γ-oxo carboxylic acids in heterocyclic synthesis -: IV.: Synthesis of some pyridazines containing phthalyl and tosyl amino acids using dcc as the condensing agent

The 3(2H)-oxo-, 3(2H)-thioxo- or 3-amino-pyridazine derivatives 4, 6 and 7 were coupled with N-phthalyl- or N-tosyl-amino acids in one-step using N,N'-dicyclohexyl-carbodiimide as the condensing agent to furnish the corresponding 3-(N-phthalyl- or N-tosyl-aminoacyl)pyridazine derivatives 8-10 respectively. Hydrazinolysis of the N-phthalyl derivatives in methanol yielded the corresponding unprotected derivatives 11-13. The antibacterial activities of the prepared compounds were tested.