CN104030963A - Preparation method of bazedoxifene acetate crystal form A - Google Patents
Preparation method of bazedoxifene acetate crystal form A Download PDFInfo
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- CN104030963A CN104030963A CN201410302552.8A CN201410302552A CN104030963A CN 104030963 A CN104030963 A CN 104030963A CN 201410302552 A CN201410302552 A CN 201410302552A CN 104030963 A CN104030963 A CN 104030963A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D209/00—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom
- C07D209/02—Heterocyclic compounds containing five-membered rings, condensed with other rings, with one nitrogen atom as the only ring hetero atom condensed with one carbocyclic ring
- C07D209/04—Indoles; Hydrogenated indoles
- C07D209/10—Indoles; Hydrogenated indoles with substituted hydrocarbon radicals attached to carbon atoms of the hetero ring
- C07D209/12—Radicals substituted by oxygen atoms
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Abstract
Bazedoxifene is one of novel SERMs (Selective Estrogen Receptor Modulators) which are strictly screened, are specially used for preventing or treating osteoporosis of postmenopausal women and almost have no stimulation for breasts and uterus; just like other SERMs (tamoxifen and raloxifene), bazedoxifene takes double effects of excitement and antagonism for ER (Estrogen Receptor) in a target tissue. Preclinical and clinical experiments both prove that bazedoxifene has the characteristics of good curative effect, small side effect and strong specifity so as to be the first choice drug for treating and preventing woman postmenopausal osteoporosis in future. Compared with other crystal forms (B, C and D), a bazedoxifene acetate crystal form A has better solubleness and bioavailability and is the first choice crystal form on the market. The invention discloses a preparation method of the bazedoxifene acetate crystal form A, and the bazedoxifene acetate crystal form A is prepared by using the method.
Description
Technical field
The invention belongs to technical field of pharmaceutical chemistry, relate to a kind of preparation method of WAY 140424 acetate crystal form A.
Background technology
WAY 140424 acetate (bazedoxifene acetate, trade(brand)name: Conbriza), chemical name: 1-[4-(2-azepan-1-base-oxyethyl group)-benzyl]-2-(4-hydroxy phenyl)-3-Methyl-1H-indole-5-phenol acetic acid, structural formula is as follows:
WAY 140424 is in the third generation selective estrogen receptor modulators (SERMs) of research and development in 1997 by Hui Shi (wyeth) company, except having the result for the treatment of of front two generation SERMs for osteoporosis, it does not have the reaction that has hectic fever incidence to increase as raloxifene, to the stimulation of cardiovascular and mammary gland, all front two generation SERMs are little, substantially do not make the side effect of endometrial hyperplasia yet, determined curative effect, tolerance is high, toxic side effect is little, has wide market outlook.
WO 2010/118997 A1, WO 2011/022596 A2, US 5998402, US 6479535 disclose the synthetic method of WAY 140424 acetate, and the fusing point that is characterized as this salt is 176 ~ 178 ℃; US 7683051, US 2010/0310870 A1, EP 2311805 A1, WO 2005/100316 A1, WO 2009/102711 A1, WO 2009/102778 A1, WO 2010/151541 A1 have disclosed the preparation method of WAY 140424 acetate crystal form A, no matter in water or in the organic solvent of non-water, crystal form A all has the solvability better than crystal form B, this has improved the bioavailability of crystal form A, thereby is more conducive to distribution and the absorption of medicine in human body.But crystal form A is metastable-state crystal, and crystal form B is Thermodynamically stable crystal formation, crystal form A when (as the mixture of ethanol or ethanol and other solvent), is very easy to change into crystal form B or crystal formation D in organic solvent, so prepare purity, surpasses 99% crystal form A and has larger difficulty.
Therefore because WAY 140424 acetate crystal form A has better bioavailability in pharmaceutical preparation, commercially available crystal formation is polymorphic A, needs the preparation method of the preparation WAY 140424 acetate crystal form A that a kind of new, that circulation ratio is strong, yield and purity are high.In the above-mentioned disclosed method of preparing WAY 140424 acetate crystal form A, no matter be that direct salify (as US 7683051) still turns brilliant preparation its crystal form A (as WO 2009/102711 A1), circulation ratio is all lower, the present invention is compared to aforesaid method, favorable reproducibility, yield is higher, can prepare and not basically contain crystal form B, and crystal form A purity surpasses 99% WAY 140424 acetate crystal form A.
