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Synlett 2008(16): 2421-2424  
DOI: 10.1055/s-2008-1078208
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

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

David V. Batchelor, David M. Beal, T. Bruce Brown, David Ellis, David W. Gordon, Patrick S. Johnson, Helen J. Mason, Michael J. Ralph, Toby J. Underwood, Simon Wheeler*
Sandwich Chemistry, Pfizer Global Research and Development, Ramsgate Road, Sandwich, Kent, CT13 9NJ, UK
Fax: +44(1304)651987; e-Mail: simon.wheeler@pfizer.com;
Further Information

Publication History

Received 1 May 2008
Publication Date:
22 August 2008 (online)

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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.