Search

A new series of triazolophthalazine derivatives was designed and synthesized as topoisomerase II (Topo II) inhibitors and DNA intercalators. The synthesized derivatives were evaluated in vitro for their cytotoxic activities against three human cancer cell lines: HepG2, MCF-7, and HCT-116 cells. Compound IX b was the most potent counterpart with IC 50 values of 5.39 ± 0.4, 3.81 ± 0.2, and 4.38 ± 0.3 µM, as it was about 1.47, 1.77, and 1.19 times more active than doxorubicin (IC 50  = 7.94 ± 0.6, 6.75 ± 0.4, and 5.23 ± 0.3 µM) against HepG2, MCF-7, and HCT-116 cells, respectively. Additionally, the binding affinity of the synthesized compounds toward the DNA molecule was assessed using the DNA/methyl green assay. Compound IX b showed an excellent DNA binding affinity with an IC 50 value of 27.16 ± 1.2 µM, which was better than that of the reference drug doxorubicin (IC 50  = 31.02 ± 1.80 µM). Moreover, compound IX b was the most potent member among the tested compounds when investigated for their Topo II inhibitory activity. Furthermore, compound IX b induced apoptosis in HepG2 cells and arrested the cell cycle at the G2/M phase. Additionally, compound IX b showed Topo II poisoning effects at 2.5 μM and Topo II catalytic inhibitory effects at 5 and 10 μM. Finally, molecular docking studies were carried out against the DNA-Topo II complex and DNA, to investigate the binding patterns of the designed compounds., (© 2021 Deutsche Pharmazeutische Gesellschaft.)

Herein we report the design and synthesis of a new series of phthalazine derivatives as Topo II inhibitors and DNA intercalators. The synthesized compounds were in vitro evaluated for their cytotoxic activities against HepG-2, MCF-7 and HCT-116 cell lines. Additionally, Topo II inhibitory activity and DNA intercalating affinity were investigated for the most active compounds as a potential mechanism for the anticancer activity. Compounds 15h, 23c, 32a, 32b, and 33 exhibited the highest activities against Topo II with IC 50 ranging from 5.44 to 8.90 µM, while compounds 27 and 32a were found to be the most potent DNA binders at IC 50 values of 36.02 and 48.30 µM, respectively. Moreover, compound 32a induced apoptosis in HepG-2 cells and arrested the cell cycle at the G2/M phase. Besides, compound 32a showed Topo II poisoning effect at concentrations of 2.5 and 5 μM, and Topo II catalytic inhibitory effect at a concentration of10 μM. In addition, compound 32b showed in vivo a significant tumor growth inhibition effect. Furthermore, molecular docking studies were carried out against DNA-Topo II complex and DNA to investigate the binding patterns of the designed compounds., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A series of anilinophthalazine derivatives 4a-j was initially synthesized and tested for its VEGFR-2 inhibitory activity where it showed promising activity (IC50 = 0.636-5.76 μM). Molecular docking studies guidance was used to improve the binding affinity for series 4a-j towards VEGFR-2 active site. This improvement was achieved by increasing the hydrophobic interaction with the hydrophobic back pocket of the VEGFR-2 active site lined with the hydrophobic side chains of Ile888, Leu889, Ile892, Val898, Val899, Leu1019 and Ile1044. Increasing the hydrophobic interaction was accomplished by extending the anilinophthalazine scaffold with a substituted phenyl moiety through an uriedo linker which should give this extension the flexibility required to accommodate itself deeply into the hydrophobic back pocket. As planned, the designed uriedo-anilinophthalazines 7a-i showed superior binding affinity than their anilinophthalazine parents (IC50 = 0.083-0.473 μM). In particular, compounds 7g-i showed IC50 of 0.086, 0.083 and 0.086 μM, respectively, which are better than that of the reference drug sorafenib (IC50 = 0.09 μM)., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

A series of phthalazinedione bearing substituted oxadiazole moiety derivatives X(1-7) were synthesized in good yield and evaluated for their possible anticonvulsant activity. The structures of the synthesized compounds were confirmed on the basis of their spectral data and elemental analysis. Their anticonvulsant activities were evaluated by the maximal electroshock induced seizure (MES) and subcutaneous pentylenetetrazole (PTZ) tests. All the tested compounds showed considerable anticonvulsant activities in at least one of the anticonvulsant tests. Moreover, some of the tested compounds exhibited moderate anticonvulsant activities in both MES and PTZ tests. From these results,[3-)2-Alkoxycarbonylmethylthioxadiozol-5-yl)methyl -6-Iodophthalazine - 1,4- (2H,3H)-1,4-dion] (X1-7) derivatives could be recommended as novel structures of broad spectrum anticonvulsants., (© Georg Thieme Verlag KG Stuttgart · New York.)