Syntheses of doubly linked proanthocyanidins using free flavan units as nucleophiles: insight into the origin of the high regioselectivity of annulation
作者:Vipul V. Betkekar、Mio Harachi、Keisuke Suzuki、Ken Ohmori
DOI:10.1039/c9ob01896d
日期:——
method of doubly linked flavan dimers is reported via the acid-promoted annulationreaction using nascent catechins, (+)-catechin or (-)-epicatechin, as a dianionic partner and an ethylenedioxy-bridged flavan as a dicationic partner. Procyanidins A1 and A2 were synthesized. On the high regioselectivity of the annulationreactions, model experiments and computational studies were carried out.