-yl]-cyclopentyl]-5-heptenic acid, (5Z)-(bimatoprost acid)

(36) c1.) 108 g of 4-carboxybutylphosphonium bromide (KBFBr) is dissolved in 800 ml of THF and the solution is cooled to 0-(5) C. To this solution first 91 g of potassium tert-butylate (KOtBu), and then after stirring and cooling to (10)-(15) C., the solution of 25 g of lactoltriol in THF are added. When the expected conversion is reached the reaction mixture is destroyed with water, then EtOAc is added. The aqueous phase is washed with EtOAc. The aqueous layer is acidified with NaHSO.sub.4 solution to pH=2 and extracted with EtOAc. The united organic phase is washed with 15% NaCl solution, dried over Na.sub.2SO.sub.4, filtered and evaporated. The residue is crystallized from the mixture of ethyl acetate and diisopropyl ether. The crystals are filtered off and washed, the filtrate solution is evaporated. The resulting yellow oil is purified by chromatography on silica gel using diisopropyl ether-acetone eluent. 25.5 g oil is obtained.

(37) IR spectrum of the obtained Bimatoprost acid is shown in FIG. 2.

(38) c2.) The product obtained in example 1/c1.) is dissolved in 60 ml of isopropyl-acetate and under stirring 40 ml of diethyl-ether is added to it. Small amount of bimatoprost acid seeding crystal is added to the reaction mixture. Under stirring gradually cooled to 0 C. about 60 ml of diisopropyl-ether is added to it. The suspension is stirred at this temperature for a night thereafter it is filtered and washed with diisopropyl-ether and dried under vacuum. 20.4 g crystalline bimatoprost acid is obtained.

(39) DSC curve of the obtained Bimatoprost acid is shown in FIG. 10 and X-ray powder diffraction curve in FIG. 9.

(40) Structural Formula of the Product:

(41) ##STR00021##

(42) Melting point: 63.0-65.5 C.

(43) .sup.13C and .sup.1H NMR data:

(44) ##STR00022##

(45) TABLE-US-00003 Number of the Position .sup.13C (ppm) .sup.1H (ppm) protons Multiplicity Coupling (Hz) 1; COOH 175.30 ; COON: 12.02 ; COOH: 1 ; COOH: broad 2 34.10 2.23* (21H); 2.16* (22H) 1; 1 m; m 3 25.45 1.54* (26H) 2 m 4 27.09 2.01* (24H) 2 m J.sub.4,5 = 6.8-7.0 5 129.53 5.29 1 td J.sub.4,5 = 7.2 J.sub.5,6 = 10.8 6 130.64 5.50* (7H) 1 td J.sub.6,7 = 7.8 J.sub.5,6 = 10.6 7 25.74 2.15* (22H); 2.04* (24H) 1; 1 m; m 8 49.81 1.34 1 m J.sub.8,9 = 5.75 9; OH 70.47 3.95* (13H); OH: 4.40 1 m; broad J.sub.8,9 = 5.75 10 44.89 2.24* (21H); 1.48* (26H) 1; 1 m; ddd J.sub.10,10 = 14.1; 5.65-5.85; 2.3-2.4 11; OH 76.69 3.71; OH: 4.55 1; OH: 1 m (ddd); broad J.sub.11,12 = 7.5 12 55.22 2.19* (21H) 1 m 13 133.05 5.40* (7H) 1 dd J.sub.12,13 = 7.7-8.15; J.sub.13,14 = 15.45 14 136.09 5.47* (7H) 1 dd J.sub.14,15 = 6.2-6.35; J.sub.13,14 = 15.4 15; OH 71.53 3.94* (13H); OH: 4.71 1; OH: 1 m; broad J.sub.14,15 = 6.4 16 40.45* 1.75* (25H); 1.69* (25H) 1; 1 m; m 17 32.29 2.64 2 m 18 143.24 19* 129.15 7.21* (5H) 1 d J.sub.19,20 = 6.9 20* 129.20 7.30 1 t J.sub.19,20 = J.sub.20,21 = 7.5-7.55 21* 126.51 7.19* (5H) 1 t J.sub.20,21 = J.sub.21,22 = 6.7-7.3 22* 129.20 7.30 1 t J.sub.21,22 = J.sub.22,23 = 7.5-7.55 23* 129.15 7.21* (5H) 1 d J.sub.22,23 = 6.9 *Partly or fully overlapping .sup.1H NMR signals. (The number in brackets signifies the position number of the signal group in the PMR spectrum, direction: towards decreasing shifts).

