In the title compound, C17H10ClN3OS, the fused thiazolo[3,2-b]-1,2,4-triazo
le system is almost planar. The phenyl substituents are planar within exper
imental error and make dihedral angles of 16.5 (1) and 10.9(1)degrees with
the thiazolo-triazole system. There are three intramolecular hydrogen-bond
interactions of types C-H ... N, C-H ... O and C-H ... S.