申请人:Pfizer Inc.
公开号:US04952694A1
公开(公告)日:1990-08-28
A novel three-step process for resolving a racemic spiro-hydantoin compound into its optical antipodes is disclosed, which involves (1) reacting said racemic compound with an optically-active asymmetric isocyanate of the formula RNCO, wherein R is (S)- or (R)-1-phenylethyl or (S) or (R)-1-(1-naphthyl)ethyl, to form the corresponding diastereomeric uredio compound; (2) separating the resulting diastereomeric mixture into its component parts, and (3) thereafter converting the separated ureido diastereomers obtained in step (b) to the corresponding asymmetric hydantoin compounds by treatment with an alkali metal lower alkoxide (C.sub.1 -C.sub.4), followed by acidification, whereupon the desired optical isomer is obtained. The final products so obtained, such as (4S)-(+)-6-fluoro-2,3-dihydro-spiro[4H-1-benzopyran-4,4'-imidazolidine]-2' , 5'-dione (sorbinil) and (5'S)-3'-chloro-5', 6', 7', 8'-tetra-hydro-spiro[imidazolidine-4,5'-quinoline]-2,5-dione, are known to be useful in preventing or alleviating certain chronic diabetic complications. The aforementioned diastereomeric uredio intermediates are novel compounds.
揭示了一种用于将一个混合氨基酸螺环脲化合物分离成其光学对映体的新颖三步过程,包括(1)将该混合氨基酸与一种光学活性不对称异氰酸酯(化学式为RNCO,其中R为(S)-或(R)-1-苯乙基或(S)或(R)-1-(1-萘基)乙基)反应,形成相应的二对映异构脲化合物;(2)将得到的二对映混合物分离成其组分;(3)然后通过用碱金属低碱度物(C.sub.1 -C.sub.4)处理,随后酸化,将在步骤(2)中获得的分离的脲二对映异构体转化为相应的不对称螺环脲化合物,从而得到所需的光学异构体。因此获得的最终产品,如(4S)-(+)-6-氟-2,3-二氢-螺[4H-1-苯并吡喃-4,4'-咪唑烷]-2',5'-二酮(索必林)和(5'S)-3'-氯-5',6',7',8'-四氢-螺[咪唑烷-4,5'-喹啉]-2,5-二酮,已知在预防或缓解某些慢性糖尿病并发症方面具有用途。上述二对映异构脲中间体是新颖的化合物。