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A series of 3-acetyl-2-aryl-5-methylthio-2,3-dihydro-1,3,4-thiadiazoles 3a–g,N- (4-acetyl-5-aryl-4,5-dihydro-1,3,4-thiadiazol-2-yl) acetamide derivatives 5a–e and spiro-compound 7 was prepared from starting material dithiocarbazates using N-methylpyrrolidone (NMP) /acetic anhydride mixture. Furthermore, a new series of 5-amino-3- (methylthio) -1-substituted-1H-pyrazole-4-carbonitrile derivatives 12a–d was prepared using two synthetic routes: (i) via reaction of bis (methylthio) methylene malononitrile 8 with carbothiohydrazides 11a–d, or (ii) via reaction of methyl 5-amino-4-cyano-3- (methylthio) -1H-pyrazole-1-carbodithioate 9a with primary/secondary amines. The antimicrobial screening of newly synthesized compounds revealed that compounds 3b, 7, and 12d are the most potent against the Gram-positive (S. aureus) and the Gram-negative (E. coli) bacteria compared to ciprofloxacin as reference drug. Mechanistically, the theoretical docking results of 3b, 7 and 12d suggested that they may act as potent inhibitors of theDNA gyrase. [ABSTRACT FROM AUTHOR]

Since the synthesis of prontosil the first prodrug shares their chemical moiety, sulfonamides exhibit diverse modes of actions to serve as antimicrobials, diuretics, antidiabetics, and other clinical applications. This inspiring chemical nucleus has promoted several research groups to investigate the synthesis of new members exploring new clinical applications. In this study, a novel series of 5(4H)-oxazolone-based-sulfonamides (OBS) 9a–k were synthesized, and their antibacterial and antifungal activities were evaluated against a wide range of Gram-positive and -negative bacteria and fungi. Most of the tested compounds exhibited promising antibacterial activity against both Gram-positive and -negative bacteria particularly OBS 9b and 9f. Meanwhile, compound 9h showed the most potent antifungal activity. Moreover, the OBS 9a, 9b, and 9f that inhibited the bacterial growth at the lowest concentrations were subjected to further evaluation for their anti-virulence activities against Pseudomonas aeruginosa and Staphylococcus aureus. Interestingly, the three tested compounds reduced the biofilm formation and diminished the production of virulence factors in both P. aeruginosa and S. aureus. Bacteria use a signaling system, quorum sensing (QS), to regulate their virulence. In this context, in silico study has been conducted to assess the ability of OBS to compete with the QS receptors. The tested OBS showed marked ability to bind and hinder QS receptors, indicating that anti-virulence activities of OBS could be due to blocking QS, the system that controls the bacterial virulence. Furthermore, anticancer activity has been further performed for such derivatives. The OBS compounds showed variable anti-tumor activities, specifically 9a, 9b, 9f and 9k, against different cancer lines. Conclusively, the OBS compounds can serve as antimicrobials, anti-virulence and anti-tumor agents. [ABSTRACT FROM AUTHOR]

New pyrazolo[3,4-d]pyrimidine derivatives 7a-h and 8a-h were synthesized and evaluated for their in vitro inhibitory potential against COX-1, COX-2, 5-LOX along with the NO release inhibitory activity to assess their anti-inflammatory potential. Most compounds confered inhibitory activity at a micromolar level and exhibited prominent selectivity towards COX-2 especially in the 8a-h series. The most useful compound 8e as a COX-2/5-LOX dual inhibitor, exhibited IC 50 results of; 1.837 µM for COX-2, 2.662 µM for 5-LOX with an acceptable NO release inhibition rate of 66.02 %. Compounds 7e, 7f, 8e and 8f proved their efficiency as 5-LOX/NO release dual inhibitors; with IC 50 values of 2.833, 1.952, 2.662 and 1.573 µM, respectively for 5-LOX biotarget, and with superior NO inhibitory ratio of 73.85, 65.57, 66.02 and 72.28 %, respectively. The in vivo anti-inflammatory assay explored that 7e is the most effective with minimal gastric ulceration prevalence. Molecular docking in the active site of both COX-2 and 5-LOX showed that, the most active 8e and 7e are correctly oriented inside the COX-2 binding pocket with unique binding mode independently on the reference celecoxib. Also, they demonstrated superior binding affinities to the 5-LOX enzyme over both the Zileuton as a reference drug and the normal ligand 30Z. The stability of the complex formed between the most promising candidates 7e or 8e with the COX-2 and 5-LOX active sites, was considered using a typical atomistic 100 ns dynamic simulation study. Investigation of the SAR revealed the importance of both the sulfonamide group in the 8a-h series and the substituents of the 3-phenyl ring tethered on the 1,2,4-oxadiazole core., 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 © 2025 Elsevier Inc. All rights reserved.)

