INDOLE 1,2,3,4-TETRAHYDROPYRIMIDINONE: SYNTHESIS, CHARACTERIZATION AND IT’S BIOLOGICAL APPLICATIONS

The present research work involves the use of exclusively and commercially available indole-3-carbaldehyde as a starting material to synthesize novel pyrimidine analogues. The synthesis of series of indole and pyrimidine containing N-substituted-4-(1H-indol-3-yl)-6-methyl-2-oxo-1, 2, 3, 4-tetrahydro-pyrimidine-5-carbohydrazide U(1-10) has been done by using principle of Biginelli condensation reaction.Indole-3-carbaldehyde was prepared by formylation of indole (Vilsmeier Haack reaction) using dimethylformamide and phosphorus oxychloride (1). The intermediate indole dihydropyrimidines was synthesized from a mixture of indole-3-carbaldehyde, urea and ethyl acetoacetate in the presence of zinc chloride as acid catalyst (2). The intermediate compound then refluxed with hydrazine hydrate by the addition of catalytic amount of conc. sulphuric acid, led to formation of parent compound 4-(1H-indol-3-yl)-6-methyl-2-oxo-1, 2, 3, 4-tetrahydropyrimidine-5-carbohydrazide(3). The parent compound 3 was used for synthesis of N’-substituted-4-(1H-indol-3-yl)-6-methyl-2-oxo- 1, 2, 3, 4-tetrahydropyrimidine-5-carbohydrazide and substituted aldehydes U (1-10), and/or Schiff bases of N’-substituted-4-(1H-indol- 3- yl)- 6- methyl- 2- oxo- 1, 2, 3, 4-tetrahydropyrimidine-5-carbohydrazide. Elemental analysis, FT-IR, ¹H-NMR, and Mass spectral data supports the structures of synthesized compounds. The selected synthesized compounds were screened for antibacterial and antifungal activities. Test compounds (U-5) and (U-7) were showed excellent antibacterial activity against all the bacterial strains. For antifungal activity, test compounds (U-5), (U-7), and (U-8) exhibited considerable activity compared to the standard compound.