Crystal structures of two ( Z )-2-(4-oxo-1,3-thia-zolidin-2-yl-idene)acetamides.

The crystal structures of two (oxo-thia-zolidin-2-yl-idene)acetamides, namely ( Z )-2-[2-(morpholin-4-yl)-2-oxo-ethyl-idene]thia-zolidin-4-one, C9 H12 N2 O3 S, (I), and ( Z )- N -(4-meth-oxy-phen-yl)-2-(4-oxo-thia-zolidin-2-yl-idene)acetamide, C12 H12 N2 O3 S, (II), are described and compared with a related structure. The Z conformation was observed for both the compounds. In (I), the morpholin-4-yl ring has a chair conformation and its mean plane is inclined to the thia-zolidine ring mean plane by 37.12 (12)°. In (II), the benzene ring is inclined to the mean plane of the thia-zolidine ring by 20.34 (14)°. In the crystal of (I), mol-ecules are linked by N-H⋯O hydrogen bonds, forming C (6) chains along the b -axis direction. The edge-to-edge arrangement of the mol-ecules results in short C-H⋯O and C-H⋯S inter-actions, which consolidate the chain into a ribbon-like structure. In the crystal of (II), two N-H⋯O hydrogen bonds result in the formation of C (8) chains along the b- axis direction and C (6) chains along the c -axis direction. The combination of these inter-actions leads to the formation of layers parallel to the bc plane, enclosing R 4 4 (28) rings involving four mol-ecules.