Synthesis and Antibacterial Activity Studies of the Conjugates of Curcumin with <i>closo</i>-Dodecaborate and Cobalt Bis(Dicarbollide) Boron Clusters

Abstract

A series of novel conjugates of cobalt bis(dicarbollide) and closo-dodecaborate with curcumin were synthesized by copper(I)-catalyzed azide-alkyne cycloaddition. These conjugates were tested for antibacterial activity. It was shown that all derivatives are active when exposed to Bacillus cereus ATCC 10702 and are not active against Gram-negative microorganisms and Candida albicans at the maximum studied concentration of 1000 mg/L. The conjugate of alkynyl-curcumin with azide synthesized from the tetrahydropyran derivative of cobalt bis(dicarbollide) exhibited activity against Gram-positive microorganisms: Staphylococcus aureus ATCC 29213, Enterococcus faecalis ATCC 29212 and the clinical isolate MRSA 17, that surpassed curcumin by 2–4 times.

Keywords

• polyhedral boron hydrides
• <i>closo</i>-dodecaborate
• cobalt bis(dicarbollide)
• curcumin
• “click” reaction
• antibacterial activity