Aims: Ulcerative colitis (UC) is characterized by the up-regulation of pro-inflammatory mediators, apoptotic signals, and oxidative stress that can lead to an increased risk of colorectal cancer. The present study aims to investigate the possible role of myristicin in modulating endoplasmic reticulum stress (ERS) and risk-associated conditions in acetic acid (AA)-induced UC., Materials and Methods: Adult male rats were treated with 150 mg/kg body weight of myristicin or mesalazine orally either as pre/post treatment or post-treatment only. The gene expression of glucose-related protein 78 (GRP78), CCAAT/enhancer-binding protein homologous protein (CHOP), and nuclear factor kappa B (NF-κB), percentage of DNA fragmentation, and serum levels of some oxidative and inflammatory markers were measured., Key Findings: The results indicated the potential upregulation of ERS, pro-apoptotic, lipid peroxidation, and pro-inflammatory cascades by induction of UC in rats. However, myristicin could effectively reverse the deteriorated effects of ulceration in colonic mucosa. It was mediated through downregulation of the ERS markers GRP78 and CHOP genes expression, reduction of NF-κB mRNA expression, DNA fragmentation, reduced lipid peroxidation, myeloperoxidase (MPO) activity and pro-inflammatory markers (Tumor necrosis factor-α (TNF-α), Interleukin-1β (IL-1β) and cyclo‑oxygenase (COX-2) activity). Accompanied by elevated levels of IL-10, colonic Nuclear erythroid factor (Nrf-2) and Heme oxygenase (HO-1) activity as well as blood antioxidant enzymes activity. Results of docking might confirm the biological results of our study., Significance: Myristicin could effectively modulate important stress, and inflammatory effectors and protect mucosal DNA from oxidative damage which can serve as a promising candidate for the treatment of ulcerative colitis., Competing Interests: Declaration of competing interest No potential conflict of interest was reported by the author., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Uncontrolled inflammation predisposes to pleiotropic effects leading to cancer development thanks to promoting all stages of tumorigenesis. Therefore, cancer-associated inflammation has been delegated as the seventh hallmark of cancer. Thus, raging the war against both inflammation and cancer via the innovation of bioactive agents with dual anti-inflammatory and anticancer activities is a necessity. Herein, a novel series of pyrazole-chalcone analogs of Lonazolac (7a-g and 8a-g) have been synthesized and investigated for their in vitro anticancer activity against four cancer cell lines using the MTT assay method. Among all, hybrid 8g was the most potent against three cancer cell lines, HeLa, HCT-116, and RPMI-822 with IC 50 values of 2.41, 2.41, and 3.34 µM, respectively. In contrast, hybrid 8g showed moderate inhibitory activity against MCF-7 with IC 50 28.93 μM and with a selectivity profile against MCF-10A (non-cancer cells). Mechanistically, hybrid 8g was the most potent inhibitor against tubulin polymerization (IC 50  = 4.77 µM), suggesting tubulin as a molecular target and explaining the observed cytotoxicity of hybrid 8g. This was mirrored by the detected potent pre-G1 apoptosis induction and G2/M cell cycle arrest. Moreover, hybrid8gexhibited selectivity against COX-2 (IC 50  = 5.13 µM) more than COX-1 (IC 50  = 33.46 µM), indicating that 8g may have lower cardiovascular side effects, but is still not potent as celecoxib (COX-2 IC 50  = 0.204 µM, COX-1 = 35.8 µM). Notably, hybrid 8g showed promising inhibitory activity towards 5-LOX (IC 50  = 5.88 µM). Finally, the anti-inflammatory activity of hybrid8 g was confirmed by high iNOS and PGE2 inhibitory activities in LPS-stimulated RAW cells with IC 50 values of4.93 µM and 10.98 µM, respectively, that accompanied by showingthe most potent inhibition of NO release (70.61 % inhibition rate). Molecular docking studies of hybrid 8g confirmed good correlations with the executed biological results. Furthermore, hybrid 8g had good drug-likeness and suitable physicochemical properties. Taken together, the combined results suggested hybrid8gas a promising orally administered candidate in the journey of repurposing NSAIDs for cancer chemopreventionand treatment., 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 © 2022 Elsevier Inc. All rights reserved.)

