127644-59-1Relevant articles and documents
Oligomeric Flavanoids. Part 9. The First Biflavanoids Based on Mopanol and Peltogynol as Inceptive Electrophiles
Malan, Johannes C. S.,Young, Desmond A.,Steynberg, Jan P.,Ferreira, Daneel
, p. 219 - 226 (2007/10/02)
Continued investigation of the phenolic metabolities of Colophospermum mopane reveals the occurence of the first series of biflavanoids based on mopanol and peltogynol as electrophilic species.Amongst these are the promopanidins, (+)-mopanane-(4β,6)-fisetinidols (5) and (7), the epimopanane-(4,6 and 4,8)-fisetinidols (9) and (11), and the unique oxidatively coupled epimopanone-guibourtinidol (13).They are accompanied by the related propeltogynidins, (+)-peltogynane-(4β,6)-fisetinidols (15) and (17), epipeltogynane-(4α,6)-(-)-fisetinidol (19), and (-)-fisetinidol-(4α,6')-(+)-peltogynol (21), the latter compound extending the rare series of biflavanoids with the equivalent of a 'terminal' flavan-3,4-diol moiety.The 2,3-cis-3,4-cis-(+)-mopanol (23) represents the first mopanoid/ peltogynoid with (2R,3R) configuration.The structures of the (+)-mopanane-(4β,6)-fisetinidols are confirmed by synthesis, the forcing conditions of which are explained in terms of the conformational rigidity of the mopanol c-ring.