| 摘要 |
<p>PURPOSE:To obtain a succinic imide derivative having strong aldose reductase- inhibiting action, useful as an intermediate for a new tetrahydropyrrolo[1,2- a]pyrazine-4-spiro-3'-pyrrolidine derivative and its salt. CONSTITUTION:A succinic acid imide derivative of formula I (R is amino protected with a group eliminable by hydrolysis, t.-butoxycarbonylamino or pyrrol-l-yl; R<1> is protecting group of carboxyl) and its salts, e.g. 2- benzyloxycarbonylamino-2-ethoxycarbonylsuccinic acid imide. The compound of formula I is obtained as a compound of formula Ia by reacting, e.g. a compound of formula II (R<4> is a group eliminable by hydrolysis, e.g. t.- butoxycarbonyl) with a compound of formula III (R<5> is t.-butyl, etc.; Y is halogen) to afford a compound of formula IV and passing from the compound of formula IV through a compound of formula V and a compound of formula VI to obtain a compound of formula Ia. Then, the compound of formula Ia is passed through a compound of formula VII to provide a compound of formula Ib.</p> |
