Synthesis and antifungal activity of 3-[2-substituted-5-oxo-3.5-dihydro-6.8-dicarbonitriles-1,2,4-triazolo [1,5-a] pyridin-7-y1] indole derivatives

ABSTRACT

Base catalyzed reaction of 1-substituted indole-3-carboxaldehydes 2a-d with malononitrile gave the corresponding 3-indolylidene malononitriles 3a-d. Heterocyclization of the latter compounds with 2-cyano-acetohydrazide, 2- acetyl-2-cyanoacetohydrazide and alpha-cyano acetyl arylaldehyde hydrazone derivatives gave the corresponding 1,6-diamino pyridine derivatives 4a-d, 3-[2-methyl-5-oxo-3,5-dihydro-6,8- dicarbonitriles-1,2,4-triazolo[1,5-a] pyridine-7-y1] indoles 5a-d and 3-[2-ary1-5-oxo-3,5-dihydro-6,8-dicarbonitriles-1,2,4-triazolo[1,5-a] pyridin-7-y1] indoles 6a-t, respectively. The target compounds 4a-d, 5a-d and 6a-t were evaluated in vitro against two strains of fungi, Candida albicans [AUCC-1720] and Aspergillus fumigatus [AUMC-1924], Fluconazole and Itraconazole were used as references. All compounds which contain the nitro group were found inefficient [MIC > 100 microg/mL], while the rest of the tested compounds exerted a slight activity [MIC 60-80 microg/mL] against each of C. albicans and A. fumigatus compared with the control