In the present work a new and versatile route for synthesis of fused heterocycles (furo-pyrrolo-pyrido pyrimidine derivatives) using 1, 3 dipolar cycloaddition has been described. The structures of the synthesized compounds were analyzed by IR and 1H NMR and were purified by recrystallization and column chromatography. In-silico molecular docking studies were carried out to analyse the binding affinity of the pyrimidine derivatives towards thymidylate synthase. The synthesized compounds possess good binding interactions with thylidylate synthase showing a docking score of -7.0 for compound 4 and -8.7 for compound 6 which is greater when compared to standards 5-fluoro uracil (-5.0) and Methotrexate (-8.6). The results demonstrate a simple, mild and efficient method for the synthesis of novel compound (furo-pyrrolo-pyrido-pyrimidine derivative 6) and their potential anticancer property as thymidylate synthase inhibitor.