Synthesis and Anti-Breast Cancer Potency of Mono- and Bis-(pyrazolyl[1,2,4]triazolo[3,4-][1,3,4]thiadiazine) Derivatives as EGFR/CDK-2 Target Inhibitors.

The target mono- and bis-(6-pyrazolyltriazolo-thiadiazine) derivatives and were synthesized using a straightforward protocol via reaction of 3-bromoacetylpyrazole with 4-amino--triazole-3-thiols and bis(4-amino-5-mercapto--triazol-3-yl)alkanes , respectively. The bis(6-pyrazolyl--triazolo[3,4-][1,3,4]thiadiazine) derivatives , and were also constructed by reaction of the triazolo[3,4-][1,3,4]thiadiazine-3-thiol with the proper dibromo compounds , and , respectively. Structures of the new substances were determined by spectroscopic and analytical data. Compounds , , and showed potent cytotoxicity against MCF-7 (IC = 3.16, 2.74, and 0.39 μM, respectively) and were safe against the MCF-10A cells. Compounds , , and also showed promising dual EGFR and CDK-2 inhibition activities, particularly was the most effective (IC = 19.6 and 87.9 nM, respectively), better than Erlotinib and Roscovitine. Compound treatment induced EGFR and CDK-2 enzyme inhibition by 97.18% and 94.11%, respectively, at 10 μM (the highest concentration). Compound notably induced cell apoptosis in MCF-7 cells, increasing the cell population by total apoptosis 43.3% compared to 1.29% for the untreated control group, increasing the cell population at the S-phase by 39.2% compared to 18.6% (control).