2. Preparation of 7-[3,5-Dihydroxy-2-(3-hydroxy-5-phenyl-pent-1-enyl)-cyclopentyl]-5-heptenoic acid (2,5-dioxo-pyrrolidin-1-yl) ester (activated ester)

(46) 27.5 g of bimatoprost acid of example 1/c2.) is dissolved in 270 ml of THF and to it are added at room temperature 13.7 g of N,N-diisopropylcarbodiimide followed by 13.7 g of N-hydroxysuccinimide. The mixture is stirred at that temperature and then poured onto the mixture of 1N NaHSO.sub.4 solution and tert-butyl methyl ether (TBME). The phases are separated. The organic phase is washed with 1N NaHCO.sub.3 solution, the aqueous-alkaline phase is extracted with TBME. The united organic phase is dried over Na.sub.2SO.sub.4, filtered and evaporated. The residue is crystallized from hexane:acetone mixture to obtain 30.04 g white crystalline material.

(47) Product:

(48) ##STR00023##

(49) Melting point: 93.5-103.4 C.

3

(50) 27.5 g of bimatoprost acid of example 1/c1.) is dissolved in 270 ml of THF and to this solution are added at room temperature 11.5 g of potassium carbonate and 19.6 g of N,N-disuccinimidyl carbonate. The reaction mixture is under stirring gradually heated to 60 C. and then poured onto the mixture of 1N NaHSO.sub.4 solution and tert-butyl methyl ether (TBME). The phases are separated, the organic phase is washed with 1N NaHCO.sub.3 solution and the aqueous-alkaline phase is extracted with TBME. The united organic phase is dried over Na.sub.2SO.sub.4, filtered and evaporated. The residue is crystallized from hexane:acetone mixture to obtain 30.9 g white crystalline material.

(51) Product:

(52) ##STR00024##

(53) Melting point: 93.5-103.4 C.

(54) .sup.13C and .sup.1H NMR data:

(55) ##STR00025##

(56) TABLE-US-00004 Coupling constant (Hz) Numbering .sup.13C (ppm) .sup.1H (ppm) Number of .sup.1H Multiplicity (+/0.2 Hz) 1 168.80 2 29.70 2.55** 2 t J.sub.2,3 = 7.4 3 24.29 1.61*** 2 m (tt) J.sub.3,4 = 7.4 4 25.70 2.06 2 m J.sub.4,5 = 7.2 5 127.87 5.28 1 dt J.sub.5,6 = 10.7 6 130.27 5.48.sup.+ 1 dt (ddd) J.sub.6,7 = 7.4 7 24.83 7a: 2.14.sup.++ 1 m 7b: 2.00 1 m 8 48.78 1.32 1 m (dddd) 10.4; 10.4; 5.1; 5.1 9 69.53 3.915.sup.+++ 1 m 9-OH 4.35 1 d J.sub.9,OH = 5.0 10 43.94 : 2.20.sup.++ 1 m(ddd) J.sub.gem = 14.1; 8.2; 5.9 : 1.44 1 ddd 5.6; 2.3 11 75.37 3.68 1 m (dddd) ~7.9; ~7.9; ~5.8; ~5.8 11-OH 4.50 1 d J.sub.11,OH = 5.8 12 54.22 2.16.sup.++ 1 m 7.8; 3.8 13 132.02 5.37 1 dd J.sub.13,14 = 15.4; J.sub.12,13 = 8.1 14 135.16 5.44.sup.+ 1 m (dd) J.sub.14,15 = 6.3 15 70.56 3.909.sup.+++ 1 m 15-OH 4.65 1 d J.sub.15,OH = 4.7 16 39.49* 1.71*** 1 m 1.65*** 1 m 17 31.35 2.60** 2 m 18 142.31 19, 23 128.19/128.24 7.17.sup.# 2 d J.sub.19,20 = 7.4 20, 22 128.24/128.19 7.26 2 t J.sub.20,21 = 7.4 21 125.55 7.15.sup.# 1 t 24, 27 170.18 25, 26 25.42 2.80 4 s *Overlapped .sup.13C NMR by the DMSO signal. **,***,.sup.+,.sup.++,.sup.+++,.sup.#Overlapped .sup.1H NMR signals.

