Vinyl and Alkynyl Pyrimidines as Michael Acceptors: An Approach to a Cylindrospermopsin Substructure
作者:Jane F. Djung、David J. Hart、Erick R. R. Young
DOI:10.1021/jo000504f
日期:2000.9.1
base-mediated intramolecular conjugate addition reactions in which a carbamate and a urea, respectively, behave as nitrogen nucleophiles. The cyclic carbamate derived from 9 was converted to 11 via a metalation-oxidation reaction in which 2-phenylsulfonyl-3-phenyloxaziridine behaves as a hydroxylation reagent. The cyclic urea derived from 24 was converted to cylindrospermopsin substructure 30 using dimethyldioxirane
乙烯基嘧啶9和炔基嘧啶24经历碱介导的分子内共轭加成反应,其中氨基甲酸酯和尿素分别充当氮亲核试剂。由9衍生的环状氨基甲酸酯通过金属氧化反应转化为11,其中2-苯基磺酰基-3-苯基恶唑烷充当羟基化试剂。使用二甲基二环氧乙烷引入C(7)羟基,将24衍生的环状脲转化为环精皮子亚结构30。