Herein, we report design and synthesis of twenty-one dual PIM-1/HDAC inhibitors utilizing 3-cyanopyridines as a novel cap moiety linked with aliphatic /aromatic linker bearing carboxylic acid 3a-g, hydroxamic acid 4a-g or 2-aminoanilide moieties 5a-g as zinc-binding group. Most of the target hybrids revealed promising growth inhibition according to one dose NCI protocol against 60 cancer cell lines. Meanwhile, hydroxamic acids 4b, 4d and 4e displayed strong and broad-spectrum activity against nine tumor subpanels tested (GI 50 0.176-8.87 μM); 4d displayed strong antiproliferative activity with GI 50  ≤ 3 μM against different cancer cell lines (GI 50 range from 0.325 to 2.9 μM). Furthermore, 4a, 4d-4g and 5f manifested a high inhibitory activity against HDACs 1 and 6 isozymes; 4g, displayed potent HDAC 1 and 6 inhibitory activity (45.01 ± 2.1 and 19.78 ± 1.1 nM) more than the reference SAHA (51.54 ± 2.4 and 21.38 ± 1.2 nM, respectively), while 4f was more potent (30.09 ± 1.4 nM) than SAHA against HDAC 1 and less potent (30.29 ± 1.7 nM) than SAHA against HDAC 6. Hybrids 4b, 4d, 4e and 4f exhibited potent PIM-1 inhibitory activity; 4d showed comparable activity to quercetin (IC 50 of 343.87 ± 16.6 and 353.76 ± 17.1 nM, respectively); it exhibited pre G1 apoptosis and arrest cell cycle at G2/M phase. Moreover, it revealed good binding into pocket of HDACs 1,6 and PIM-1 kinase enzymes with good correlation with biological results. Moreover, 4b, 4d and 4e had reasonable drug-likeness properties according to Lipinski's rule. However, multitarget inhibitor of PIM-1/HDAC is a promising strategy in anticancer drug discovery; the most potent hybrids require further in vivo and clinical investigations., (Copyright © 2021 Elsevier Inc. All rights reserved.)

DNA gyrase and topoisomerase IV (topo IV) inhibitors are among the most interesting antibacterial drug classes without antibacterial pipeline representative. Twenty-four new quinoline-1,3,4-oxadiazole and quinoline-1,2,4-triazole hybrids were developed and tested against DNA gyrase and topoisomerase IV from Escherichia coli and Staphylococcus aureus. The most potent compounds 4c, 4e, 4f, and 5e displayed an IC 50 of 34, 26, 32, and 90 nM against E. coli DNA gyrase, respectively (novobiocin, IC 50  = 170 nM). The activities of 4c, 4e, 4f, and 5e on DNA gyrase from S. aureus were weaker than those on E. coli gyrase. Compound 4e showed IC 50 values (0.47 µM and 0.92 µM) against E. coli topo IV and S. aureus topo IV, respectively in comparison to novobiocin (IC 50  = 11, 27 µM, respectively). Antibacterial activity against Gram-positive and Gram-negative bacterial strains has been studied. Some compounds have demonstrated superior antibacterial activity to ciprofloxacin against some of the bacterial strain studied. The most active compounds in this study showed no cytotoxic effect with cell viability>86%. Finally, a molecular docking analysis was performed to investigate the binding mode and interactions of the most active compounds to the active site of DNA gyrase and topoisomerase IV (topo IV) enzymes., (Copyright © 2021 Elsevier Inc. All rights reserved.)

