Optically active (C.sub.1 -C.sub.3) alkyl 2R-chroman-2-carboxylates are prepared by partial hydrolysis of the corresponding racemic ester using a microbial lipase as catalyst. Said 2R-chromancarboxylate is converted via novel 2R-(hydroxymethyl) chroman, 2R-(trifluoromethylsulfonyloxymethyl) chroman and 2R-benzylchroman intermediates into 2R-benzylchroman-6-carbaldehyde, a compound of known utility in the manufacture of certain hypoglycemic agents.
通过使用微
生物脂肪酶作为催化剂,通过对应的外消旋酯的部分
水解制备具有光学活性的(C.sub.1 -C.sub.3)烷基2R-色甘-2-
羧酸酯。所述的2R-
色甘酸酯经过新型的2R-(羟甲基)色甘、2R-(三
氟甲磺氧甲基)色甘和2R-苄基色甘中间体转化为2R-苄基色甘-6-羰基,这是一种已知在制造某些降血糖剂中具有实用价值的化合物。