Summary of the invention
The object of the invention is to for the deficiencies in the prior art, a kind of preparation method of WAY 140424 acetate crystal form A is provided.This preparation method's favorable reproducibility, yield and purity are all higher.The method comprises:
A, the water content of Pd/C catalyzer is carried out to strict control;
B, at a certain temperature, under Pd/C catalyzer exists, hexamethylene imine benzyloxy indoles is contacted in organic solvent with hydrogen, obtaining comprising Abbado former times divides the first reaction mixture of free alkali, and this mixture is substantially containing hexamethylene imine benzyloxy indoles;
C, filtration Pd/C catalyzer, and add antioxidant to obtain the second reaction mixture in filtrate;
D, in the second reaction mixture, add Glacial acetic acid, stir and make WAY 140424 acetate crystal form B;
E, gained WAY 140424 acetate crystal form B purifying in step D is obtained to the highly finished product of crystal form B;
F, crystal form B is dissolved in organic solvent, is warming up to proper temperature and dissolves and make WAY 140424 acetate solution;
G, WAY 140424 acetate solution is chilled to proper temperature filters;
H, to the crystal seed that adds WAY 140424 acetate acetate crystal form A in filtrate;
I, the solution that comprises crystal seed is put in to lower for some time of room temperature;
J, the solution that comprises crystal seed is chilled to crystallization under certain temperature;
K, crystallization filter after for some time;
L, filtration cakes torrefaction are dried to obtain WAY 140424 acetate crystal form A.
As optimal way, in described steps A, Pd/C catalyzer is the irreducibility Pd on moistening carbon, and Pd content is 10%, and wherein the water content of Pd/C catalyzer is a key factor for separating out of WAY 140424 acetate crystal form A.The impact of the water content that table one has shown Pd/C catalyzer on crystallization.
Table one
| Method | The kind of Pd/C | Pd/C water content | Yield | Crystal type | Fusing point (℃) |
| 1 | 10%Pd/C | 7.7% | Cannot crystallization | ||
| 2 | 10%Pd/C | 47.5% | ? 60% | A+D | 164~165 |
| 3 | 10%Pd/C | 50.0% | ? 60% | A | 174~176 |
| 4 | 10%Pd/C | 53.7% | ? 63% | A | ?172~176 |
| 5 | 10%Pd/C | 55.0% | ? 75% | A | ?175~178 |
| 6 | 10%Pd/C | 56.0% | ? 70% | A | ?174~175 |
| 7 | 10%Pd/C | 66.0% | ? 45% | A+D | ?172~174 |
As optimal way, in described steps A, Pd/C catalyzer water content is controlled to 50% ~ 56% and can obtains the WAY 140424 acetate crystal form A that purity is higher when the crystallization.
As optimal way, in described step B, its temperature of reaction is carried out at approximately 50 ℃ ~ 55 ℃.
As optimal way, in described step B, its reaction pressure is carried out under 0.1Mpa.
As optimal way, in described step B, its reaction times is 4 ~ 5h.
As optimal way, in described step B, solvent is ethyl acetate-ethanol mixed system.
As optimal way, in described step C, while filtering Pd/C catalyzer, need constantly pass into argon gas.
As optimal way, in described step C, the oxidation inhibitor adding is vitamins C.
As optimal way, in described step D, solvent is ethyl acetate-ethanol mixed system.
As optimal way, in described step D, temperature of reaction is carried out at 50 ℃ ~ 55 ℃.
As optimal way, in described step D, the reaction times is 1 ~ 1.5h.
As optimal way, in described step e, solvent is alcohol-water-acetone mixed system.
As optimal way, in described step e, solvent temperature is 90 ~ 95 ℃.
As optimal way, in described step e, recrystallization temperature is-5 ~-0 ℃.
