29182-93-2Relevant articles and documents
Design, synthesis and antitrypanosomal activity of heteroaryl-based 1,2,4-triazole and 1,3,4-oxadiazole derivatives
Abdel-Aziz, Mohamed,Gouda, Ahmed M.,Marzouk, Adel A.,Radwan, Mohamed M.,Shaykoon, Montaser Sh.,Soltan, Osama M.,Wanas, Amira S.,Youssif, Bahaa G. M.
, (2020)
Two series of novel 1,2,4-triazol-3-yl-thioacetamide 3a-b and 4a-b and 5-pyrazin-2-yl-3H-[1,3,4]oxadiazole-2-thiones 9a-h were designed and synthesized. The compounds prepared have been identified using 1H NMR, 13C NMR and elemental analyses. The synthesized compounds 3a, 3b, 4a, 4b, 9a, 9b, 9d-e and 9f have been evaluated with α-difluoromethylornithine (DFMO) as a control drug for their in vitro antitrypanosomal activity against Trypanosoma brucei. Results showed that 3b was the most active compound in general and also more potent than control DFMO. 3b was 8 folds more potent than the reference with IC50 of 0.79 μM and IC90 of 1.35 μM, respectively compared to DFMO (IC50 = 6.10 μM and IC90 of 8.66 μM). The tested compounds showed moderate cytotoxicity with selectivity indices ranging from 12 (9d) to 102 (3b) against L6 cells. Docking study was performed into ten of T. brucei enzymes which have been identified as potential/valid targets for most of the antitrypanosomal agents. The results of the docking study revealed high binding scores toward many of the selected enzymes. A good correlation was observed only between log (IC50) of antitrypanosomal activity of the new compounds and their calculated Ki values against TryR enzyme (R2 = 0.726). Compound 3b, the most active as antitrypanosomal agents exhibited similar binding orientation and interaction to those of WP6 against TryR enzyme. However, in a next round of work, a complementary studies will be carried out to clarify the mechanism of action of these compounds.
Synthesis and antimicrobial evaluation of new nitric oxide-donating fluoroquinolone/oxime hybrids
Aziz, Hossameldin A.,Moustafa, Gamal A. I.,Abuo-Rahma, Gamal El-Din A.,Rabea, Safwat M.,Hauk, Glenn,Krishna, Vagolu S.,Sriram, Dharmarajan,Berger, James M.,Abbas, Samar H.
, (2020/10/02)
A new series of nitric oxide-donating fluoroquinolone/oximes was prepared in this study. The nitric oxide release from the prepared compounds was measured using a modified Griess colorimetric method. The antitubercular evaluation of the synthesized compounds indicated that ketone derivatives 2b and 2e and oximes 3b and 3d exhibited somewhat higher activity than their respective parent fluoroquinolones. Mycobacterial DNA cleavage studies and molecular modeling of Mycobacterium tuberculosis DNA gyrase were pursued to explain the observed bioactivity. More important, antibacterial evaluation showed that oximes 3c–e are highly potent against Klebsiella pneumoniae, with minimum inhibitory concentration (MIC) values of 0.06, 0.08, and 0.034 μM, respectively, whereas ketone 2c and oxime 4c are more active against Staphylococcus aureus than ciprofloxacin (MIC values: 0.7, 0.38, and 1.6 μM, respectively). Notably, the antipseudomonal activities of compounds 2a and 4c were much higher than those of their respective parent fluoroquinolones.
NO-releasing STAT3 inhibitors suppress BRAF-mutant melanoma growth
Kaoud, Tamer S.,Mohassab, Aliaa M.,Hassan, Heba A.,Yan, Chunli,Van Ravenstein, Sabrina X.,Abdelhamid, Dalia,Dalby, Kevin N.,Abdel-Aziz, Mohamed
, (2019/12/09)
Constitutive activation of STAT3 can play a vital role in the development of melanoma. STAT3-targeted therapeutics are reported to show efficacy in melanomas harboring the BRAFV600E mutant and also in vemurafenib-resistant melanomas. We designed and synthesized a series of substituted nitric oxide (NO)-releasing quinolone-1,2,4-triazole/oxime hybrids, hypothesizing that the introduction of a STAT3 binding scaffold would augment their cytotoxicity. All the hybrids tested showed a comparable level of in vitro NO production. 7b and 7c exhibited direct binding to the STAT3-SH domain with IC50 of ～ 0.5 μM. Also, they abrogated STAT3 tyrosine phosphorylation in several cancer cell lines, including the A375 melanoma cell line that carries the BRAFV600E mutation. At the same time, they did not affect the phosphorylation of upstream kinases or other STAT isoforms. 7c inhibited STAT3 nuclear translocation in mouse embryonic fibroblast while 7b and 7c inhibited STAT3 DNA-binding activity in the A375 cell line. Their anti-proliferating activity is attributed to their ability to trigger the production of reactive oxygen species and induce G1 cell cycle arrest in the A375 cell line. Interestingly, 7b and 7c showed robust cell growth suppression and apoptosis induction in two pairs of BRAF inhibitor-na?ve (-S) and resistant (-R) melanoma cell lines containing a BRAF V600E mutation. Surprisingly, MEL1617-R cells that are known to be more resistance to MEK inhibition by GSK1120212 than MEL1617-S cells exhibit a similar response to 7b and 7c.