New antibacterial drugs are urgently needed to tackle the rapid rise in multi-drug resistant bacteria. DNA gyrase is a validated target for the development of new antibacterial drugs. Thus, in the present investigation, a novel series of 1,2,4-oxadiazole-chalcone/oxime (6a-f) and (7a-f) were synthesized and characterized by IR, NMR ( 1 H and 13 C) and elemental analyses. The title compounds were evaluated for their in-vitro antimicrobial activity by the modified agar diffusion method as well as their E. coli DNA gyrase inhibitory activity. The minimum inhibitory concentration (MIC) and the structure activity relationships (SARs) were evaluated. Among all, compounds 6a, 6c-e, 7b and 7e were the most potent and proved to possess broad spectrum activity against the tested Gram-positive and Gram-negative organisms. Additionally, compounds 6a (against S. aureus), 6c (against B. subtilis and E. hirae), 6e (against E. hirae), 6f, 7a and 7c (against E. coli) and 7d (against B. subtilis), with MIC value of 3.12 μM were two-fold more potent than the standard ciprofloxacin (MIC = 6.25 μM). Mechanistically, compounds 6c, 7c, 7e and 7b had good inhibitory activity against E. coli gyrase with IC 50 values of 17.05, 13.4, 16.9, and 19.6 µM, respectively, in comparison with novobiocin (IC 50  = 12.3 µM) and ciprofloxacin (IC 50  = 10.5 µM). The molecular docking results at DNA gyrase active site revealed that the most potent compounds 6c and 7c have binding mode and docking scores comparable to that of ciprofloxacin and novobiocin suggesting their antibacterial activity via inhibition of DNA gyrase. Finally, the predicted parameters of Lipinski's rule of five and ADMET analysis showed that 6c and 7c had good drug-likeness and acceptable physicochemical properties. Therefore, the hybridization of the chalcone and oxadiazole moieties could be promising lead as antibacterial candidate which merit further future structural optimizations., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Despite the encouraging clinical progress of chemotherapeutic agents in cancer treatment, innovation and development of new effective anticancer candidates still represents a challenging endeavor. With 15 million death every year in 2030 according to the estimates, cancer has increased rising of an alarm as a real crisis for public health and health systems worldwide. Therefore, scientist began to introduce innovative solutions to control the cancer global health problem. One of the promising strategies in this issue is the multitarget or smart hybrids having two or more pharmacophores targeting cancer. These rationalized hybrid molecules have gained great interests in cancer treatment as they are capable to simultaneously inhibit more than cancer pathway or target without drug-drug interactions and with less side effects. A prime important example of these hybrids, the HDAC hybrid inhibitors or referred as multitargeting HDAC inhibitors. The ability of HDAC inhibitors to synergistically improve the efficacy of other anti-cancer drugs and moreover, the ease of HDAC inhibitors cap group modification prompt many medicinal chemists to innovate and develop new generation of HDAC hybrid inhibitors. Notably, and during this short period, there are four HDAC inhibitor hybrids have entered different phases of clinical trials for treatment of different types of blood and solid tumors, namely; CUDC-101, CUDC-907, Tinostamustine, and Domatinostat. This review shed light on the most recent hybrids of HDACIs with one or more other cancer target pharmacophore. The designed multitarget hybrids include topoisomerase inhibitors, kinase inhibitors, nitric oxide releasers, antiandrogens, FLT3 and JAC-2 inhibitors, PDE5-inhibitors, NAMPT-inhibitors, Protease inhibitors, BRD4-inhibitors and other targets. This review may help researchers in development and discovery of new horizons in cancer treatment., 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 Masson SAS. All rights reserved.)

