The aim of this study was to synthesize the novel N-1 triazolyl and C-5 alkynylated pyrimidine and 7-deazapurine derivatives in order to evaluate their antitumor activities against human malignant tumor cell lines (Raji, K562, HeLa, CaCo-2). N-4-benzoyl-5-iodocytosine (1) was prepared by iodination reaction of N-4-benzoylcytosine which was then subjected to N-alkylation reaction with propargylbromide in the presence of NaH as base to give N-alkynylated cytosine derivative 2. N-1-triazolyl derivatives of N-4-benzoyl-5-iodocytosine (3–5) were obtained via copper catalysed „click“ reaction of N-1-propargylcytosine derivative 2 with corresponding azides. Sonogashira cross-coupling reaction of compounds 4 and 5 with corresponding terminal alkynes gave C-5 alkynylated derivates of N-4-benzoyl-N-1-triazolylcytosine 6 and 8. 7-deazapurine derivatives 7 and 9 were prepared by in situ 5-endo-dig cyclization of the compounds 6 and 8, respectively. The structures of newly synthesized compounds were determined by 1H NMR spectroscopy.