Synthesis, antimicrobial screeningand structure–activity relationshipof novel pyrimidines and their thioethers

In the present study, a series of novel pyrimidines (1) and their thioethers (2–5) were synthesized. Structures of the synthesized compounds were established by IR, ^1H NMR, ^13C NMR mass spectral data and elemental analysis. All the newly synthesized compounds were screened for their in vitro antibacterial and antifungal activities. Among the compounds tested, few were found to be most effective antibacterial and antifungal agents. The Structure–activity relationship studies revealed that thiazolopyrimidine derivatives carrying 3-nitrophenyl (4c) or 4-hydroxyphenyl (4b) group exhibited highest antibacterial activity, whereas dimethylated adduct carrying 3-nitrophenyl (2c) group exhibited highest antifungal activity. The results revealed that the synthesized compounds may be a potential lead for future drug discovery.