Novel compounds useful in the preparation of enantiomerically-pure 3-methyl-5-(1-(C.sub.1 -C.sub.3 -alkyl)-2-pyrrolidinyl)isoxazole in high yield, namely 5(S)-(3-methyl-5-isoxazolyl)-2-pyrrolidinone, 3-methyl-5-(1-methyl-2-pyrrolidinyl)-5-hydroxy-4,5-dihydro-isoxazole, and 1-(1-methyl-2(S)-pyrrolidinyl)-1,3-butanedione-3-oxime.
新化合物可用于高产得对映纯的3-甲基-5-(1-(C.sub.1-C.sub.3-烷基)-2-
吡咯烷基)
异噁唑,即5(S)-(3-甲基-5-
异噁唑基)-
2-吡咯烷酮,3-甲基-5-(1-甲基-2-
吡咯烷基)-5-羟基-4,5-二氢
异噁唑和1-(1-甲基-2(S)-
吡咯烷基)-1,3-
丁二酮-3-
肟。