isolated from the sea hare Aplysia kurodai together with the congeners aplyronines B (3) and C (4). The absolute stereostructure of aplyronine A (2) was determined by the instrumental analysis (mainly NMR and MS) and the enantioselectivesynthesis of the fragments obtained from chemical degradation of aplyronine A (2). The structures of aplyronines B (3) and C (4) were also elucidated. Cytotoxicity and
Synthesis of (3aR,8S,8bS,2′R)-(+)-sorgolactone and its stereoisomers, the germination stimulant from sorghum bicolor
作者:Kenji Mori、Junichi Matsui
DOI:10.1016/s0040-4039(97)10078-8
日期:1997.11
Methyl (S)-citronellate (2) was converted to (3aR,8S,8bS,2′R)-(+)-sorgolactone (1a) by employing the radical cyclization of 6 to 7 as the key-step. Three other stereoisomers (1b, 1c and 1d) of sorgolactone were also prepared. The CD spectrum of 1a was in accord with that reported for the natural product.