Synthesis of some Mannich bases of 1-cyclohexylidene-N(1,2-dihydro-2-oxo-3H-indol-3-ylidene) thiosemicarbazones and their antibacterial activity.

Some Mannich bases of 1-cyclohexylidene-N(1,2-dihydro-2-oxo-3H-indol-3- ylidene) thiosemicarbazones have been prepared by employing formaldehyde and morpholine and piperidine as secondary amines. These Mannich bases have been characterised on the basis of different physico chemical evidences. Like some alkaloids, they also form reineckate complexes which serve for their estimation. Antibacterial activity of the synthesised Mannich bases has been studied by employing nine bacterial strains. Chloro group at position 5 broadened the spectrum of activity. Compounds with piperidine showed better activity than the compounds with morpholine, against almost all the organisms used (except 1 or 2 occasions).