A Convenient Synthesis of Highly Substituted 3-N,N-Dialkylamino-1,2,4-triazoles

Abstract

The title compounds are prepared from S-methylisothioureas and acyl hydrazides in moderate to good yields. The reaction is characterized by relatively mild conditions and very broad functional group tolerance.

Key words

heterocycles - cyclisations - sulfur - medicinal chemistry - drugs

References and Notes

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15

This avoided the use of the carcinogenic MeI and gave the S-methylisothiourea as the free base rather than the HI salt thereby allowing for simpler assessment of the role of acid in the cyclisation reaction.