Design, synthesis of novel chromene-based scaffolds targeting hepatocellular carcinoma: Cell cycle arrest, cytotoxic effect against resistant cancer cells, apoptosis induction, and c-Src inhibition.

New chromene derivatives were synthesized based on 4-(3,4-dimethoxy)-4H-chromene scaffold. All target compounds exhibited cytotoxic activity against HepG2 cells (IC50 = 2.40-141.22 µM). Chromens 5 and 9 showed superior cytotoxicity over staurosporine (IC50 = 18.27 µM) and vinblastine (IC50 = 5.20 µM). c-Src kinase inhibition assay of compounds 5 and 9 displayed the dominant c-Src inhibitory activity of 5 (IC50 = 0.184 µM) over 9 (IC50 = 0.288 µM). The safety of the most potent compound 5 against normal WI-38 cells was confirmed via its IC50 of 115.75 µM comparable with 5-FU (IC50 = 16.28 µM). Moreover, the promising chromene 5 displayed potent cytotoxicity against resistant HepG2 cells with IC50 of 26.03 µM comparable with 5-FU (IC50 = 42.68 µM). The most active chromene 5 arrested the HepG2 cell cycle at the S phase and induced a 29-fold increase in the total number of apoptotic cells indicating pre-G1 apoptosis. The ability of compound 5 to induce apoptosis was supported via elevation of caspase-3, caspase-7, caspase-9 and proapoptotic Bax protein levels in addition to downregulation of the antiapoptotic Bcl2 protein. Molecular docking studies of compound 5 showed good binding interaction pattern inside c-Src kinase enzyme active site.

Methanesulfonamide derivatives as gastric safe anti-inflammatory agents: Design, synthesis, selective COX-2 inhibitory activity, histopathological and histochemical studies.

Novel chalcone 3a-c, pyrazoline 4a-i and pyridine 5a-c, 6a&b derivatives bearing methanesulfonamide moiety were synthesized. Their construction was confirmed using spectral data and elemental analysis. The stereo-chemical configuration for compounds 3a-c was predicted by MM2 property and 1H NMR spectra. All the prepared compounds were screened for their in vitro COX-1/COX-2 inhibitory activities and in vivo anti-inflammatory activity. The most active anti-inflammatory derivatives, 4f-4i, after 3, 5 & 7 h were further subjected to histopathological and histochemical studies showing safe effect on gastric mucosa, especially 4h derivative. To explore the mechanism of action of COX-2 inhibitory compounds 4f and 6b with the highest S.I. values, they were docked inside COX-2 active site. Physicochemical properties for 4f-i and 6b derivatives were predicted and compared to the reference drug celecoxib. They showed good oral bio-availability specially pyrazoline derivative 4f and pyridine containing compound 6b.

Trimethoxyphenyl containing compounds: Synthesis, biological evaluation, nitric oxide release, modeling, histochemical and histopathological studies.

Novel series of trimethoxy phenyl containing chalcone 3, 5, 6, 7, pyrazoline 4a&b, 9a-h and pyrazole 10a&b scaffolds were designed and synthesized. They were characterized by spectral data and elemental analyses. All newly synthesized compounds were screened for their in vitro COX-1/COX-2 inhibitory activities and in vivo anti-inflammatory activity. All the target compounds showed COX-2 inhibitory activity over COX-1. Compound 5c was the most active derivative with higher COX-2 inhibitory activity (IC50 = 0.039 µM) than celecoxib (IC50 = 0.045 µM), and selectivity index value of 321.28 nearly equal to that of celecoxib (S.I. = 326.66). Four additional derivatives 5a, 6, 8b and 9f exhibited excellent COX-2 inhibitory activity (IC50 = 0.041 - 0.049 µM) if compared to the reference drug, celecoxib, with selectivity index values (S.I. = 230.61 - 278.05). Additionally, prolonged in vivo A.I activity was observed in compounds 9e, 9 g, 10a and 10b with % inhibition ranged from 33.21 to 44.52%, after 7 h from carrageenan injection. Compound 9e appeared normal without degeneration similar to celecoxib as resulted from histolopathogical study. Compounds containing NO releasing moieties, 7, 10a and 10b were assesses to overcome the gastrointestinal side effects. Molecular modeling study was operated and achieved a parallel correlation with in vitro COX-2 assay results. Pharmacokinetic study for all the prepared compounds was developed.

