Synthesis of 3, 4-dihydropyrimidin-2(1H)-one derivatives and evaluation of their antibacterial activity.

In medicinal chemistry, nitrogen atom containing molecules have gained a lot of attention as they possess diverse biological properties. Dihydropyrimidinone is one such pharmacologically important molecule possessing several properties such as anti-bacterial, anti-fungal, anti-inflammatory, anti-oxidant, antipyretic, anti-depressant, anti-tumor etc. A series of substituted dihydropyrimidinone derivatives have been synthesized via classical Biginelli condensation reaction using 4-fluorobenzaldehyde, urea and ethyl acetoacetate with chloroacetic acid as catalyst. The formed dihydropyrimidinone esters were subjected to oxidation using 60% nitric acid. These oxidized esters were then chlorinated using POCl3 via functional group conversion of C=O to C-Cl on the dihydropyrimidinone moiety. Later, different amino acids and amine groups were fused to the chloro substituted pyrimidine using potassium carbonate as base and DMF as the solvent to synthesis a series of eight novel derivatives. The compounds were obtained with good yield and were structurally characterized using 1H NMR and LC-MS. The synthesized compounds were evaluated for their antibacterial activity against Staphylococcus aureus (Gram positive bacteria) and Escherichia coli (Gram negative bacteria) using Agar Well Diffusion method. [ABSTRACT FROM AUTHOR]