The Structure and Reactions of Gossypol. IV. The Synthesis of Desapogossypol Hexamethyl Ether^1,2

Diastereofacial selectivity in the reaction of allylic organometallic compounds with imines. Stereoelectronic effect of imine group

“…The erythro selectivity of crotyl-9-BBN (entries 9-12), as well as crotyllithium and crotylmagnesium chloride (entries 1, 2, 5, and 8), can be explained via the six-mem- (8) Yamamoto, Y.; Yatagai, H.; Naruta, Y.; Maruyama, K. J. Am.…”

Gossypol, a Pigment of Cottonseed.

“…Because of the dissimilarities, they concluded that there was reason to question the structure postulated for desapogossypol hexamethyl ether (19). Later, however, Shirley (211) synthesized the compound having the structure proposed by Adams, Morris, Geissman, Butterbaugh, and Kirkpatrick (19) and found it to be identical with the compound prepared from gossypol.…”

Evidence for a Trianion Intermediate in the Metalation of 4-Hydroxy-6,7-dimethoxy-8-methyl-2-naphthoic Acid. Methodology and Application to Racemic 5,5′-Didesisopropyl-5,5′-dialkylapogossypol Derivatives

“…A formal racemic synthesis was reported by Edwards and Cashaw in 1956 . In the course of their synthesis of desapogossypol hexamethyl ether, Shirley reported an organolithium−CoBr 2 oxidative coupling that proceeded in poor yield (25%) . The first asymmetric total synthesis of ( S )-(+)-gossypol was described by Meyers using chiral oxazolines as the naphthyl substituent via an asymmetric Ullmann coupling …”