White, James D.; Kawasaki, Motoji, Journal of the American Chemical Society, 1990, vol. 112, # 12, p. 4991 - 4993
作者:White, James D.、Kawasaki, Motoji
DOI:——
日期:——
Total synthesis of (+)-latrunculin A, an ichthyotoxic metabolite of the sponge Latrunculia magnifica and its C-15 epimer
作者:James D. White、Motoji Kawasaki
DOI:10.1021/jo00046a008
日期:1992.9
Latrunculin A (1), an ichthyotoxic metabolite of the sponge Latrunculia magnifica with potent inhibitory action on microfilament-mediated processes involved in cell division, was synthesized via a convergent approach. Construction of a major segment of the latrunculin backbone was accomplished by means of a three-component coupling of aldehyde 24, beta-keto ester 27, and phosphonium salt 26, which established the conjugated EZ-diene moiety of 31. The thiazolidinone subunit of 1 was elaborated in the form of 39 from L-cysteine and was linked to 35 without nitrogen protection. Final lactonization of 47 was carried out using the Mitsunobu protocol. A parallel sequence employing the epimeric seco acid 48 produced 15-epilatrunculin A.
Synthesis of 1,3-dienes of (E,Z) configuration by a three-component coupling strategy
作者:James D. White、Mark S. Jensen
DOI:10.1016/0040-4020(95)00249-8
日期:1995.5
nucleophile, butadienyltriphenylphosphonium bromide, and an aldehyde gave conjugateddienes of predominantly (E,Z) configuration. Dianions of β-dicarbonyl systems and dicarboxylic acids, and monoanions of sulfones were employed as nucleophiles. Stereoselectivity in favor of an (E,Z)-1,3-diene was highest when a β-dicarbonyl dianion was used in conjunction with an α-branched aldehyde.