Crystal structure of 4-(benzo[ d ]thia-zol-2-yl)-1,2-dimethyl-1 H -pyrazol-3(2 H )-one.

In the title compound, C 12 H 11 N 3 OS, the inter-planar angle between the pyrazole and benzo-thia-zole rings is 3.31 (7)°. In the three-dimensional mol-ecular packing, the carbonyl oxygen acts as acceptor to four C-H donors (with one H⋯O as short as 2.25 Å), while one methyl hydrogen is part of the three-centre system H⋯(S, O). A double layer structure parallel to (01) can be recognized as a subsection of the packing.