Characterization of novel heterocyclic compounds based on 4-aryl-4H-chromene scaffold as anticancer agents: Design, synthesis, antiprofilerative activity against resistant cancer cells, dual ß-tubulin/c-Src inhibition, cell cycle arrest and apoptosis induction.

In this study, three novel sets of 4-aryl-4H-chromene derivatives 4a-c, 6a-d and 7a-c were synthesized and evaluated for anticancer activity. Characterization of new compounds was established on basis of elemental analyses and spectral data. All new compounds were investigated for their antiproliferative activity against HCT-116, HepG-2 and MCF-7 cell lines using vinblastine and staurosporine as positive controls. Compounds 4b, 4c and 6d showed superior cytotoxicity against HCT-116, HepG-2 and MCF-7 cell lines, respectively with IC50 ranged from 3.31 to 4.95 µM. Additionally, compound 4b showed excellent cytotoxic activity (IC50 = 39.83 µM) against resistant HCT-116 better than doxorubicin (IC50 = 164.60 µM), while compounds 4c and 6d exhibited moderate cytotoxic activity against resistant HepG-2 and resistant MCF-7 cell lines. The most potent compounds inhibited both ß-tubulin polymerization (IC50 = 8.78 - 16.47 µM) and c-Src kinase (IC50 = 0.07 - 0.18 µM) enzymes. Compounds 4b, 4c and 6d activated caspase-3, caspase-7, and caspase-9 proteins relative to untreated cells, revealing apoptosis induction. Apoptosis was also confirmed through up-regulation of Bax and down-regulation of Bcl-2 protein expression levels. Cell cycle analysis of compound 6d showed accumulation of cells in pre-G1 phase and cell cycle arrest at S phase in MCF-7 treated cells. As well 6d caused 7- and 63- fold increase in apoptotic cell population at early and late apoptosis stages. Finally, molecular modeling study was performed to predict the binding pattern of the target compounds inside c-Src kinase receptor.

Design, synthesis, and pharmacological evaluation of novel and selective COX-2 inhibitors based on celecoxib scaffold supported with in vivo anti-inflammatory activity, ulcerogenic liability, ADME profiling and docking study.

Four new series of 1,2,4 triazole derivatives 4a,b 5a-d, 6a-f, and 7a,b possessing methylsulphonylphenyl moiety as COX-2 pharmacophore were designed and synthesized. The target compounds were prepared and evaluated in-vitro against COX-1 and COX-2 enzymes. Compounds 4a, 5b, 6a, and 7a showed the highest selectivity towards the COX-2 enzyme (S.I. = 8.64-14.58) in comparison to celecoxib (S.I. = . 6.44). Interestingly, compounds 4a, 6a, and 7a showed good anti-inflammatory activity with edema inhibition (54.17, 53.03, and 50.29 %, in order) relative to the reference drug celecoxib (49.60%) after 3 h. Additionally, these potent derivatives 4a, 5b, 6a and 7a were significantly less ulcerogenic (U.I. = 2.27-2.97) than both reference drugs celecoxib (U.I. = 2.99) and indomethacin (U.I. = 20.25). Besides, a histopathological study of the stomach was also included. Moreover, docking simulation for the most selective compounds 4a, 5b, 6a, and 7a inside COX-2 active site was performed to explain their binding mode. Finally, an ADME study was applied and proved the promising activity of the new compounds as a new oral anti-inflammatory agent. In conclusion, the above findings reveal that newly developed compounds 4a, 6a, and 7a represent a potential selective COX-2 NSAID candidate with minimum gastrointestinal risks.

