A Novel Benzamidazole Derivatives and synthesis thereof whereby novel benzimidazole derivatives are (R)-2-(4"-methoxyphenyl)-3-(3",5"-diflorophenyl)-1,2,3,5- tetrahydrobenzo[4,5]imidazo[1,2-c]pyrimidin-4-ol (KPB 13) and (R)-2-(4"-methoxyphenyl)-3-(2"-hydroxy,5"-methoxyphenyl)-1,2,3,5-tetrahydrobenzo[4,5]imidazo[1,2-c]pyrimidin-4-ol (KPB 15) having potent antitubercular activity. The said KPB 13 and KPB 15 have the structure shown below which are active against M. tuberculosis including drug-resistant mycobacteria and some non-tuberculosis mycobacteria.