Synthesis and fungicidal activity of dehydroabietyl-1,2,4-triazolo-thiazolidinones

In search of novel potent bioactive compounds, a series of novel dehydroabietic acid derivatives bearing 1,2,4-triazolo-thiazolidinone moieties were designed and synthesized. Seven compounds were synthesized of the type 6-substituted benzylidene-3-dehydroabietyl-thiazolo[2,3-c][1,2,4]triazol-5-ones. To this purpose a condensation reaction was performed with 3-dehydroabietyl-thiazolo[2,3-c][1,2,4]triazol-5-one and various aromatic aldehydes. All the title compounds were analyzed and characterized by means of IR, MS, 1 H NMR, 13 C NMR, and elemental analysis. A preliminary bioassay showed that, at a concentration of 50 μg ml -1 , the target compounds exhibited the best fungicidal activity against Fusarium graminearum ( F. graminearum ) of the five fungi tested ( F. oxysporum f . cucumerinum, Alternaria solani, Physalospora piricola, Cercospora arachidicola , and F. graminearum ).