thiazine

Any of a class of organic chemical compounds containing an aromatic ring containing one sulfur atom, one nitrogen atom, and four carbon atoms. Thiazines are often used in making dyes, drugs, and insecticides.

A six-membered heterocycle containing four carbon atoms, one nitrogen and one sulfur atom, and two double bonds; many of its derivatives have important applications

a compound made up of a ring of four carbon atoms and one sulfur atom and one nitrogen atom