New and facile method of preparation of the anti-HIV-1 agent, 1,3-dicaffeoylquinic acid

A facile and inexpensive preparation of 1,3-dicaffeoylquinic acid (cynarin) from the leaves Cynara cardunculus L. (Asteraceae) without the use of any chromatographic steps is described. The procedure is based on separation of the fraction rich in 1,5-dicaffeoylquinic acid, isomerisation of 1,5-dicaf feoylquinic acid to cynarin and, owing to its higher polarity, the simple i solation of cynarin from the reaction mixture. Cynarin inhibited HIV-1 repl ication in MT-2 cell culture at non-toxic concentrations similar to other p reviously tested dicaffeoylquinic acids, which have been recently establish ed as a potent and highly selective class of HIV-1 integrase inhibitors. (C ) 2001 Elsevier Science Ltd. All rights reserved.