| 摘要 |
<p>PURPOSE:To efficiently obtain a large amount of a new optically active 3,5-anti- dihydroxycarboxylic acid ester derivative having an extremely application range as an intermediate for physiologically active substance such as compacting relative compound useful as an treating agent for hyperlipemia and an intermediate for functional substance. CONSTITUTION:OH of an optical activator shown by formula I (R<1> and R<2> are alkyl, alkenyl, alkynyl, aryl or aralkyl; * is asymmetric carbon) is protected by a conventional procedure, the activator is hydrolyzed under a basic condition to readily give an optical activator shown by formula VI (R<5> is protecting group). Then this compound shown by formula VI is reacted with N,N'- carbonylimidazole to give an imidazolite, which is reacted with magnesium malonate to give an optical activator shown by formula VII (R<4> is in group in R<1> and R<2>) in high yield. Then the OH protecting group is deprotected and the resulting substance is highly stereo-selectively reduced by using a reducing agent to give an optical activator shown by formula I-1. Further, the compound shown by formula I-1 is reacted with 2,2-dimethoxypropane to readily give an optical activator shown by formula I-2.</p> |
