Synthesis, in vitro anticancer and antimicrobial evaluation of novel substituted dihydropyrimidines

A series of 1,4-dihydropyrimidine derivatives 3(a-t) were prepared from Biginelli reactions by using ethyl acetoacetate, substituted benzaldehyde and thiourea in the presence of piperidine and ethanol. The compounds 3(a-t) were reacted with dimethylsulphate, diethylsulphate, butyl bromide and benzyl chloride to give the new series of compounds 4(a-t). The structures of the newly synthesized compounds 4(a-t) were established by IR, (1) H NMR, Mass spectra and elemental analysis. The synthesized compounds were evaluated for their in vitro anticancer activity by using Sulforhodamine B assay method against the growth of four humans cancer cell lines, antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and for antifungal activity against Candida albicans and Aspergillus niger. The compounds exhibited good anticancer activity and moderate antibacterial and antifungal activities. Compounds 4b, 4c, 4d, 4g, 4i, 4n, 4o, 4q and 4s showed significant anticancer activity when compared with the doxorubicin as a standard reference drug.