Reaction of 1,3-dimethyl-3a,9a-diphenyl-3,3a,9,9a-tetrahydroimidazo-[4,5-e]-1,3-thiazolo[3,2-b]-1,2,4-triazine-2,7(1H,6H)-dione with isatins

Condensation of 1,3-dimethyl-3a,9a-diphenyl-3,3a,9,9a-tetrahydroimidazo[4,5- e ]-1,3-thiazolo[3,2- b ]-1,2,4-triazine-2,7(1 H ,6 H )-dione with isatins afforded 6-(2-oxo-1,2-dihydro-3 H -indol-3-ylidene)-3,3a,9,9a-tetrahydro-1,3-dimethyl-3a,9a-diphenylimidazo-[4,5- e ]thiazolo[3,2- b ]-1,2,4-triazine-2,7(1 H ,6 H )-diones; a new conglomerate (space group P 2 1 2 1 2 1 ) was found by an X-ray diffraction study.