Synthesis, Crystal Structure, and Biological Activity of 4-Methyl-1,2,3-thiadiazole-Containing 1,2,4-Triazolo[3,4-b][1,3,4]thiadiazoles
Heterocyclic compounds play an important role as the main sources of lead molecules of agrochemicals. Synthesis and biological activity of thiadiazole-containing 1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles were seldom reported. To find novel lead compounds with various biological activities, a series...
Saved in:
Published in | Journal of agricultural and food chemistry Vol. 58; no. 5; pp. 2630 - 2636 |
---|---|
Main Authors | , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
WASHINGTON
American Chemical Society
10.03.2010
Amer Chemical Soc |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Heterocyclic compounds play an important role as the main sources of lead molecules of agrochemicals. Synthesis and biological activity of thiadiazole-containing 1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles were seldom reported. To find novel lead compounds with various biological activities, a series of 6-substituted-3-(4-methyl-1,2,3-thiadiazolyl)[1,2,4]triazolo[3,4-b][1,3,4]thiadizoles were rationally designed and synthesized according to the principle of combinations of bioactive substructures by the condensation of 3-(4-methyl-1,2,3-thiadiazolyl)-4-amino-1,2,4-triazole-5-thione with various carboxylic acids and phosphorus oxychloride. All newly synthesized compounds were identified by proton nuclear magnetic resonance (1H NMR), infrared spectroscopy (IR), electroionization mass spectrometry (EI/MS), and elementary analysis. The crystal structure of 3-(4-methyl-1,2,3-thiadiazolyl)-6-(4-methylphenyl)[1,2,4]triazolo[3,4-b][1,3,4]thiadizole was determined by X-ray diffraction crystallography. In this crystal, two intermolecular hydrogen bonds (N2···H−C12 and N3···H−C13), a weak intermolecular interaction (S···S), and the weak pπ−pπ intermolecular interaction were observed. Fungicide screening indicated that all of the target compounds showed certain extent of growth inhibition against fungi tested. 3-(4-Methyl-1,2,3-thiadiazolyl)-6-n-propyl[1,2,4]triazolo[3,4-b][1,3,4]thiadizole and 3-(4-methyl-1,2,3-thiadiazolyl)-6-trichloromethyl[1,2,4]triazolo[3,4-b][1,3,4]thiadizole were found to have potential wide spectrum of fungicide activity. The median effective concentrations (EC50) detected for 3-(4-methyl-1,2,3-thiadiazolyl)-6-trichloromethyl[1,2,4]triazolo[3,4-b][1,3,4]thiadizole to six fungi were from 7.28 μmol/L against Pellicularia sasakii (Shirai) to 42.49 μmol/L against Alternaria solani. The results indicated that thiadiazole-containing 1,2,4-triazolo[3,4-b][1,3,4]-thiadiazoles were potential fungicide lead compounds. |
---|---|
Bibliography: | http://dx.doi.org/10.1021/jf9029628 ObjectType-Article-1 SourceType-Scholarly Journals-1 ObjectType-Feature-2 content type line 23 |
ISSN: | 0021-8561 1520-5118 |
DOI: | 10.1021/jf9029628 |