The synthetic method of WAY 140424
(1) technical field
The invention belongs to technical field of medicine synthesis, particularly, the present invention relates to the synthetic method for the treatment of postmenopausal osteoporosis medicine WAY 140424.
(2) technical background
WAY 140424, English name Bazedoxifene, an indole derivatives, its chemistry 1-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-2-(4-hydroxy phenyl)-3-Methyl-1H-indole-5-phenol by name.Its chemical structural formula is as follows:
WAY 140424 is developed by Wyeth at first, is third generation selective estrogen receptor modulators.In April, 2009, commodity were called Conbriza, are used for the treatment of postmenopausal osteoporosis in Italy and Spain's listing.
The WAY 140424 synthetic method of current bibliographical information mainly contains two.
1, EP0802183, JP1998036346, US5998402 is that starting raw material replaces through ethyl bromoacetate with p-Hydroxybenzylalcohol, sulfur oxychloride chloro obtains ethyl 2-(4-(chloromethyl) phenoxy group) acetic ester, ethyl 2-(4-((5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole-1-base) methyl) phenoxy group) acetic ester is generated again with the reaction of intermediate 5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole, through bromo, a word used for translation ring in heptan replaces, deprotection obtains WAY 140424.Synthetic route is as follows:
There is following shortcoming in this route:
(1) on indoles N, substitution reaction productive rate is low, and the reagent sodium hydride used not easily is preserved
(2) there is to LAH active agent hidden danger such as preserving safety equally in reduction
(3) during indole synthesis, productive rate is low, only has 50%-60%, and after indoles cyclization, also have four-step reaction, and initial charging capacity is increased, and improves synthesis cost.
(4) impurity of a word used for translation ring in heptan modification reaction generation is wayward, and in the end a few step carries out the difficulty that modification directly can increase finished product purifying.
2, EP1025077, WO9919293 is that starting raw material replaces through 1-(2-chloroethyl) a word used for translation ring in heptan with p-Hydroxybenzaldehyde, sodium borohydride reduction, sulfur oxychloride chloro obtains 1-(2-(4-(chloromethyl) phenoxy group) ethyl) a word used for translation ring in heptan, react with intermediate 5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole again and generate 1-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole, last deprotection obtains WAY 140424.Synthetic route is as follows:
This route carries out the shortcoming that a word used for translation ring in heptan is modified after solving previous routes, but still there is following deficiency:
(1), during the sodium borohydride reduction of phenyl aldehyde reacts, the sodium borohydride equivalents of use is high, and cancellation needs the plenty of time and produces a large amount of flammable explosive hydrogen, there is potential safety hazard
(2) on indoles N, substitution reaction productive rate is low, and the reagent sodium hydride used not easily is preserved
Above two kinds of methods all use intermediate 5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole, and its syntheti c route is as follows
This reaction yield only has 50%-60% should not be placed on route first half.
(3) summary of the invention
The present invention improves on the route basis that forefathers provide, and object there are provided a kind of new synthetic method, and overall yield is high, easy and simple to handle, and synthesis cost is low.
In order to reach above-mentioned requirements, the present invention adopts a word used for translation ring in heptan (1) for raw material is through 1, 2-ethylene dibromide (2) replaces afterwards and p-Hydroxybenzaldehyde (3) is obtained by reacting intermediate 4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenyl aldehyde (4), intermediate (4) and 4-(benzyloxy) aniline (5) reduction amination generate key intermediate N-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-4-(benzyloxy) aniline (6), intermediate (6) and 1-(4-(benzyloxy) phenyl)-2-monobromethane-1-ketone (7) cyclization generate 1-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole (8), intermediate (8) deprotection obtains finished product WAY 140424.Without any bibliographical information before this route, concrete synthetic route is as follows:
The beneficial effect of present method is:
(1) adopt glycol dibromide to replace chlorine, add the activity of substitution reaction
(2) intermediate (4) and (5) reduction amination generate intermediate (6), and reaction conditions is gentle, and productive rate is high, and purifying is convenient
(3) adopt intermediate (6) and (7) cyclization, shorten reactions steps, improve overall conversion.