As optimal way, in described step e, the oxidation inhibitor adding is vitamins C.
As optimal way, in described step F, solvent is ethanol-acetone-hexanaphthene mixed system.
As optimal way, in described step F, solvent temperature is 90 ~ 95 ℃.
As optimal way, in described step F, the oxidation inhibitor adding is vitamins C.
As optimal way, in described step F, solvent temperature is 90 ~ 95 ℃.
As optimal way, in described step F, cooling solution temperature to 35 ~ 40 ℃
As optimal way, in described step F, during filtering solution, on filter paper, pad diatomite.
As optimal way, in described step G, filtering solution temperature is 35 ~ 40 ℃.
As optimal way, in described step H, while adding crystal seed, solution temperature is very large on the crystal type impact of finally separating out, and adds crystal seed can obtain different crystal types under different solution temperatures, and table two has shown this impact of step solution temperature on crystallization type.
Table two
| Solution temperature while adding crystal seed | Crystal type |
| -10℃-0℃ | Crystal formation D |
| 0℃-30℃ | The mixed crystal of crystal form A and crystal formation D |
| 30℃-40℃ | Crystal form A |
| 40℃-50℃ | The mixed crystal of crystal form A and crystal form B |
| 50℃-80℃ | Crystal form B |
As optimal way, in described step H, while adding crystal seed, solution temperature is controlled at 30 ~ 40 ℃.
As optimal way, in described step H, crystal seed is that uniform spreading is sprinkled upon in solution.
As optimal way, in described step I, described room temperature is 20 ~ 25 ℃.
As optimal way, in described step I, be 5 ~ 10min storage period.
As optimal way, in described step J, cooling solution temperature is to-5 ~-0 ℃.
As optimal way, in described step J, solution keeps stationary state, forbids stirring.
As optimal way, in described step J, the crystallization time is 5 ~ 6h.
As optimal way, in described step K, the washing with alcohol of 0 ~ 5 ℃ for filter cake during filtration.
As optimal way, in described step L, use the dry crystal form A of constant temperature drying under reduced pressure case, drying temperature is 50 ~ 55 ℃, be 5 ~ 6h time of drying, is kept in the dry environment of 5 ℃ ~ 25 ℃.
The present invention adopts raw material cheap and easy to get, with easy experimental implementation, has prepared efficiently WAY 140424 acetate crystal form A, and gained crystal form A purity reaches 99%, and indices all reaches pharmacopeia requirement.
Contriver has carried out a large amount of research to the preparation method of WAY 140424 acetate crystal form A, by experiment many times, the discovery that we are surprised, when adopt the present invention to record WAY 140424 acetate crystal form A preparation method time, this preparation method has reached the technique effect out of expection on the whole.
Beneficial effect of the present invention is: the inventive method combines cleverly existing method and prepares WAY 140424 acetate crystal form A, and having found the great effect of Pd/C catalyzer water content to crystallization, preparation technology is with the obvious advantage, simple to operate, favorable reproducibility, purity and yield are higher.
Embodiment
Disclosed all features in this specification sheets, or the step in disclosed all methods or process, except mutually exclusive feature and/or step, all can combine by any way.
Embodiment 1: the preparation of WAY 140424 free alkali III
In 10% Pd/C, add distilled water wash twice, filter out part distilled water to control its water content 50 ~ 56%; By 20g(0.031mol) 5-benzyloxy-2-(4-benzyloxy phenyl)-3-methyl isophthalic acid-[4-(2-azepan-1-base oxethyl) benzyl]-1H-indoles II is dissolved in 120ml ethyl acetate and 40ml ethanol, add the above-mentioned Pd/C of 13.5g, be heated to 50 ~ 55 ℃, stirring reaction 4 ~ 5h under 0.1MPa, TLC monitoring has been reacted.Under argon shield, filter out Pd/C, solution directly adds mcg vitamin C to become acetate with acetic acid, yield 100% at 50 ~ 55 ℃
Embodiment 2: the preparation of WAY 140424 acetate I
Filtrate in embodiment 1 is placed in to 250ml reaction flask, adds mcg vitamin C, vacuumize, argon replaces 1 ~ 2 time, is warming up to 50 ℃ ~ 55 ℃, drips 2.06g(0.034mol) Glacial acetic acid is to reaction solution, at 50 ℃ ~ 55 ℃, stir 1 ~ 1.5h, stirring at room 2h, filters to obtain off-white color solid, washing with alcohol solid 1 ~ 2 time, dry to obtain 12.11g off-white color solid, yield 83.7%, HPLC:99.67%, mp177-180 ℃.