Optimization of pyrazole-based compounds with 1,2,4-triazole-3-thiol moiety as selective COX-2 inhibitors cardioprotective drug candidates: Design, synthesis, cyclooxygenase inhibition, anti-inflammatory, ulcerogenicity, cardiovascular evaluation, and molecular modeling studies.

The cardiovascular side effects associated with COX-2 selective drugs were the worst for coxibs leading to their withdrawal from the market a few years after their discovery. Therefore, the design of new series of pyrazole (4a,b 5a,b, 7a,b, 9a,b, 10a-h, and 11a-f) substituted with a triazole moiety as selective COX-2 inhibitors with cardioprotective effect was aimed in this paper. The target compounds were prepared and evaluated in-vitro against COX-1 and COX-2 enzymes. Compound 5-(5-Methyl-1-phenyl-1H-pyrazol-4-yl)-4H-1,2,4-triazole-3-thiol (7a) showed the highest selectivity towards COX-2 enzyme (S.I. = 27.56) and was the most active anti-inflammatory agent. Interestingly, its cardiovascular profile showed the cardiac biomarkers (ALP, AST, CK-MB, and LDH), as well as inflammatory cytokines named (TNF-α and IL-6) nearly similar to the control. Besides, a histopathological study of the heart muscle and the stomach was also included. The results confirmed that compound 7a has a more favorable cardio profile than celecoxib. Moreover, docking simulation for the most selective compounds 4b, 7a, 10e, 11c, and 11e inside COX-2 active site was performed to explain their binding mode. Finally, an ADME study was applied and proved the promising activity of the new compounds as a new oral anti-inflammatory agent. In conclusion, the newly developed compound 7a represents a potential selective COX-2 NSAID candidate with minimum cardiovascular risks.

New indomethacin analogs as selective COX-2 inhibitors: Synthesis, COX-1/2 inhibitory activity, anti-inflammatory, ulcerogenicity, histopathological, and docking studies.

New indomethacin analogs 4a-g, 5, 6, 8a, and 8b were synthesized to overcome the nonselectivity and ulcer liability of indomethacin. All newly synthesized compounds were more potent against cyclooxygenase 2 (COX-2; IC50 value range: 0.09-0.4 µÐœ) as compared with celecoxib (IC50 = 0.89 µÐœ). Compounds 4a, 4b, 4d, 5, and 6 showed the highest COX-2 selectivity index (SI range = 4.07-6.33) as compared with indomethacin (SI = 1.14) and celecoxib (SI = 3.52). Additionally, 4a, 4b, 4d, 5, and 7 showed good anti-inflammatory activity with edema inhibition (79.36-88.8%), relative to celecoxib (78.96%) and indomethacin (90.43%), after 5 h. Also, ulcerogenic effects and histopathological examination were assessed for the most potent analogs, 4b, 4d, 5, and 6, to determine their safety. The results can shed light on indomethacin analog 5 as a remarkable anti-inflammatory lead compound with a good safety profile (ulcer index = 10.62) close to the nonulcerogenic drug celecoxib (ulcer index = 10.53) and better than indomethacin (ulcer index = 18.50). Docking studies were performed in the COX-2 active site for the most active compounds, to test their selectivity and to confirm their mechanism of action.

Design, synthesis, biological assessment and in silico ADME prediction of new 2-(4-(methylsulfonyl) phenyl) benzimidazoles as selective cyclooxygenase-2 inhibitors.

