Buy article online - an online subscription or single-article purchase is required to access this article.
organic compounds
The structures of two 1,2,4-triazole derivatives, namely 5-(4-chlorophenyl)amino-8,9,10,11-tetrahydro[1]benzothieno[3,2-e] [1,2,4]triazolo[1,5-c]pyrimidine, C17H14ClN5S, and its 2-methyl derivative, C18H16ClN5S, have been determined. The cyclohexene ring in each compound shows disorder. Both molecules are nearly planar, with the chlorophenyl rings lying almost in the same plane as the rest of the structure. Both crystals are stabilized by N-HN hydrogen bonds.