The Synthesis of Triazolothiadiazines and Thiadiazoles From 1,2-Bis-(4-amino-5-mercapto-1,2,4-triazol-3-yl)- Ethanol and Ethane

Abstract

The reaction of DL-malic and succinic acids with thiocarbohydrazide afforded 1,2-bis[4-amino-5-mercapto-1,2,4-triazol-3-yl]-ethane derivatives 3a and 3b. The reaction of 3a,b with phenacyl bromide and benzoin afforded 1,2-bis-1,2,4-triazolo [3,4-b][1,3,4]thiadiazine derivatives 4 and 5. The carboethoxymethylation of 3a and 3b gave 6a and 6b, respectively, and their reactions with carbon disulfide and benzoylisothiocyanate gave the 1,2-bis-1,2,4-triazolo[3,4-b][1,3,4]thiadiazole 7 and 9, and with p-nitrobenzaldehyde gave a Schiff's base and dihydrothiadiazole 8. The structures were confirmed by using ¹ H and ¹³ C NMR spectra. Selected members of these compounds were screened for antimicrobial activity.

Keywords:

• 1,2,4-triazole
• antimicrobial activity
• Malic acid
• seco C-nucleosides
• succinic acid
• triazolo[3,4-b][1,3,4]thiadiazine
• triazolo[3,4-b][1,3,4]thiadiazole

Acknowledgments

We gratefully to Dr. Hasan Abd El-Salam, Assistant Prof. of Microbiology, Faculty of Pharmacy, Zagazig University, Zagazig, Egypt, for performance of the biological assay. We also gratefully for Konstanz University, Germany, for carring out all spectra and micro analysis.