The structure of 7,8-dimethoxy-3-oxo-3a,4,5,9b-tetrahydroisoquinolino-[1,2b]thiazolidine

The crystal structure of 7,8-dimethoxy-3-oxy-3a,4,5,9b-tetrahydroisoquinolino-[1,2b]thiazolidine has been investigated by X-ray diffraction methods. Crystals are monoclinic, space group P2-1/c, a=19.789(2), b=7.454(1), c=8.917 A, beta=100.43(1) degree, Z=4. The structure was solved by direct methods and refined to R=0.0329 for 2110 observed reflections. The sum of three bond angles around N atom is 359.3(3) degree, showing is near planar surrounding. The tetrahydroisoquinoline moiety is composed of the planar aromatic ring and hydrogenated heterocyclic ring having the conformation of non-ideal sofa. The next condensed heterocyclic five-membered ring accepts the form of envelope. This is the first published crystal structure of tetrahydroisoquinoline moiety fused with sulfur containing five-membered ring.