Synthesis and characterization of new phthalhydrazothiazole derivatives: A preliminary investigation on their activity against hepatocellular carcinoma

Synthesis of new oxadiazol-phthalazinone derivatives with anti-proliferative activity; molecular docking, pro-apoptotic, and enzyme inhibition profile

Background and aim: The current study reports the synthesis and biological evaluation of two novel series of 4-(5-mercapto-1,3,4-oxadiazol-2-yl)phthalazin-1(2H)-one derivatives. Methods: The synthetic reactions were carried out under both conventional and ultrasonic irradiation conditions. The anti-proliferative activity of the newly synthesized compounds against two human epithelial cell lines; liver (HepG2) and breast (MCF-7) in addition to normal fibroblasts (WI-38) was investigated. In addition to molecular docking studies, the possible mechanism(s) of action were also explored. Results: In general, an improvement in synthetic rates and yields was observed when reactions were carried out under sonication compared with classical conditions. The structures of the products were established based on analytical and spectral data. Derivatives 2e and 7d, in addition to compound 1, had significant and selective anti-proliferative activity against liver and breast cancer cell lines without harming normal fibroblasts. These derivatives arrested the cell cycle progression and/or induced apoptosis. This has been manifested by the elevation in the expression of p53 and caspase 3, down-regulation of cdk1, and a reduction in the concentrations of MAPK and Topo II at submicromolar concentrations. The latter results confirmed the molecular docking study. Conclusions: Compound 1 had the best profile on the gene and protein levels (arresting cell cycle and inducing apoptosis). The ability of compounds 1 and 2e to inhibit both MAPK and Topo II nominates these derivatives as potential candidates for further anticancer and antitumor studies.

An Efficient Synthesis of Novel Bioactive Thiazolyl-Phthalazinediones under Ultrasound Irradiation

Novel 2-thiazolylphthalazine derivatives were efficiently synthesized under ultrasound irradiation, resulting in high yields and short reaction times after optimization of the reaction conditions. All prepared compounds were fully characterized using spectroscopic methods. They were screened for their antimicrobial activity against Gram-positive and Gram-negative bacteria as well as for antifungal activity. The antimicrobial activity profile of the tested compounds showed some promising results. The potent activity of compounds 4d, 7b (117% zone inhibition) and 7c (105% zone inhibition) against Salmonella sp., exceeding that of the reference drug Gentamycin is particularly noteworthy. In general, the newly synthesized thiazolylphthalazine derivatives showed higher antimicrobial activity against the tested Gram-negative bacteria than against Gram-positive bacteria and fungi.