“…Alkylation of the selenium atom with various alkyl iodides was performed to give library 125 (Scheme 37).Compound 127 exhibited a marked cytotoxic effect on leukemia CCFF-CEM, colon HT-29, lung HTB-54, breast MCF-7 cell lines and replacement of the sulfur by a selenium atom 126 did not significantly affect biological activity[41]. An increase in Caspase-3 activity accompanied by cell cycle perturbation in a time-dependent manner was demonstrated with the hydroselenite salt 128 (Scheme 38)[42].Malhotra et al investigated the synthesis of 4-substituted 2-amino pyrido[3,4-d]pyrimidine derivatives 129 as potential anticancer agents. A tumor cell line screening was performed using the NCI 60 cancer cell lines panel, and showed inhibitory effects against the growth of the UO-31 renal cancer cell line, MDA-MB-468 and MCF-7 breast cancer cell lines (Scheme 39)[17].…”