Synthesis and Antimicrobial Activities of New Indolyl-Pyrimidine Derivatives

The purpose of research was to synthesize a series of new indolyl-pyrimidine-5- carbonitriles 2-5 from compound 1.The reaction of 2a with ethylcyanoacetate and aromatic aldehydes in presences of excess ammonium acetate gives 6 a-c while condensation with aromatic aldehydes produces chalcones 7a-c via the Claisen condensation .Structure of the synthesized compounds was confirmed by means of their IR,1H-NMR spectral data and elemental analysis .The antimicrobial testing of the synthesized compounds were evaluated. Some of the prepared compounds, 2-(1H-indol-3-yl)-4, 6-dioxo-6, 11-dihydro-4H-pyrimido [2, 1-b] quinazoline-3-carbonitrile 3 and 2-hydrazino-4-(1H-indol-3-yl)-6-oxo-1,6- dihydropyrimidine-5-carbonitrile 4 showed high antibacterial activity. Melting points of the synthesized compounds were determined by open end capillary tube method in Boetius melting point microscope and are uncorrected. The purity of the compounds was checked using precoated TLC plates (Merck 60 F254 ) using chloroform: methanol (3:1) solvent system. The structures of the compounds were characterized by Beckman Infrared Spectrophotometer PU9712 using KBr discs . The structures of the compounds were elucidated by 1H NMR (Proton Nuclear Magnetic Resonance) . The molecular weights of compound were determined by SSQ7000 mass spectrometer at 70 eV.1H NMR spectra were recorded on JoelEX270MHz spectrometer using TMS as internal standard. All the new compounds gave satisfactory analytical results (within 0.4 of the theoretical values). All the synthesized compounds (1-7) were purified by successive recrystallization . The purity of the synthesized compounds was checked by performing TLC. The structures of the synthesized compounds were determined on the basis of their FTIR and 1HNMR data. In accordance with the data obtained from antimicrobial activity, most of the synthesized compounds have shown moderate activity against the tested bacteria while compounds 2-(1H-indol-3-yl)-4, 6-dioxo-6, 11-dihydro-4H-pyrimido [2, 1-b]quinazoline-3-carbonitrile (3) and 2-hydrazino-4-(1H-indol- 3-yl)-6-oxo-1,6-dihydropyrimidine-5-carbonitrile (4) showed high antibacterial acivity. Only compounds 1,3,4,7a,7 b and 7c are active against C.albicans.