Srikanth Lingala

Pyrimidine is a synthetic heterocyclic aromatic organic compound similar to pyridine and benzene, with two nitrogen atoms at positions 1 and 3 of the six membered ring. It shows isomerisation with two other forms of diazine. Aldehydes undergo cyclocondensation reaction with thiourea and ethyl acetoacetate in presence of Aluminium chloride and Conc. HCl in methanol. On cooling the solid separated was filtered and was washed with cold methanol, dried and recrystallized from methanol. Various substituted pyrimidines were synthesized using different aldehydes. Purity and the homogeneity of all the title compounds were confirmed by their sharp melting points and TLC. The newly synthesized compounds were subjected to physico-chemical and elemental analysis. The structure of all the newly synthesized compounds was confirmed by IR, 1H NMR and Mass Spectral data. The data of antibacterial activity against S. aureus, E. coli, B. subtilis and S. epidermidis was tested and Antifungal activity against A. niger, P. chrysogenum and A. flavus and zone of inhibition was recorded. Aldehydes with electron releasing groups (IId, IIg) have shown much better antibacterial activity and compounds IIc and IIf have shown better anti fungal activity than the other derivatives.

The resistance to anthelmintic drugs has created a major hitch throughout the world over the decades. As per the WHO only a few drugs are used as anthelmintic agents in the recent days for human beings in the treatment of helminth infestations. An attempt has been made to synthesize some novel benzimidazole derivatives with N-methyl picolinamide moiety at 1H position of the benzimidazoles. And, some novel derivatives of 4-(2-substituted-1h-benzo[d]imidazol-1-yl)-n-methylpyridine-2-carboxamide have been synthesized as given in the scheme. All the newly synthesized final compounds and intermediates were purified and their IR, 1H NMR, and Mass spectral data have confirmed the chemical structures. All the newly synthesized molecules were examined for their anthelmintic activity against Indian adult earthworms (pheretima posthuma) at different concentrations (0.2% and 0.5%) and antibacterial activity against S.epidermidis, S.typhi, B.subtilis, B.cereus, P.aeruginosa and K.pneumoniae. Many of the newly synthesized molecules which were tested for the biological activity have shown promising activities when compared with that of the standard drugs.