摘要:
Racemic 1-azaspiro[4.4]nonane-2,6-dione 1 was easily synthesized from cyclopentanone in five steps and resolved via chiral acetals into enantiomers. Cephlotaxine (-)-3 and its enantiomer (+)-3 were obtained from (-)-1 and (+)-1, respectively, according to the literature. (C) 1997 Published by Elsevier Science Ltd.