(4) route is avoided using sodium hydride, the inflammable and explosive active agent such as Lithium Aluminium Hydride
(5) there is no bibliographical information before this method, there is novelty, the protection of Yuan Yan house journal can be got around.
(4) embodiment
Below by specific embodiment, this invention is further described.
Embodiment 1: the synthesis the first step of intermediate 4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenyl aldehyde (4): the synthesis of intermediate 1-(2-bromotrifluoromethane) a word used for translation ring in heptan (2)
In 2L there-necked flask, add a word used for translation ring in heptan (1) 100g, glycol dibromide (2) 246.2g, and salt of wormwood 208.9g, finally add acetonitrile 1.25L, treats allly to mix post-heating 100 degree reaction.After TLC detection reaction terminates, reaction solution is cooled to room temperature, crosses and filter salt of wormwood, filtrate decompression is removed organic solvent, steam residual 800mL methylene dichloride to dissolve, wash with water 2-3 time, after anhydrous sodium sulfate drying, decompression removing methylene dichloride obtains oily 185.5g, productive rate 89.1%
Second step: the synthesis of intermediate 4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenyl aldehyde (4)
In 2L there-necked flask, add 1-(2-bromotrifluoromethane) a word used for translation ring in heptan (2) 100g, p-Hydroxybenzaldehyde (3) 77.02g, and salt of wormwood 100.57g, finally add acetonitrile 1.0L, treats allly to mix post-heating 50 degree reaction.After TLC detection reaction terminates, reaction solution is cooled to room temperature, crosses and filter salt of wormwood, filtrate decompression is removed organic solvent, steam residual 800mL methylene dichloride to dissolve, with washing with water 2-3 time, after anhydrous sodium sulfate drying, decompression removing methylene dichloride obtains product 111.5g, productive rate 93.0%
Embodiment 2: the synthesis of intermediate N (4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-4-(benzyloxy) aniline (6)
4-(benzyloxy) aniline (5) 50.0g is added in 1L there-necked flask, 4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenyl aldehyde (4) 74.4g, use 500mL dissolve with ethanol, reaction system ice-water bath is cooled to 0-5 degree, slowly add sodium triacetoxy borohydride 106.3g in batches, add rear reaction solution and be warming up to 35 degree, stirring reaction.TLC detection reaction terminates rear reaction solution and is cooled to 0-5 degree, slowly adds water 200mL wherein, and add stirring two lab scale, layering, abandons aqueous phase, and organic phase obtains product 85.5g through purification by silica gel column chromatography, productive rate 79.2% after concentrating and doing
The synthesis of embodiment 3:1-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole (8)
N-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-4-(benzyloxy) aniline (6) 5.0g is added in 25mL single port bottle, 1-(4-(benzyloxy) phenyl)-2-monobromethane-1-ketone (7) 9.2g, and triethylamine 2.9g, with 4mLN, dinethylformamide dissolves, stir lower heating 120 degree reaction, TLC detection reaction terminates rear reaction solution and is cooled to 0-5 degree, pour in 20mL water, after being extracted with ethyl acetate, in methyl alcohol, recrystallization obtains solid 10.3g, productive rate 55.0%.
Embodiment 4: the synthesis of WAY 140424
1-(4-(2-(a word used for translation ring in heptan-1-base) oxyethyl group) phenmethyl)-5-(benzyloxy)-2-(4-(benzyloxy) phenyl)-3-Methyl-1H-indole (8) 5.0g is added in 100mL single port bottle, dissolve with 38mL Glacial acetic acid, add palladium carbon 500mg, react under hydrogen, after TLC detection reaction terminates, suction filtration removing palladium carbon, filtrate decompression is except desolventizing, the crude product obtained obtains WAY 140424 1.6g through silica gel column chromatography, productive rate 44.4%