PDE5 targeting represents a new and promising strategy for apoptosis induction and inhibition of tumor cell growth due to its over-expression in diverse types of human carcinomas. Accordingly, we report the synthesis of series of pyrazolo[3,4-d]pyrimidin-4-one carrying quinoline moiety (11a-r) with potential dual PDE5 inhibition and apoptotic induction for cancer treatment. These hybrids were structurally elucidated and characterized with variant spectroscopic techniques as 1 H NMR, 13 C NMR and elemental analysis. The assessment of their anticancer activities has been declared. All the rationalized compounds 11a-r have been selected for their cytotoxic activity screening by NCI against 60 cell lines. Compounds 11a, 11b, 11j and 11k were the most active hybrids. Among all, compound 11j was further selected for five dose tesing and it displayed outstanding activity with strong antitumor activity against the nine tumor subpanels tested with selectivity ratios ranging from 0.019 to 8.3 at the GI 50 level. Further, the most active targets 11a, b, j and k were screened for their PDE5 inhibitory activity, compound 11j (with IC 50 1.57 nM) exhibited the most potent PDE5 inhibitory activity. Moreover, compound 11j is also showed moderate EGFR inhibition with IC 50 of 5.827 ± 0.46 µM, but significantly inhibited the Wnt/β-catenin pathway with IC 50 1286.96 ± 12.37 ng/mL. In addition, compound 11j induced the intrinsic apoptotic mitochondrial pathway in HepG2 cells as evidenced by the lower expression levels of the anti-apoptotic Bcl-2 protein, and the higher expression of the pro-apoptotic protein Bax, p53, cytochrome c and the up-regulated active caspase-9 and caspase-3 levels. All results confirmed by western blotting assay. Compound 11j exhibit pre G1 apoptosis and cell cycle arrest at G2/M phase. In conclusion, hybridization of quinoline moiety with the privileged pyrazolo[3,4-d]pyrimidinon-4-one structure resulted in highly potent anticancer agent, 11j, which deserves more study, in particular, in vivo and clinical investiagtions, and it is expected that these results would be applied for more drug discovery process., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The development of NSAIDs/iNOS inhibitor hybrids is a new strategy for the treatment of inflammatory diseases by suppression of the overproduction of PGE 2 and NO. A novel series of aryl carboximidamides 4a-g and their cyclized 3-aryl-1,2,4-oxadiazoles 5a-g counterparts derived from indomethacin 1 were synthesized. Most of the target compounds displayed lower LPS-induced NO production IC 50 in RAW 264.7 cells and potent in vitro iNOS and PGE2 inhibitory activity than indomethacin. Moreover, in carrageenan-induced rat paw oedema method, most of them exhibited higher in vivo anti-inflammatory activity than the reference drug indomethacin. Notably, 4 hrs after carrageenan injection, compound 4a proved to be the most potent anti-inflammatory agent in this study, with almost two- and eight-fold more active than the reference drugs indomethacin (1) and celecoxib, respectively. Compound 4a proved to be inhibitor to LPS-induced NO production, iNOS activity and PGE2 with IC 50 of 10.70 μM, 2.31 μM, and 29 nM; respectively. Compounds 4a and 5b possessed the lowest ulcerogenic liabilities (35% and 38%, respectively) compared to 1. Histopathological analysis revealed that compounds 4a and 5b demonstrated reduced degeneration and healing of ulcers. Molecular docking studies into the catalytic binding pocket of the iNOS protein receptor (PDB ID: 1r35) showed good correlation with the obtained biological results. Parameters of Lipinski's rule of five and ADMET analysis were calculated where compound 4a had reasonable drug-likeness with acceptable physicochemical properties so it could be used as promising orally absorbed anti-inflammatory therapy and entitled to be used as future template for further investigations., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Twenty-five valproic acid conjugates have been designed and synthesized. All target compounds were explored for their in vitro anti-proliferative activities using the MTT-based assay against four human cancer cell lines includingliver (HePG2), colon (HCT116), breast (MCF7) and cervical (HeLa) carcinoma cell lines. Out of six valproic acid-amino acid conjugates 2a-f. Only cysteine containing conjugate 2f showed the significant activity (IC 50 9.10 µM against HePG2 and 6.81 µM against HCT116). However conjugate 2j showed broad-spectrum antitumor activity against all cell lines tested. In addition, conjugates 4j and 4k which contains phenyl hydrazide and hydroxamic acid group, respectively, also showed broad spectrum activity. Furthermore, six compounds were screened for HDAC 1-9 isozymes inhibitory activities. Compounds 2j, 4j and 4k manifested a higher inhibitory activity more than valproic acid but less than SAHA. In addition, the in vivo antitumor screening of 2j, 4j and 4k was done and the results have shown that 2j, 4j and 4k, particularly 4j, showed a significant decrease in tumor size and presented a considerable decrease in viable EAC count. Docking study of selectedcompound 4j revealed that it can bind nicely to the binding pocket of HDAC 1, 2, 3, 4 and HDAC 8. The results suggest that compounds 2j, 4j and 4k, particularly 4j, may be promising lead candidates for the development of novel targeted anti-tumor drug potentially via inhibiting HDACs., (Copyright © 2020 Elsevier Inc. All rights reserved.)

