Acid promoted intramolecular formation of 3,5-anhydro-1,4-furano-7-ulose derivatives via the Wittig-cyclization procedure and their antimicrobial properties

Abstract

We report a convenient method for the synthesis of 3,5-anhydrofuranose derivatives. Formation of the 3,5-anhydro (oxetane) rings was achieved by the Wittig-cyclization procedure under acid promoted conditions starting from 5(E)-eno-1,4-furano-7-ulose derivatives (1, 4, and 7). Unprotected hydroxyl groups on C-3 of the furanose rings added intramolecularly to the acyclic double bond under very mild acidic conditions in methanol to form the stereoisomeric 3,5-anhydro derivatives in good yields. The products (2, 3, 5, 6, and 8) were found to exhibit antibacterial properties. The reaction was found to be strongly solvent dependent as use of methanol instead of chloroform afforded 5-acetylmethyl-furfural 9 as a major product instead of the expected oxetane. All of the synthesized compounds were tested for antimicrobial activity against Staphylococcus aureus ATCC6538-P, Bacillus subtilis ATCC 6633, Salmonella typhimurium CCM 5445, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 12228, Pseudomonas aeruginosa ATCC 27853, Klebsiella pneumoniae CCM 2318, and Candida albicans ATCC 10239 and exhibited a range of activities against selected microorganisms.