In this study, a series of new adenine derivatives possessing 1,3,4-oxadiazole moiety with different S-alkyl group were synthesized. The structures of these compounds were established on the basis of FT-IR, H-1, C-13-APT NMR, and HRLC-MS spectral data. Their DNA binding abilities were investigated in vitro by agarose gel electrophoresis. The relationship between the structure and the mentioned biological activities was discussed. The results showed that these compounds 5d and 5c exhibited DNA cleavage activity. Compounds DNA interaction studies reveal that compounds have affinity towards A/A and G/G nucleotides on DNA. None of the compounds at 2500 A mu M concentration have no inhibitory effect on microbial growth of tested strain of bacteria and yeast strain used in this study.