A series of novel 5,6,7,8-Tetrahydro[1]benzothieno[2,3-d]pyrimidin-4(3H)-one derivatives bearing a hydroxamic acid, 2-aminoanilide and hydrazide moieties as zinc-binding group (ZBG) were designed, synthesized and evaluated for the HDAC inhibition activity and antiproliferative activity. Most of the tested compounds displayed strong to moderate HDAC inhibitory activity. Some of these compounds showed potent anti-proliferative activity against human HepG2, MCF-7 and HCT-116 cell lines. In particular, compounds IVa, IVb, IXa and IXb exhibited significant anti-proliferative activity against the three cell lines tested compared to SAHA as a reference. Compound IVb is equipotent inhibitor for HDAC1 and HDAC2 as SAHA. It is evident that the presence of free hydroxamic acid group is essential for Zn binding affinity with maximal activity with a linker of aliphatic 6 carbons. Docking study results revealed that compound IVb could occupy the HDAC2 binding site and had the potential to exhibit antitumor activity through HDAC inhibition, which merits further investigation., (Copyright © 2019 Elsevier Inc. All rights reserved.)

One of the helpful ways to improve the effectiveness of anticancer agents and weaken drug resistance is to use hybrid molecules. therefore, the current study intended to introduce 20 novel xanthine/chalcone hybrids 9-28 of promising anticancer activity. Compounds 10, 11, 13, 14, 16, 20 and 23 exhibited potent inhibition of cancer cells growth with IC 50 ranging from 1.0 ± 0.1 to 3.5 ± 0.4 μM compared to doxorubicin with IC 50 ranging from 0.90 ± 0.62 to 1.41 ± 0.58 μM and that compounds 11 and 16 were the best. To verify the mechanism of their anticancer activity, compounds 10, 11, 13, 14, 16, 20 and 23 were evaluated for their EGFR inhibitory effect. The study results revealed that compound 11 showed IC 50  = 0.3 µM on the target enzyme which is more potent than staurosporine reference drug (IC 50  = 0.4 µM). Accordingly, the apoptotic effect of the most potent compounds 11 was extensively investigated and showed a marked increase in Bax level up to 29 folds, and down-regulation in Bcl2 to 0.28 fold, in comparison to the control. Furthermore, the effect of compound 11 on Caspases 3 and 8 was evaluated and was found to increase their levels by 8 and 14 folds, respectively. Also, the effect of compound 11 on the cell cycle and its cytotoxic effect were examined. Moreover, a molecular docking study was adopted to confirm mechanism of action., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A series of novel naproxen analogues containing 3-aryl-1,2,4-oxadiazoles moiety (4b-g) and their reaction intermediates aryl carboximidamides moiety (3b-g) was synthesized and evaluated in vitro as dual COXs/15-LOX inhibitors. Compounds 3b-g exhibited superior inhibitory activity than celecoxib as COX-2 inhibitors. Compounds 3b-d and 3g were the most potent COX-2 inhibitors with IC 50 range of 6.4 - 8.13 nM and higher selectivity indexes (3b, SI = 26.19; 3c, SI = 13.73; 3d, SI = 29.27; 3g, SI = 18.00) comparing to celecoxib (IC 50  = 42.60 nM, SI = 8.05). Regarding 15-LOX inhibitory activity, compounds belonging to aryl carboximidamide backbone 3b-e and 3g were the most potent with IC 50 range of 1.77-4.91 nM comparing to meclofenamate sodium (IC 50  = 5.64 µM). Data revealed that The levels of NO released by aryl carboximidamides 3b-g were more higher than 3-aryl-1,2,4-oxadiazole derivatives 4b-g, which correlated well with their COX-2 inhibitory activities., (Copyright © 2019 Elsevier Inc. All rights reserved.)

