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

doi:10.1055/s-2008-1078208

LETTER

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;

Abstract

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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

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References

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.

16 For a representative example, see: Moore ML. Crossley FS. Org. Synth., Coll. Vol. III John Wiley and Sons; London: 1955. p.599