Ethyl 1,8-napthyridin-2-one-3-carboxylate 1 on reaction with hydrazine hydr
ate furnishes 1,8-naphthyridin-2-one-3-carboxylic acid hydrazide 2, which o
n treatment with different aromatic aldehydes yields 1,8-naphthyridin-2-one
-3-carboxylic acid arylidene-hydrazides 3. Cyclocondensation of 3 with merc
aptoacetic acid in DMF in the presence of anhyd. ZnCl2 affords 2-aryl-3-(1,
8-naphthyridin-2-one-3-carbonylamino)-4-thiazolidinones 4. Structure elucid
ation of the products has been deduced on the basis of elemental analyses,
IR, H-1 NMR and MS data. Compounds 4 have been screened for their antibacte
rial activity against both grampositive and gram-negative bacteria.