SYNTHESIS OF 11-BROMO-9-METHYL-6-METHYLENE-3-METHYLTHIO-5,6,9,10-TETRAHYDRO-8H-[1,2,4]TRIAZOLO[3',4':3,4]PYRAZINO[1,2-<i>c</i>]PYRIMIDINE-8,10-DIONE FROM 4-ALLYL-1-(3-METHYL-2,4-DIOXO-1,2,3,4-TETRAHYDRO-6-PYRIMIDINYLCARBONYL)THIOSEMICARBAZIDE

Abstract

4-Allyl-1-(3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinylcarbonyl)thiosemicarbazide is cyclized in alkaline medium into 4-allyl-3-(3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinyl)-1,2,4-triazoline-3-thione, which is converted on alkylation with iodomethane into the methylthio derivative. Reaction of the latter with bromine occurs with formation of 3-(5-bromo-3-methyl-2,4-dioxo-1,2,3,4-tetrahydro-6-pyrimidinyl)-4-(2,3-dibromopropyl)-5-methylthio-1,2,4-triazole, dehydrobromination of which with potassium carbonate leads to formation of the first representative of a new heterocyclic system, viz. 11-bromo-9-methyl-6-methylene-3-methylthio-5,6,9,10-tetrahydro-8H-[1,2,4]triazolo[3',4':3,4]pyrazino[1,2-c]pyrimidine-8,10-dione.

Authors: G. Myakushkene and P. Vainilavichyus.

English Translation in Chemistry of Heterocyclic Compounds, 1999, 35 (1), pp 64-67

http://link.springer.com/article/10.1007/BF02251663