A DFT and semiempirical model-based study of opioid receptor affinity and selectivity in a group of molecules with a morphine structural core

6-Bromo quinazoline derivatives as cytotoxic agents: design, synthesis, molecular docking and MD simulation

Based on unselectively, several side effects and drug resistance of available anticancer agents, the development and research for novel anticancer agents is necessary. In this study, a new series of quinazoline-4(3H)-one derivatives having a thiol group at position 2 of the quinazoline ring (8a-8 h) were designed and synthesized as potential anticancer agents. The Chemical structures of all compounds were characterized by 1H-NMR, 13C-NMR, and Mass spectroscopy. The antiproliferative activity of all derivatives were determined against two cancer cell lines (MCF-7 and SW480) and one normal cell lines (MRC-5) by the MTT method. Cisplatin, Erlotinib and Doxorubicin were used as positive controls. The results of in vitro screening showed that 8a with an aliphatic linker to SH group was the most potent compound with IC50 values of 15.85 ± 3.32 and 17.85 ± 0.92 µM against MCF-7 and SW480 cell lines, respectively. 8a indicated significantly better potency compared to Erlotinib in the MCF-7 cell line. The cytotoxic results obtained from testing compound 8a on the normal cell line, revealing an IC50 value of 84.20 ± 1.72 µM, provide compelling evidence of its selectivity in distinguishing between tumorigenic and non-tumorigenic cell lines. Structure-activity relationship indicated that the variation in the anticancer activities of quinazoline-4(3H)-one derivatives was affected by different substitutions on the SH position. Molecular docking and MD simulation were carried out for consideration of the binding affinity of compounds against EGFR and EGFR-mutated. The binding energy of compounds 8a and 8c were calculated at -6.7 and - 5.3 kcal.mol- 1, respectively. Compounds 8a and 8c were found to establish hydrogen bonds and some other important interactions with key residue. The DFT analysis was also performed at the B3LYP/6-31 + G(d, p) level for compounds 8a, 8c and Erlotinib. Compound 8a was thermodynamically more stable than 8c. Also, the calculated theoretical and experimental data for the IR spectrum were in agreement. The obtained results delineated that the 8a can be considered an appropriate pharmacophore to develop as an anti-proliferative agent.

Molecular Modeling Studies of Some Uracil and New Deoxyuridine Derivatives

Molecular modeling results reported in this paper are crucial in highlighting the quantitative relationship between the optimized structure and computed molecular properties related to four newly synthesized uracil derivatives with promising biological potential as anticancer bioactive agents. Moreover, 5-fluorouracil (5-FU) and its tautomers and thiouracils molecular properties are studied and correlated with their biological activities. The great medical importance of these and similar molecular systems requires research on their quantitative structure-activity relationships (QSAR) in order to further improve our knowledge about how receptor binding, selectivity, and pharmacological effects are achieved. Modeling is performed in the ground and the first singlet excited states using density functional theory (DFT) and its time-dependent extension (TD-DFT), respectively.