title: Formal syntheses of (+/-)-stemonamine and (+/-)-cephalotaxine.
abstract: A short and efficient approach to aza-quaternary pyrrolo[1,2-a]azepine 8 and aza-quaternary indolizine 23, as the crucial intermediates for syntheses of stemonamine (1a) and cephalotaxine (1b), has been developed on the basis of the key intramolecular Schmidt reaction of symmetric azido-diones 5 and 18, respectively.
authors.affiliation: State Key Laboratory of Applied Organic Chemistry and Department of Chemistry, Lanzhou University, Lanzhou 730000, PR China.
authors.forename: Yu-Ming
authors.initials: YM
authors.lastname: Zhao
authors.forename: Peiming
authors.initials: P
authors.lastname: Gu
authors.forename: Hai-Jun
authors.initials: HJ
authors.lastname: Zhang
authors.forename: Qing-Wei
authors.initials: QW
authors.lastname: Zhang
authors.forename: Chun-An
authors.initials: CA
authors.lastname: Fan
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: Tu
authors.forename: Fu-Min
authors.initials: FM
authors.lastname: Zhang