Bio-active conjugates of curcumin having ester, peptide, thiol and disulfide links

Abstract

Mixed bioconjugates of curcumin [4,4’-di-O-(glycinoyl-cystinoyl) curcumin, 4,4’-di- O-(glycinoyl-cysteinoyl) curcumin, 4,4’-di-O-L-(alaninoyl) curcumin, 4,4’-di-(O- glycinoyl)—glycinoyl) curcumin and 4,4’-di-O{(3,4,5-O-acetyl) galloyl} curcumin] have been prepared and characterized. These bioconjugates contain biodegradable (ester and peptide) bonds and have been tested for antifungal and anti bacterial activities, which have been found to be considerably enhanced vis-à-vis curcumin. The plausible reasons for this remarkable enhancement in therapeutic activity may be due to better cellular uptake, increased cellular concentration, better receptor binding at the target sites due to extended conjugation. These conjugates may act as potent prodrugs since these can get enzymatically hydrolysed at the target sites.