Synthesis and biological activity of 1,3,4-oxa(thia)diazole, 1,2,4-triazole-5-(thio)one and S-substituted derivatives of 3-((2-carboxyethyl)phenylamino)propanoic acid

A series of novel derivatives of 3-((2-carboxyethyl)phenylamino)propanoic acid bearing two identical substituted 1,3,4-oxadiazole, 1,3,4-thiadiazole, or 1,2,4-triazole moieties were synthesized and their molecular structures were confirmed by IR, H-1, C-13 NMR spectroscopy, and elemental analysis data. The synthesized compounds were screened for their reducing power, free radical scavenging, plant growth regulating, and antimicrobial properties. 5,5'-((Phenylazanediyl)bis(ethane-2,1-diyl))bis(4-phenyl-2,4-dihydro-3H-1,2,4-triazole-3-thione) showed excellent antioxidant activity, three times higher than that of the antibiotic control (cefazolin). 2,2'-((((Phenylazanediyl)bis(ethane-2,1-diyl))bis(4-phenyl-4H-1,2,4-triazole-5,3-diyl))bis(sulfanediyl))diacetate exhibited notable bactericidal activity against Pseudomonas aeruginosa with MBC and MIC values 7.3 A mu g/ml, whereas 12 compounds displayed significant fungicidal activity against Candida albicans with MIC value 3.9 A mu g/ml. Synthesis of compounds 2-27. R: 2, 5, 7, 10, 13, 15-27 C6H5-; 3, 8, 11 4-Cl-C6H4-; 4, 9, 12 CH3-; 6, 14 2.6-(CH3)(2)-C6H3-; R': 15 CH3CH2-; 16 (CH3)(2)CH-; 17 (CH3)(2)CHCH2-; 18 CH3CH2CH2CH2-; 19 (CH3)(2)CHCH2CH2-; 20 CH3CH2CH2CH2CH2-; 21 NH2COCH2-; 22 C6H5CH2-; 23 C6H5COCH2-; 24 4-ClC6H4COCH2-; 25 4-NO2C6H4COCH2-; 26 C2H5OCOCH2-.