Embodiment 3: WAY 140424 acetate I refining
In the 12.11g solid of drying, add 83.8ml ethanol, 51.2 ml acetone, 10.48ml water and mcg vitamin C, reflux until solid all molten clear after slow coolings to room temperature, after putting into refrigerator (5 ~-0 ℃) and spending the night, filtering drying obtains 9.81g off-white color solid, yield 81.2%, HPLC:99.86%, mp178-180 ℃.
Embodiment 4: the preparation of WAY 140424 acetate crystal form A
Taking 1.06g(0.002mol) WAY 140424 acetate is in 21.2ml Denatured alcohol (ethanol: cyclohexane: acetone=95:3:5), adding 0.02332g(0.00039mol) Glacial acetic acid and mcg vitamin C post-heating reflux solid is molten clear, interior temperature is cooled to 40 ~ 45 ℃, heat filtering at 35 ~ 40 ℃ (is used diatomite, in filtering type solution, temperature is at 40 ~ 45 ℃, after filter, without solid, separate out), solution is cooled to 30 ~ 40 ℃, add crystal seed A, standing lower slow cooling, at 25 ℃, after 5 ~ 10min, start crystallize out, continue afterwards the crystal of separating out a large amount of WAY 140424 at slow cooling to 0 ℃, at-5 ~ 0 ℃, after standing 5 ~ 6h, filter, filter cake is dried for 1 ~ 2 time afterwards with the washing with alcohol washing of 0 ~ 5 ℃, time of drying 5 ~ 6h, 50 ℃ ~ 55 ℃ of drying temperatures, obtain 0.8g WAY 140424 acetate crystal form A, yield 75.5%, HPLC:99.88%, mp176 ~ 178 ℃.
The present invention is not limited to aforesaid embodiment.The present invention expands to any new feature or any new combination disclosing in this manual, and the arbitrary new method disclosing or step or any new combination of process.
Claims (9)
1. a method of preparing WAY 140424 acetate crystal form A, the method comprises the following steps:
(a) at a certain temperature, under Pd/C catalyzer exists, hexamethylene imine benzyloxy indoles II is reacted in suitable organic solvent with hydrogen, and filter Pd/C under oxidation inhibitor exists after, obtain the free alkali III filtrate of WAY 140424;
(b) in filtrate, add acetic acid salify to obtain WAY 140424 acetate crystal form B;
(c) under oxidation inhibitor exists, the mixed crystal of WAY 140424 acetate crystal form B or WAY 140424 acetate crystal form A and crystal form B is dissolved in the solvent that contains ethanol, and this solvent is warming up to proper temperature makes it dissolve formation solution;
(d) solution is cooled to after suitable temp, separate out WAY 140424 acetate crystal form A, filters and the dry WAY 140424 acetate crystal form A that obtains higher degree under suitable condition.
2. the method for a kind of WAY 140424 acetate crystal form A according to claim 1, is characterized in that, in described step (a), Pd/C catalyzer water content is 50% ~ 56%.
3. the method for a kind of WAY 140424 acetate crystal form A according to claim 1, is characterized in that, in described step (a), organic solvent is the mixed system of ethyl acetate and ethanol.
4. the method for a kind of WAY 140424 acetate crystal form A according to claim 1, is characterized in that, in described step (b), adds oxidation inhibitor during filtration in solution.
5. the method for a kind of WAY 140424 acetate crystal form A according to claim 1, is characterized in that, in described step (c), institute's rising temperature is: 90 ~ 95 ℃.
6. the method for a kind of WAY 140424 acetate crystal form A according to claim 1, is characterized in that, in described step (d), adds oxidation inhibitor in solution.
