申请人:Takeda Chemical Industries, Ltd.
公开号:US06002011A1
公开(公告)日:1999-12-14
A substantially solvent-free and stable crystal of the compound of the formula: ##STR1## wherein the ring A may optionally be substituted, R.sup.1 represents hydrogen or an N-protecting group, each of R.sup.2, R.sup.3 and R.sup.4 (1) a hydrogen atom, (2) an alkyl group which may optionally be substituted with halogen atom(s) or (3) an alkoxy group which may optionally be substituted with halogen atom(s) or alkoxy; or its salt, is produced by subjecting a solvate of the compound (I) or its salt to de-solvent treatment, in an industrially advantageous method.
化合物的结晶体,其化学式为:##STR1##其中环A可以选择性地被取代,R.sup.1代表氢或N-保护基团,R.sup.2、R.sup.3和R.sup.4中的每一个(1)是氢原子,(2)是烷基基团,该基团可以选择性地被卤原子取代,或(3)是烷氧基团,该基团可以选择性地被卤原子或烷氧基团取代;或其盐,通过将化合物(I)的溶剂合物或其盐经受脱溶剂处理而制得,这是一种在工业上具有优势的方法。