(2E)-2-(2,4-Dichloro-phenyl-sulfon-yl)-3-(4-methyl-anilino)-3-(methyl-sulfan-yl)acrylonitrile.

The title compound, C(17)H(14)Cl(2)N(2)O(2)S(2), and the 3-methoxy-anilino analogue reported in the preceding paper have been used as starting materials to develop benzothia-zine derivatives with anti-malarial activity. The mol-ecule displays an E (trans) configuration about the central double bond. Due to conjugation in the C=C-C N group, the putative single bond shows a significant shortening [1.418 (3) Å]. The mol-ecule has a six-membered ring involving an intra-molecular N-H⋯O(sulfon-yl) bond, which is an example of resonance-assisted hydrogen bonding. In the crystal structure, bonds of the C-H⋯O(sulfon-yl) and C-H⋯N(cyano) types form double layers of mol-ecules parallel to (01). Within these layers there are π-π inter-actions between benzene rings of pairs of centrosymmetrically related mol-ecules, with distances of 3.7969 (12) Å between centroids. C-H⋯π interactions are also present.