Total synthesis of the 5-epimers of naturally occurring (−)-hyacinthacine A5 and unnatural (+)-hyacinthacine A4
作者:Isidoro Izquierdo、María T. Plaza、Juan A. Tamayo、Fernando Sánchez-Cantalejo
DOI:10.1016/j.tetasy.2007.09.014
日期:2007.9
(1R,2S,3R,5S,7aR)-1,2-Dihydroxy-3-hydroxymethyl-5-methylpyrrolizidine 10 [(+)-5-epihyacinthacine A5] and (1R,2S,3R,5S,7aS)-1,2-dihydroxy-3-hydroxymethyl-5-methylpyrrolizidine 17 [ent-5-epihyacinthacine A4] have been synthesized by either Horner–Wadsworth–Emmons (HWE) or Wittig methodology using aldehydes 6 and 13, prepared from (2R,3S,4R,5R)-3,4-dibenzyloxy-N-benzyloxycarbonyl-2′-O-tert-butyldiphenylsilyl-2
(1 R,2 S,3 R,5 S,7a R)-1,2-二羟基-3-羟甲基-5-甲基吡咯烷核苷10 [(+)-5- Epi hyacinthacine A 5 ]和(1 R,2 S,3 R,5 S,7a S)-1,2-二羟基-3-羟甲基-5-甲基吡咯烷嗪17 [ ent --5- epi hyacinthacine A 4 ]由Horner-Wadsworth-Emmons(HWE)或Wittig合成使用方法的醛6和13,从(2制备ř,3小号,4 - [R,5 - [R)-3,4- dibenzyloxy- ñ -苄氧羰基-2' - ö -叔-butyldiphenylsilyl -2,5-双(羟甲基)吡咯烷5(部分保护DALDP)和(2 - [R ,3小号,4 - [R,5小号)-3,4- dibenzyloxy- ñ -苄氧羰基-2,5-双(羟甲基)-2' - Ô -pivaloylpyrrolidine