Synthesis and Biological Activity of 4-(4-Hydroxybenzylidene)-2- (substituted styryl) oxazol-5-ones and Their o-glucosides

The 4-(4-hydroxybenzylidene)-2-methyl oxazol-5-ones 1 were treated with various aldehydes in the presence of acetic acid to form 4-(4-hydroxybenzylidene)-2-(substituted styryl) oxazol-5-ones 2a-i, which were glucosylated using α-acetobromoglucose as a glucosyl donor to afford 4-(4-o-β-d-tetra-o-acetyl-glucoxybenzylidene)-2- (substituted styryl) oxazol-5-ones 3a-i, which were deacetylated using zinc acetate in absolute methanol to form 4-(4-o-β-d-glucoxybenzylidene)- 2-(substituted styryl) oxazol-5-ones 4a-i. The compounds showed good antimicrobial and antifungal activity.