A regioselective N1-alkylation of 3,4-dihydropyrimidin-2(1H)-ones using a very efficient mild base Cs(2)CO(3) and alkyl halides at room temperature has been reported. The selectivity of this methodology is excellent and the yields of the alkylated products are very good. Furthermore inhibitory action of both the 3,4-dihydropyrimidin-2(1H)-ones and the N1-alkylated derivatives were tested on Ca(2+)-ATPase, which revealed that the parent compounds can act as Ca(2+)-ATPase inhibitors whereas the N1-alkylated derivatives are inefficient for this purpose.