4.) Preparation of 7-[3,5-Dihydroxy-2-(3-hydroxy-5-phenyl-pent-1-enyl)-cyclopentyl]-5-heptenoic acid 1,3-dioxo-1,3-dihydro-isoindol-2-yl ester (activated ester)

(57) 2 g of bimatoprost acid is dissolved in 20 ml of THF and to this solution are added at room temperature 1 g of N-hydroxy-phtalimide and 1 ml of N,N-diisopropylcarbodiimide. The reaction mixture is stirred for 2 hours and then poured onto the mixture of 1N NaHSO.sub.4 solution and tert-butyl methyl ether (TBME). The phases are separated, the organic phase is washed with 1N NaHCO.sub.3 solution and the aqueous-alkaline phase is extracted with TBME. The united organic phase is dried over Na.sub.2SO.sub.4, filtered and evaporated. The residue is crystallized from hexane:acetone mixture to obtain 1.5 g white crystalline material.

(58) Product:

(59) ##STR00026##

(60) Melting point: 83.2-84.5 C.

(61) .sup.13C and .sup.1H NMR data:

(62) ##STR00027##

(63) TABLE-US-00005 Coupling constant (Hz) Numbering .sup.13C (ppm) .sup.1H (ppm) Number of .sup.1H Multiplicity (+/0.2 Hz) 1 169.82 2 29.63 2.64 2 t J.sub.2,3 = 7.4 3 24.29 1.65* 2 m (tt) J.sub.3,4 = 7.4 4 25.71 2.09 2 m J.sub.4,5 = 7.2 5 127.84 5.30 1 dt J.sub.5,6 = 10.5 6 130.33 5.50 1 dt (ddd) J.sub.6,7 = 7.5 7 24.83 a: 2.16** 1 m J.sub.gem = 12.6 b: 2.01 1 m (ddd) 8 48.79 1.325 1 m (dddd/tt) 10.7, 10.0; 5.3; 4.7 9 69.52 3.92*** 1 m 9-OH 4.38 1 d J.sub.9,OH = 4.9 10 43.95 : 2.205** 1 m(ddd) J.sub.gem = 14.1; J.sub.10 = 8.4 and 6.0 : 1.44 1 ddd J.sub.10 = 5.6 and 2.1 11 75.74 3.68 1 m (dddd/tt) ~7.8; ~7.8; ~6.0; ~6.0 11-OH 4.52 1 d J.sub.11,OH = 5.8 12 54.23 2.165** 1 m 13 132.08 5.37 1 dd J.sub.13,14 = 15.4; J.sub.12,13 = 8.3 14 135.18 5.44 1 m (dd) J.sub.14,15 = 6.4 15 70.56 3.89*** 1 m 15-OH 4.66 1 d J.sub.15,OH = 4.6 16 39.47.sup.$ a: 1.69* 1 m b: 1.64* 1 m 17 31.34 2.58** 2 m (td) 10.1 and 6.3 18 142.28 19, 23 128.16.sup.$/128.20 7.15.sup.+ 2 d J.sub.19,20 = 7.5 20, 22 128.20/128.16.sup.$ 7.24 2 t J.sub.20,21 = 7.3 21 125.52 7.13.sup.+ 1 t 24, 31 161.81 25, 30 ~128.1.sup.$ 26, 29 123.97 7.97.sup.++ 2 m 27, 30 135.51 7.94.sup.++ 2 m .sup.$Overlapped .sup.13C NMR by the DMSO signal. .sup.$$Overlapped .sup.13C NMR signals. *,**,***,.sup.+,.sup.++Overlapped .sup.1H NMR signals.

