N-[Coumarin-6/-yl]carbamic acid hydrazide 2a-c on condensation with isatin yields indole-2-oxo-3-(2/ -oxo-2/H-benzopyran-6/-yl-semicarbazone 3a-c. Compound 3a-c on treatment with thiaglycollic acid in dry 1,4-dioxane in presence of catalytic amount of anhydrous ZnCl2 affords 3-(2/-oxo-2/H-benzopyran-6/-yl)-spiro-3H-[indole-(1H,2H)- 3,2-(4H)-thiazolidin-1-yl]-2,4-dioxo-urea 4a-c, compound 3a-c were also treated with chloroacetyl chloride to afford 3- (2/-oxo-2/H-benzopyran-6/-yl)-spiro-3H-[indole-(1H,2H)-3-chloro-2,4-dioxo-azetidin-1-yl]-urea. 5a-c. All the newly synthesized compounds have been confirmed on the basis of their spectral and analytical data. The synthesized compounds 3a-c, 4a-c and 5a-c were screened for the antibacterial activities against Gram positive and Gram negative bacteria and have been found to exhibit significant antibacterial activities.

N-[Coumarin-6/-yl]carbamic acid hydrazide 2a-c on condensation with isatin yields indole-2-oxo-3-(2/ -oxo-2/H-benzopyran-6/-yl-semicarbazone 3a-c. Compound 3a-c on treatment with thiaglycollic acid in dry 1,4-dioxane in presence of catalytic amount of anhydrous ZnCl2 affords 3-(2/-oxo-2/H-benzopyran-6/-yl)-spiro-3H-[indole-(1H,2H)- 3,2-(4H)-thiazolidin-1-yl]-2,4-dioxo-urea 4a-c, compound 3a-c were also treated with chloroacetyl chloride to afford 3- (2/-oxo-2/H-benzopyran-6/-yl)-spiro-3H-[indole-(1H,2H)-3-chloro-2,4-dioxo-azetidin-1-yl]-urea. 5a-c. All the newly synthesized compounds have been confirmed on the basis of their spectral and analytical data. The synthesized compounds 3a-c, 4a-c and 5a-c were screened for the antibacterial activities against Gram positive and Gram negative bacteria and have been found to exhibit significant antibacterial activities.