A novel quinolinyl pyrrolone and quinolinyl pyridazinone derivatives has been synthesized and characterized using different spectroscopic and elemental analysis techniques. Most of the target compounds displayed promising antiproliferative activity; In general, the pyrrolone derivatives 4a-f exhibited higher antiproliferative activity than their corresponding pyridazinone. The pyrrolone 4f showed outstanding antiproliferative activity with moderate selectivity against CNS and renal cancer with selectivity ratio of 3.49 and 3.56, respectively. Compound 4e and 5d experienced tubulin polymerization inhibitory activity comparable to that of vincristine while 4c, 4e and 4d showed good BRAF kinase inhibition compared to Erlotinib. Docking of compound 4e into colchicine binding site and biological assay results revealed that these compounds act mainly through tubulin polymerization inhibitory mechanism and can exhibit pre G1 apoptosis and cell cycle arrest at G2/M phase., (Copyright © 2018 Elsevier Inc. All rights reserved.)

A series of novel compounds carrying pyrazino[1,2-a]indol-1(2H)-one scaffold (5a-g) and their reaction intermediates, indole-2-carboxamides, (3a-g) were synthesized and evaluated for their ability to inhibit reactive oxygen species (ROS) generation, antioxidant activity and anticancer activity against a panel of cancer cell lines using MTT assay. The results showed that these compounds can inhibit ROS generation during the metabolic phase of phagocytosis in a dose-dependent manner where compounds 5d and 5e were the most potent samples with higher inhibitory activities (IC 50 values 3.3 and 1.4 μM, respectively) than that of the reference acetylsalicylic acid (IC 50  = 9.7 μM). Results for the determination of potential antioxidant properties of the synthesized compounds showed that compounds 5d and 5e containing pyrazino[1,2-a]indol-1-one backbone were the most acive and even comparable to Trolox. Compounds 3d-f and 5d-f with the least IC 50 values in MTT assay were tested against three known anticancer targets EGFR, BRAF and Tubulin. Histopathological and immunohistochemical study were performed to determine the consequence of exposure to chronic low dose of chlorpyrifos on the testis of male mice and results revealed that these effects can be ameliorated by co-treatment with the most active antioxidant compounds 5d and 5e. Finally, molecular docking studies were performed to explore the binding mode of the most active compounds against EGFR and BRAF kinases., (Copyright © 2018 Elsevier Masson SAS. All rights reserved.)

A group of novel chalcone derivatives comprising hydroxamic acid or 2-aminobenzamide group as zinc binding groups (ZBG) were synthesized. The structure of the prepared compounds was fully characterized by IR, NMR and elemental microanalyses. Most of the tested compounds displayed strong to moderate HDAC inhibitory activity. Some of these compounds showed potent anti-proliferative activity against human HepG2, MCF-7 and HCT-116 cell lines. In particular, compounds 4a and 4b exhibited significant anti-proliferative activity against the three cell lines compared to SAHA as reference drug and displayed promising profile as anti-tumor candidates. The results indicated that these chalcone derivatives could serve as a promising lead compounds for further optimization as antitumor agents., (Copyright © 2017 Elsevier Inc. All rights reserved.)