5.) Preparation of 7-[(1R,2R,3R,5S)-3,5-dihydroxy-2-[(1E,3S)-3-hydroxy-5-phenyl-1-pentenyl]-cyclopentyl]-N-ethyl-5-heptenamide, (5Z()bimatoprost) through the activated ester

(64) 27.5 g of bimatoprost acid is dissolved in 270 ml of THF and to the solution are added at room temperature 13.7 g N,N-diisopropylcarbodiimide and then 13.7 g of N-hydroxysuccinimide. The mixture is stirred at room temperature. The resulting activated ester is not isolated.

(65) ##STR00028##

(66) After the completion of the ester formation 70 ml of 2M ethylamine in THF solution is added to the reaction mixture. The mixture is stirred until the expected conversion is reached, then it is poured onto the mixture of 1N NaHSO.sub.4 solution and tert-butyl methyl ether (TBME). The phases are separated, the organic phase is washed with 1N NaHCO.sub.3 solution and the aqueous-alkaline phase is extracted with TBME. The united organic phase is dried over Na.sub.2SO.sub.4, filtered and evaporated to obtain 25.4 g of oil.

(67) Product:

(68) ##STR00029##

(69) .sup.13C and .sup.1H NMR data:

(70) ##STR00030##

(71) TABLE-US-00006 Number of Coupling (Hz) Position .sup.13C (ppm) .sup.1H (ppm) the protons Multiplicity (+/0.2 Hz) 1 172.51 2 35.88 2.02** 2 t J.sub.2,3 = 7.5 3 26.27 1.53*** 2 m (tt) J.sub.3,4 = 7.5 4 27.25 1.99** 2 m J.sub.4,5 = 7.2 5 129.78 5.30 1 dt J.sub.5,6 = 10.5 6 130.38 5.48.sup.+ 1 Dt (ddd) 7 25.72 2.15.sup.++ 1 m 2.03** 1 m 8 49.78 1.35 1 m (dddd) 10.6; 10.6; 4.7; 4.7 9 70.45 3.95.sup.+++ 1 m 9-OH 4.40 1 d J.sub.9,OH = 4.9 10 44.85 : 2.23.sup.++ 1 m : 1.48*** 1 ddd J.sub.gem = 14.2; 5.5; 2.2 11 76.67 3.71 1 m (dddd) ~7.5; ~7.5; ~7.5; 6.5 11-OH 4.54 1 d J.sub.11,OH = 5.8 12 55.15 2.19.sup.++ 1 m 13 132.91 5.41 1 dd J.sub.13,14 = 15.4; J.sub.12,13 = 8.0 14 136.00 5.47.sup.+ 1 M (dd) 15 71.41 3.94.sup.+++ 1 m 15-OH 4.71 1 d J.sub.15,OH = 4.6 16 40.36* 1.74.sup.# 1 m 1.70.sup.# 1 m 17 32.25 2.61 1 m 2.675 1 m 18 143.21 19, 23 129.13 7.21.sup.## 2 d J.sub.19,20 = 7.4 20, 22 129.15 7.30 2 t J.sub.20,21 = 7.4 21 126.46 7.19.sup.## 1 t 24 (NH) 7.72 1 broad, t J.sub.24,25 = 5.5 25 34.13 3.07 2 qd J.sub.25,26 = 7.2 26 15.70 1.02 3 t

(72) The MS spectrum for positive ionization is shown in FIG. 11A.

(73) Expected formula:

(74) C.sub.25H.sub.37NO.sub.4

(75) Measured exact mass: 438.2648 [M+Na]+

(76) Expected exact mass: 438.2615 [M+Na]+ M=3.3 mDa and 7.53 ppm

(77) C.sub.25H.sub.35NO.sub.3 (M-H.sub.2O)

(78) Measured exact mass: 398.2655 [M-H.sub.2O+H]+

(79) Expected exact mass: 398.2690 [M-H.sub.2O+H]+ M=3.5 mDa and 8.79 ppm

(80) The MSMS (precursor ion: 438.26) data is shown in FIG. 11B.