7. according to the method for a kind of WAY 140424 acetate crystal form A described in claim 1-6, it is characterized in that, in described step (c), solvent is to take ethanol as main body, and the mixed solvent by one or more solvents such as ethyl acetate, acetone, hexanaphthene, suberane carries out sex change to it and makes.
8. the method for a kind of WAY 140424 acetate crystal form A according to claim 1, is characterized in that, in described step (d), suitable temp is :-10 ~-5 ℃.
9. according to the method for a kind of WAY 140424 acetate crystal form A described in claim 1-8, it is characterized in that, wherein said being dried carried out in constant temperature drying under reduced pressure case, and drying temperature is at 50 ~ 55 ℃, time of drying 5 ~ 6h, thereby keep the stability of WAY 140424 acetate crystal form A.
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104529864A (en) * | 2014-12-26 | 2015-04-22 | 华润赛科药业有限责任公司 | Preparation method of bazedoxifene acetate crystal form A |
| CN105669518A (en) * | 2014-12-04 | 2016-06-15 | 上海医药集团股份有限公司 | Preparation method of bazedoxifene acetate and crystal form A |
| CN106631971A (en) * | 2016-12-19 | 2017-05-10 | 齐鲁天和惠世制药有限公司 | Preparation method of bazedoxifene acetate |
| CN107628982A (en) * | 2016-07-19 | 2018-01-26 | 苏州立新制药有限公司 | Bazedoxifene acetate polymorphic A preparation method |
| CN111004165A (en) * | 2019-12-03 | 2020-04-14 | 南京正济医药研究有限公司 | Preparation method of bazedoxifene acetate crystal form A |
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| CN1938272A (en) * | 2004-04-07 | 2007-03-28 | 惠氏公司 | Crystalline polymorph of bazedoxifene acetate |
| WO2009102771A1 (en) * | 2008-02-11 | 2009-08-20 | Wyeth | Methods of converting polymorphic form b of bazedoxifene acetate to polymorphic form a of bazedoxifene acetate |
| CN101977897A (en) * | 2008-02-11 | 2011-02-16 | 惠氏有限责任公司 | Methods of preparing polymorphic form a of bazedoxifene acetate |
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| CN1938271A (en) * | 2004-04-07 | 2007-03-28 | 惠氏公司 | Crystalline polymorph of bazedoxifene acetate |
| CN1938272A (en) * | 2004-04-07 | 2007-03-28 | 惠氏公司 | Crystalline polymorph of bazedoxifene acetate |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105669518A (en) * | 2014-12-04 | 2016-06-15 | 上海医药集团股份有限公司 | Preparation method of bazedoxifene acetate and crystal form A |
| CN105669518B (en) * | 2014-12-04 | 2019-06-04 | 上海医药集团股份有限公司 | The preparation method of bazedoxifene acetate and its A crystal form |
| CN104529864A (en) * | 2014-12-26 | 2015-04-22 | 华润赛科药业有限责任公司 | Preparation method of bazedoxifene acetate crystal form A |
| CN104529864B (en) * | 2014-12-26 | 2017-01-25 | 华润赛科药业有限责任公司 | Preparation method of bazedoxifene acetate crystal form A |
| CN107628982A (en) * | 2016-07-19 | 2018-01-26 | 苏州立新制药有限公司 | Bazedoxifene acetate polymorphic A preparation method |
| CN107628982B (en) * | 2016-07-19 | 2021-03-23 | 苏州立新制药有限公司 | Preparation method of bazedoxifene acetate polycrystalline type A |
| CN106631971A (en) * | 2016-12-19 | 2017-05-10 | 齐鲁天和惠世制药有限公司 | Preparation method of bazedoxifene acetate |
| CN106631971B (en) * | 2016-12-19 | 2019-02-12 | 齐鲁天和惠世制药有限公司 | A kind of preparation method of bazedoxifene acetate |
| CN111004165A (en) * | 2019-12-03 | 2020-04-14 | 南京正济医药研究有限公司 | Preparation method of bazedoxifene acetate crystal form A |
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Application publication date: 20140910 |