Chemical Conversion of Nocathiacin I to Nocathiacin II and a Lactone Analogue of Glycothiohexide α

Abstract

Nocathiacin I (1) was converted to its deoxy indole analogue, nocathiacin II (2), another natural product, by a unique and facile chemical process. This process was applied to nocathiacin IV (4), generating the lactone analogue of glycothiohexide α (5), which was also prepared from nocathiacin II by a mild hydrolytic process. In contrast to glycothiohexide α (3), this lactone analogue (5) was found to exhibit in vivo antibacterial efficacy in an animal (mouse) infection model.