10-Ethyl-10H-phenothia-zine-3-carbaldehyde.

In the title mol-ecule, C(15)H(13)NOS, the two benzene rings of the tricyclic fused-ring system are inclined at 21.1 (1)°. In the crystal, weak C-H⋯O hydrogen bonds link the mol-ecules into chains along [001]. The crystal packing also exhibits π-π inter-actions with a distance of 3.801 (5) Šbetween the centroids of the benzene rings of neighbouring mol-ecules.

2-(1H-Imidazol-1-yl)-4,6-dimethyl-pyrimidine.

The asymmetric unit of the title compound, C(9)H(10)N(4), consists of two mol-ecules in which the dihedral angles between the planes of the imidazole and pyrimidine rings are 4.8 (1) and 2.1 (1)°.