A novel series of benzimidazole derivatives wherein 4-(methylsulfonyl) phenyl pharmacophore attached via its C-2 position was designed and synthesized. These compounds were evaluated in vitro as cyclooxygenase-1(COX-1)/cyclooxygenese-2(COX-2) inhibitors. Furthermore, the synthesized compounds were also in vivo evaluated for their anti-inflammatory activity and ulcerogenic liability. Examination of histopathological lesions was also performed to evaluate the cariogenic effect of most active compounds. In silico prediction of physicochemical properties, ADME, and drug-likeness profiles were also studied. Several compounds as 11b, 11k, 12b, and 12d showed selective inhibition to (COX-2) isozyme. Compound 11b showed the most potent (COX-2) inhibitory activity with (IC50 = 0.10 µM) and selectivity index (SI = 134); the tested compounds also have shown good anti-inflammatory activity. Regarding the ulcerogenic liability, compound 11b was also safest one (Ulcer Index) (UI = 0.83). The results of the molecular docking studies is closely related to the results of the in vitro COX-2 inhibitory activities.

Synthesis of novel halogenated triarylpyrazoles as selective COX-2 inhibitors: Anti-inflammatory activity, histopatholgical profile and in-silico studies.

A novel series of halogenated triarylpyrazoles 12a-l was designed and synthesized. All target compounds showed good in vitro COX-2 inhibitory activity (IC50 = 0.043-0.17 µM) over COX-1 (IC50 = 7.8 - 15.4 µM) relative to celecoxib (COX-1/IC50 = 9.87, COX-2/IC50 = 0.055), with acceptable selectivity index values (SI = 50.6-253.1). Also, they displayed moderate to potent in vivo anti-inflammatory activity (% edema inhibition = 16.9-87.9) comparable to celecoxib (% edema inhibition = 46.6-72.1) as standard drug. Three fluorinated pyrazoles 12a, 12g and 12j, exhibited superior anti-inflammatory activity at all time intervals (% edema inhibition = 42.1-87.9) with better gastric profile (UI = 1.25-2.5) than the traditional NSAID; indomethacin (UI = 14) and were close to the selective COX-2 inhibitor; celecoxib (UI = 1.75). In-silico docking and ADME studies of 12a, 12g and 12j supported the obtained biological data and pointed out their potential use for the development of bio-available, safe and potent anti-inflammatory drugs.

Synthesis and biological evaluation of 2-(4-methylsulfonyl phenyl) indole derivatives: multi-target compounds with dual antimicrobial and anti-inflammatory activities.

Three series of 2-(4-methylsulfonylphenyl) indole derivatives have been designed and synthesized. The synthesized compounds were assessed for their antimicrobial, COX inhibitory and anti-inflammatory activities. Compound 7g was identified to be the most potent antibacterial candidate against strains of MRSA, E. coli, K. pneumoniae, P. aeruginosa, and A. baumannii, respectively, with safe therapeutic dose. Compounds 7a-k, 8a-c, and 9a-c showed good anti-inflammatory activity with excessive selectivity towards COX-2 in comparison with reference drugs indomethacin and celecoxib. Compounds 9a-c were found to release moderate amounts of NO to decrease the side effects associated with selective COX-2 inhibitors. A molecular modeling study for compounds 7b, 7h, and 7i into COX-2 active site was correlated with the results of in vitro COX-2 inhibition assays.

New pyrazole derivatives possessing amino/methanesulphonyl pharmacophore with good gastric safety profile: Design, synthesis, cyclooxygenase inhibition, anti-inflammatory activity and histopathological studies.

New series of pyrazole derivatives Va-c, VIa-c, VIIa-f, and VIII possessing amino/methanesulphonyl moiety as COX-2 pharmacophore were designed and synthesized. All compounds were evaluated for both in vitro COX inhibition and in vivo anti-inflammatory activities and all of them were more potent against COX-2 than COX-1 isozyme and showed good in vivo anti-inflammatory activity. Compounds Va, VIa, VIc and VIIa-c showed good COX-2 SI (246.8-353.8) in comparison with the COX-2 selective drug; celecoxib (326.7). Also, they showed good anti-inflammatory activity with edema inhibition (51-86 and 83-96%) relative to celecoxib (60.6 and 82.8%) after 3 and 5 h respectively. Additionally, these potent derivatives Va, VIa, VIc and VIIa-c were significantly less ulcerogenic (ulcer indexes = 0.7-2.0) than indomethacin (ulcer index = 21.3) and were of acceptable ulcerogenicity when compared with the non-ulcerogenic reference drug celecoxib (ulcer index = 1.3). The obtained ulcerogenic liability data revealed the gastric safety of these derivatives which was confirmed by the histopathological studies. Docking study was performed for all synthesized derivatives to explain their interaction with COX-2 receptor active site.

