The synthesis and antimicrobial activity of 5-aroxy-2,6-dihydro-1H-pyrrolo[3,4-d] pyridazine-1-ones

Abstract

Aim. To develop an effective method for the synthesis of 5-aroxy-2,6-dihydro-1Н-pyrrolo[3,4-d]pyridazine-1-ones as promising objects to be investigated in the context of their antimicrobial activity. Results and discussion. It has been found that ethyl 4-formyl-5-chloro-1Н-pyrrole-3-carboxylates can be used as convenient source substrates for building 5-aroxy-2,6-dihydro-1Н-pyrrolo[3,4-d]pyridazine-1-one systems. MBsC (MFsC) and MBcC (MFcC) of the pyrrolo[3,4-d]pyridazine-1-ones synthesized were within the range of 31.25-125 μg/ml. Experimental part. The two-stage synthesis of 5-aroxy-2,6-dihydro-1Н-pyrrolo[3,4-d]pyridazine-1-ones was performed. The chemical composition and the structure of the compounds synthesized were confirmed by chromatography-mass spectra, IR- and NMR 1Н (13С) spectra. The screening of the antimicrobial activity using the micromethod of the double series dilutions in the liquid nutrient medium allowed identifying compounds with a moderate activity. Conclusions. A preparative convenient synthesis of 5-aroxy-2,6-dihydro-1Н-pyrrolo[3,4-d]pyridazine-1-ones has been developed. This method assumes the nucleophilic substitution of the chlorine atom in ethyl 4-formyl-5-chloro-1Н-pyrrole-3-carboxilates with an aroxyl fragment followed by the subsequent pyridazinoanelination of ethyl 5-aroxy-4-formyl-1Н-pyrrole-3-carboxylates by hydrazine hydrate. The results of the antimicrobial activity of the substances synthesized substantiate the feasibility of further in-depth studies in this area.

Keywords

• polyfunctional pyrroles
• hydrazine hydrate
• pyridazinoanelination
• antimicrobial activity
• pyrrolopyridazine