INTERMEDIATES FOR THE PREPARATION OF (3R, 4S)-1-(4-FLUOROPHENYL)-3-[(3S)-3-(4-FLUOROPHENYL)-3-HYDROXYPROPYL)]-4-(4-HYDROXYPHENYL)-2-AZETIDINONE
申请人:Stepankova Hana
公开号:US20110046389A1
公开(公告)日:2011-02-24
A method for the preparation of (S)-alcohol oxazolidides of general formula II, in which PG represents hydrogen or a hydroxyl protecting group, such as trimethylsilyl, tert-butyldimethylsilyl, benzyloxycarbonyl, tert-butoxycarbonyl, benzyl, benzhydryl or trityl, in which a ketal oxazolidide of general formula III, where PG has the same meaning as above and R means an alkyl with 1-4 carbon atoms, linear or branched, such as methyl, ethyl, isopropyl or butyl, or R+R together represents a divalent alkyl, or substituted with 1 or 2 alkyl groups, e.g. 1,2-ethylene, 1,2-propylene, 1,2-butylene, 1,3-propylene or 2,2-dimethyl-1,3-propylene, is deprotected by the action of acidic reagents in a mixture of water and a water-miscible solvent in the temperature range of 0 to 100° C. (stage A), and the obtained ketone oxazolidide of general IV, in which PG has the same meaning as above, is reduced with asymmetrical reagents in an inert organic solvent in the temperature range of −30 to +40° C. (stage B).
一种制备通式II的(S)-醇噁唑烷二酮的方法,其中PG代表氢或羟基保护基,例如三甲基硅基、叔丁基二甲基硅基、苄氧羰基、叔丁氧羰基、苄基、苄基亚甲基或三苄基,其中通式III的酮缩醛噁唑烷二酮,其中PG具有与上述相同的含义,R表示具有1-4个碳原子的直链或支链烷基,例如甲基、乙基、异丙基或丁基,或者R+R一起表示双价烷基,或被1或2个烷基基团取代,例如1,2-乙烯基、1,2-丙烷基、1,2-丁烷基、1,3-丙烷基或2,2-二甲基-1,3-丙烷基,通过在0至100°C的温度范围内的水和水溶性溶剂混合物中用酸性试剂脱保护(阶段A),并且在惰性有机溶剂中在-30至+40°C的温度范围内用不对称试剂还原得到的通式IV的酮缩醛噁唑烷二酮,其中PG具有与上述相同的含义(阶段B)。