Synthesis and biological evaluations of novel isoxazoles and furoxan derivative as anti-inflammatory agents.

Novel isoxazoles (10, 12a&b, 15a-c) and the furoxan derivative (14) have been prepared as new safe anti-inflammatory agents from the hydroximoyl 9. All compounds were evaluated for COX-1\COX-2 and most of them showed promising selectivity. The furoxan derivative 14 gave 59% inhibitory activity using carrageenan induced paw rat edema model. Ulcer index experiment and histo-pathological study of stomach samples were also included. Also the proposed binding mode of certain newly synthesized compounds with COX-2 isoform was briefly discussed.

Design, synthesis of celecoxib-tolmetin drug hybrids as selective and potent COX-2 inhibitors.

Three novel series of diarylpyrazole 10b-d and triarylpyrazole derivatives 11a-d &12a-d were synthesized through Vilsmier-Haack condition. The structures of prepared compounds were determined through IR, 1H NMR, 13C NMR, Mass spectral and elemental analysis. Docking of the synthesized compounds over COX-2 active site ensure their selectivity. Moreover, the target compounds were evaluated for both in vitro and in vivo inhibitory activity. All compounds were more selective for COX-2 isozyme than COX-1 isozyme and with excellent anti-inflammatory activity. Compounds 11b, 11d and 12b showed the highest anti-inflammatory activity (67.4%, 62.7%, 61.4% respectively), lower ulcerogenic liability (UI = 2.00, 2.75, 3.25 respectively) than indomethacin (UI = 14) and comparable to celecoxib (UI = 1.75) which were confirmed from the histopatholgical study.

COX-1/COX-2 inhibition assays and histopathological study of the new designed anti-inflammatory agent with a pyrazolopyrimidine core.

Four pyrazolopyrimidine series were prepared with a substitution at position- 4 by Schiff base, triazole, oxadiazole and pyrazole moieties (7a-f, 8a,b, 9a-f, 10a,b and 13a,b), respectively. All the synthesized compounds were evaluated in vitro against COX-2 and in vivo against carrageenan-induced rat paw edema as anti-inflammatory agents. Regarding the anti-inflammatory activity (AI) compounds 7c, 7f, 8a, and 9a showed higher activity with respect to celecoxib. Compounds 9a, 7d, and 7f were closely selective to celecoxib. Also, 7c and 7d were safer than indomethacin and similar to celecoxib as resulted from the histopathological study. In addition, the docking study that showed the binding mode of prominent pyrazolopyrimidine compounds inside the COX-2 receptor. Formation of unexpected pyrazole 13a and 13b was briefly discussed using 2D NMR.

Synthesis and biological evaluations of new nitric oxide-anti-inflammatory drug hybrids.

Three novel series of nitroso derivatives (11-15), isoxazolopyrazoles (17a-c) and isoxazolo[3,4-d]pyridazines (18a-c) were prepared from the hydroxyimoyl chloride 10. In vitro COX1⧹2 inhibition activities were evaluated, both of 17b and 18a proved a promising inhibitory activity with IC50=1.12, 0.78µM in sequent. Carrageenan induced Paw edema, ulcer liability, nitric oxide (NO) release and histopathological study were determined. Most of the prepared compounds showed excellent activities. Reactions of 2-aminopyridine and enaminone with hydroxyimoyl chloride 10 were investigated and proved by 2D NMR. Molecular docking for most active compounds was operated giving a hint for compound-receptor interactions.