(81) Expected formula:

(82) C.sub.25H.sub.35NO.sub.3 (M-H.sub.2O)

(83) Measured exact mass: 420.2520 [M-H2O+Na]+

(84) Expected exact mass: 420.2509 [M-H2O+Na]+ M=1.1 mDa and 2.62 ppm

(85) C.sub.25H.sub.32NO.sub.3 (M-H.sub.2O-5H)

(86) Measured exact mass: 394.2366 [M-H.sub.2O-5H]+

(87) Expected exact mass: 394.2377 [M-H.sub.2O-5H]+ M=1.1 mDa and 2.79 ppm

(88) C.sub.25H.sub.30NO.sub.2 (M-2H.sub.2O-5H)

(89) Measured exact mass: 376.2258 [M-2H.sub.2O-5H]+

(90) Expected exact mass: 376.2271 [M-2H.sub.2O-5H]+ M=1.3 mDa and 3.46 ppm

6.) Preparation of Bimatoprost Through the Activated Ester

(91) 27.5 g of bimatoprost acid is dissolved in 270 ml of THF and to this solution are added at room temperature 11.5 g of potassium carbonate and 19.6 g of N,N-disuccinimidyl carbonate. The reaction mixture is gradually heated to 60 C. under stirring. The resulting activated ester is not isolated.

(92) ##STR00031##

(93) After the formation of the activated ester, 70 ml of 2M ethylamine in THF solution is added to the reaction mixture. When the reaction is completed the mixture is poured onto the mixture of 1N NaHSO.sub.4 solution and EtOAc. The organic phase is washed with 1N NaHCO.sub.3 solution, the aqueous-alkaline phase is extracted with EtOAc. The united organic phase is washed with NaCl solution and dried over Na.sub.2SO.sub.4. The drying material is filtered off, the filtrate is evaporated to obtain 25.7 g of oil.

(94) Product:

(95) ##STR00032##

7.) Preparation of Bimatoprost Through the Activated Amide

(96) 27.5 g bimatoprost acid is dissolved in 270 ml of pyridine and 13.7 g of 1,1-carbonyldiimidazole is added to it. The mixture is stirred at 20-25 C. until the activated amide formation takes place. The resulting activated amide is not isolated.

(97) ##STR00033##

(98) 70 ml of 2M ethylamine in THF solution is added to the reaction mixture at room temperature and the mixture is stirred until the expected conversion is reached. The mixture is then poured onto the mixture of 1N NaHSO.sub.4 solution and tert-butyl methyl ether (TBME). The phases are separated, the organic phase is washed with 1N NaHCO.sub.3 solution and the aqueous-alkaline phase is extracted with TBME. The united organic phase is dried over Na.sub.2SO.sub.4, filtered and the filtrate is evaporated to obtain 23.82 g of oil.

(99) Product:

(100) ##STR00034##

8.) Preparation of Bimatoprost from the Purified Activated Ester

(101) 30.9 g of the activated ester according to Example 3. is dissolved in 270 ml of THF and to this solution 70 ml of 2M ethylamine dissolved in THF is added. After the completion of the reaction the mixture is poured onto the mixture of 1N NaHSO.sub.4 solution and EtOAc. The organic phase is washed with 1N NaHCO.sub.3 solution. The aqueous-alkaline phase is extracted with EtOAc. The united organic phase is washed with NaCl solution and dried over Na.sub.2SO.sub.4. The drying material is filtered off and the filtrate is evaporated. To the resulting oil 35 mass % of water is added and the product is crystallized. 24.8 g of white bimatoprost crystals of higher than 99.5% purity are obtained.

(102) Product:

(103) ##STR00035##

(104) Melting point: 71.9-72.5 C.

(105) HPLC: 99.6% bimatoprost, less than 0.3% trans-bimatoprost, 0.1% other impurity

9.) Preparation of Bimatoprost According to Method iii.)

(106) 2.00 g of Bimatoprost acid is dissolved in 20 ml of tetrahydrofuran (THF) and at 30 C. first 1.29 g of 2-chloro-1,3-dimethylimidazolinium chloride (DMC) and 1.44 ml of triethylamine, then after 10 minutes of stirring 2.57 ml of 2M ethylamine in THF solution are added. The reaction mixture is gradually, in 1 hour, heated to 70 C. and the mixture is stirred at that temperature until the starting material disappears (approx. 1 hour). The reaction is followed by TLC.

(107) After the completion of the reaction the mixture is poured onto the mixture of 1N NaHSO.sub.4 solution and isopropyl acetate (iPrOAc). The organic phase is washed with 1N NaHCO.sub.3 solution, the aqueous-alkaline phase is extracted with iPrOAc. The united organic phase is washed with NaCl solution and dried over Na.sub.2SO.sub.4. The drying material is filtered off and the filtrate is evaporated to obtain 1.41 g of oil.

