3-(Benzothia-zol-2-yl)-3-(prop-2-yn-yl)hex-5-yn-2-one.

The title compound, C(16)H(13)NOS, was prepared by alkyl-ation of 1-(benzothia-zol-2-yl)propan-2-one with propargyl bromide. The asymmetric unit contains two mol-ecules that are crystallographically independent but linked to each other by non-classical C-H⋯O hydrogen bonds, building up a dimeric substructure. The benzothia-zole rings are essentially planar with maximum deviations of 0.

Dimethyl 3-acetyl-3-(1,3-benzothia-zol-2-yl)penta-nedioate.

The title compound, C(16)H(17)NO(5)S, was one of two condensation products from the reaction of 1-(1,3-benzothia-zol-2-yl)propan-2-one with methyl chloro-acetate. The non-H atoms in each of the four substituent groups on the central quaternary C atom are virtually coplanar. The maximum deviations from the least-squares planes are 0.