A new procedure for the synthesis of 4H??pyrazolo [1, 5??c][1, 3, 5] thiadiazine??4??thiones

CB Vicentini, AC Veronese, M Guarneri…

Index: Vicentini; Veronese; Guarneri; Manfrini; Giori; Guccione Journal of Heterocyclic Chemistry, 1994 , vol. 31, # 6 p. 1477 - 1480

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Citation Number: 10

Abstract

Abstract Thiation of N-(1-tert-butyl-3-methylpyrazol-5-yl) carboxamides 2 with the Lawesson reagent afforded the corresponding thiocarboxamides 3. Heating of 3 in formic acid gave the N-dealkylated thiocarboxamides 4 which were cyclized into 4H-pyrazolo [1, 5-c][1, 3, 5] thiadiazine-4-thiones 5 by treatment with thiophosgene.