Synthesis, anti-inflammatory, cyclooxygenases inhibitions assays and histopathological study of poly-substituted 1,3,5-triazines: Confirmation of regiospecific pyrazole cyclization by HMBC.

Three novel triazines series were prepared. These series are pyrazolines (4a and 4b), pyrazoles (6a, 6b and 8a-d) and isoxazoles (7a and 7b). Such series were designed as COX-2 inhibitors. All compounds were characterized by using spectroscopic methods and elemental analysis. Regarding COX-2, compounds 5b, 4a and 3b were the most active with IC50 in the range of 0.55-0.87 µM. Most of synthesized compounds were relatively more potent to celecoxib (0.78 µM), diclofenac (2.94 µM) and indomethacin (7.24 µM). A molecular modeling study was performed for the most active compounds. Histopathological evaluation also was done to estimate the safety of compounds. Finally, structure elucidation of pyrazole 8 was studied by 2D NMR.

Nitric Oxide-NASIDS Donor Prodrugs as Hybrid Safe Anti-inflammatory Agents.

Selective inhibition of cyclooxygenase-2 (COX-2) isozyme afforded a useful drug design concept that resulted in the development of effective anti-inflammatory drugs that are devoid of adverse side effects, in particular gastrointestinal irritation, ulcerogenicity and renal toxicity attributed to inhibition of the cytoprotective cyclooxygenase-1 (COX-1) isozyme. Unfortunately, some selective COX-2 inhibitory drugs such as rofecoxib and valdecoxib are believed to be responsible for cardiovascular complications. Nitric oxide (NO) is an effective vasodilator that also inhibits platelet aggregation. Therefore hybrid NSAIDs containing NO-donor moieties have been developed to obtain effective treatment of inflammation with reduced GI and cardiovascular side effects. Here we review some of the most promising recent advances in NO-NAISDs donor drug development and summarizes medicinal chemistry efforts in search for new NO-NSAIDs prodrugs in an attempt to pave the way for further development in this promising area of research.

Cyclooxygenase-2 and 15-lipoxygenase inhibition, synthesis, anti-inflammatory activity and ulcer liability of new celecoxib analogues: Determination of region-specific pyrazole ring formation by NOESY.

Two new series of 1,5-diaryl pyrazoline (3a-f) and 1,5-diaryl pyrazole (5a and 5b) were designed as both COX-2 and 15-LOX inhibitors. All the prepared compounds were fully characterized by all spectral and element analysis. Their anti-inflammatory activity and ulcer index were included. Pyrazoline 3f is the most effective with IC50=1.14 and 4.7µM against COX-2 and 15-LOX respectively, and more potent than celecoxib and meclofenamate references. In addition 3a, 3b, 5a, and 5b were safer with low ulcer index than celecoxib. Docking study was performed for the most active compounds such as 2b, 3a, and 3f on COX-2 and 15-LOX enzymes.

Synthesis of new thiazolo-celecoxib analogues as dual cyclooxygenase-2/15-lipoxygenase inhibitors: Determination of regio-specific different pyrazole cyclization by 2D NMR.

Two new series of 1,5-diaryl pyrazoles (5a, 5b, 7a, 7b and 10) and 1,5-diaryl pyrazoline (12a and 12b) were prepared as both Cyclooxygenase-2 and 15-lipoxygenase inhibitors. Carrageenan-induced rat paw edema, ulcer index and anti-COX-1/COX-2 and 15-LOX inhibition assays were also included. Cyclization of different pyrazoles was discussed using 2D NMR such as HSQC, HMBC and NOSEY determinations. Compound 5a is more effective with ED50 = 0.98 and 3.98 µM against COX-2 and 15-lipoxygenase respectively, than the references celecoxib (1.54 µM) and meclofenamate sodium (5.64 µM).