(108) Product:

(109) ##STR00036##

10.) Preparation of Crystal Form II. of Bimatoprost from Crude Bimatoprost Oil

(110) To the bimatoprost oil prepared according to Example 6, 35 mass % amount of purified water is added. The mixture is intensively stirred and then dried in vacuum at max. 35 C. temperature, while every 2 hour it is agitated and scratched. After complete dryness the mixture is homogenized. IR spectrum of this product is shown in FIG. 4 and the DSC curve of this product is shown in FIG. 6. The X-ray diffraction curve of produced Form II is shown in FIG. 8.

(111) Yield: 96.9%

(112) Mp.: 78 C.

(113) DSC onset: 73.56 C.

11.) Preparation of Crystal Form II. of Bimatoprost

(114) The crude bimatoprost prepared according to Example 5. is dissolved under heating in 3000-fold amount of diethyl ether. The solvent is then removed at ()20-()30 C. by slowly passing through nitrogen gas. The resulting crystals are homogenized, or first exposed to mechanical effect and then homogenized.

(115) Yield: 94.4%

(116) Mp.: 75.9 C.

(117) DSC onset: 72.92 C.

12.) Preparation of Crystal Form II. of Bimatoprost

(118) To the crude bimatoprost prepared according to Example 6, 35 mass % amount of methanol is added. The mixture is intensively stirred and then dried in vacuum at max. 35 C. temperature, while every 2 hour it is agitated and scratched. After complete dryness the mixture is homogenized.

(119) Yield: 95.8%

(120) Mp.: 77.2 C.

(121) DSC onset: 73.07 C.

13.) Preparation of Crystal Form II of Bimatoprost

(122) To the crude bimatoprost prepared according to Example 6, 17.5 mass % amount of purified water and 17.5 mass % amount of ethanol are added. The mixture is intensively stirred and then dried in vacuum at max. 35 C. temperature, while every 2 hour it is agitated and scratched. After complete dryness the mixture is homogenized.

(123) Yield: 92.3%

(124) Mp.: 72.9 C.

(125) DSC onset: 72.96 C.

14

a.) Preparation of Bimatoprost Crystal Form I. (According to Example 38 of Patent Application US 20090163596)

(126) 5.2 g of crude bimatoprost is crystallized from 106 g of acetonitrile: the mixture is heated to a temperature near the boiling point, the hot solution is cooled to room temperature and the mixture is stirred at that temperature for 1 hour, then at 0-5 C. for 2 hours. The precipitated crystals are filtered off, washed with 20 g of cold (0-5 C.) acetonitrile and dried in vacuum at 0-5 C. for 1 hour, at room temperature for half an hour and at 30-40 C. for 2 hours.

(127) 4.3 g of crystal form I. of bimatoprost is obtained. Its IR spectrum is shown in FIG. 3, its DSC curve is shown in FIG. 5 and its X-ray diffraction curve of Form I is shown in FIG. 7.

(128) Yield: 83%

(129) Mp.: 62.1 C.

(130) DSC onset: 63.61 C.

b.) Preparation of Bimatoprost Crystal Form II. Started from Form I

(131) To crystal form I. of bimatoprost prepared according to Example 14a, 35 mass % amount of purified water is added. The mixture is intensively stirred and then dried in vacuum at max. 35 C. temperature, while every 2 hour it is agitated and scratched. After complete dryness the mixture is homogenized.

(132) Yield: 97.3%

(133) Mp.: 77.7 C.

(134) DSC onset: 73.14 C.

15.) Preparation of Crystal Form II. of a Mixture of Bimatoprost Crystal Form II. and I

(135) To a 50%-50% mixture of crystal form II. and I. of bimatoprost 35 mass % amount of purified water is added. The mixture is intensively stirred and then dried in vacuum at max. 35 C. temperature, while every 2 hour it is agitated and scratched. After complete dryness the mixture is homogenized.

(136) Yield: 97.6%

(137) Mp.: 78.2 C.

(138) DSC onset: 73.77 C.