Design, synthesis and anti-inflammatory assessment of certain substituted 1,2,4-triazoles bearing tetrahydroisoquinoline scaffold as COX 1/2-inhibitors.

Aiming to discover effective and safe non-steroidal anti-inflammatory agents, a new set of 1,2,4-triazole tetrahydroisoquinoline hybrids 9a-g, 11a-g and 12a-g was synthesized and evaluated as inhibitors of COX-1 and COX-2. In order to overcome the adverse effects of highly selective COX-2 and non-selective COX-2 inhibitors, the compounds of this study were designed with the goal of obtaining moderately selective COX-2 inhibitors. In this study compounds 9e, 9g and 11f are the most effective derivatives against COX-2 with IC50 values 0.87, 1.27 and 0.58 µM, respectively which are better than or comparable to the standard drug celecoxib (IC50 = 0.82 µM) but with lower selectivity indices as required by our goal design. The results of the in vivo anti-inflammatory inhibition test revealed that compounds 9e, 9g and 11f displayed a higher significant anti-inflammatory activity than celecoxib at all-time intervals. In addition, these compounds significantly decreased the production of inflammatory mediators PGE-2, TNF-ɑ and IL-6. Compounds 9e, 9g and 11f had a safe gastric profile compared to indomethacin, also compound 11f (ulcerogenic index = 1.33) was less ulcerous than the safe celecoxib (ulcerogenic index = 3). Moreover, histopathological investigations revealed a normal architecture of both paw skin and gastric mucosa after oral treatment of rats with compound 11f. Furthermore, molecular docking studies were performed on COX-1 and COX-2 to study the binding pattern of compounds 9e, 9g and 11f on both isoenzymes.

Discovery of novel thiazolyl-pyrazolines as dual EGFR and VEGFR-2 inhibitors endowed with in vitro antitumor activity towards non-small lung cancer.

New series of thiazolyl-pyrazoline derivatives (7a-7d, 10a-10d and 13a-13f) have been synthesised and assessed for their potential EGFR and VEGFR-2 inhibitory activities. Compounds 10b and 10d exerted potent and selective inhibitory activity towards the two receptor tyrosine kinases; EGFR (IC50 = 40.7 ± 1.0 and 32.5 ± 2.2 nM, respectively) and VEGFR-2 (IC50 = 78.4 ± 1.5 and 43.0 ± 2.4 nM, respectively). The best anti-proliferative activity for the examined thiazolyl-pyrazolines was observed against the non-small lung cancer cells (NSCLC). Compounds 10b and 10d displayed pronounced efficacy against A549 (IC50 = 4.2 and 2.9 µM, respectively) and H441 cell lines (IC50 = 4.8 and 3.8 µM, respectively). Moreover, our results indicated that 10b and 10d were much more effective towards EGFR-mutated NSCLC cell lines (NCI-H1650 and NCI-H1975 cells) than gefitinib. Finally, compounds 10b and 10d induce G2/M cell cycle arrest and apoptosis and inhibit migration in A549 cancerous cells.

Design and synthesis of novel coumarin derivatives as potential acetylcholinesterase inhibitors for Alzheimer's disease.

Twenty novel 7-benzyloxycoumarin based compounds were synthesized with a variety of bioactive chemical fragments. The synthesized compounds showed remarkable acetylcholinesterase (AChE) inhibitory activity. In vitro assay revealed that compounds 7-benzyloxy-4-{[(4-phenylthiazol-2(3H)-ylidene)hydrazono]methyl}-2H-chromen-2-one (5b, IC50= 0.451µM), 7-benzyloxy-4-({[4-(4-methoxyphenyl)thiazol-2(3H)-ylidene]hydrazono}methyl)-2H-chromen-2-one (5d, IC50= 0.625µM), 5-amino-1-[2-(7-benzyloxy-2-oxo-2H-chromen-4-yl)acetyl]-1H-pyrazole-4-carbonitrile (13c, IC50= 0.466µM), 2-(7-benzyloxy-2-oxo-2H-chromen-4-yl)-N-(2-methylimino-4-phenylthiazol-3(2H)-yl)acetamide (16a, IC50= 0.500µM) and 2-(7-benzyloxy-2-oxo-2H-chromen-4-yl)-N-[4-(4-methoxyphenyl)-2-methyliminothiazol-3(2H)-yl]acetamide (16b, IC50= 0.590µM) exhibited promising AChE inhibitory activity even better than donepezil (IC50= 0.711µM). Kinetic study for compound 5b implied mixed type inhibitor which could bind peripheral anionic site (PAS) and catalytic active site (CAS) of AChE enzyme. In addition, in vivo evaluation of compounds 5b, 13c and 16a confirmed significant memory improvement in scopolamine-induced impairment model in tested mice. Furthermore, in silico studies were performed on the synthesized compounds which included molecular docking study at the active site of recombinant human acetylcholinesterase enzyme (rhAChE) as well as prediction of ADMET and other physicochemical parameters. A correlation between the docking results and IC50 of tested compounds was routinely observed and shared similar binding pattern to the co-crystallized ligand donepezil.

Design, synthesis, and pharmacological characterization of some 2-substituted-3-phenyl-quinazolin-4(3H)-one derivatives as phosphodiesterase inhibitors.

Some 3-phenyl-quinazolin-4(3H)-one-2-thioethers (3a-e, 5a,b, 7a-e, 9a-d, 10a-d, and 12) along with 2-aminoquinazoline derivatives 13a-c were prepared and screened for their in vitro phosphodiesterase (PDE) inhibitory activity. Some compounds such as 7d,e, 9a,b,d, 10a,d, and 13b exhibited promising activity as compared with the non-selective PDE inhibitor IBMX. This inhibitory activity was validated by molecular docking in the active site of PDE7A and PDE4 to investigate their selectivity. Furthermore, the most active compound 10d (IC50 = 1.15 µM) was tested in vivo using behavioral tests. Compound 10d was able to pass the blood-brain barrier and improve scopolamine-induced cognitive deficits. Therefore, this core can be considered as a promising scaffold for further optimization to obtain new compounds with better PDE7A selective inhibition.

Synthesis and in vitro anticancer evaluation of some fused indazoles, quinazolines and quinolines as potential EGFR inhibitors.

derivatives of benzo[g]indazole 5a, b, benzo[h]quinazoline 7, 12a-c, 13a-c and 15a-c and benzo[h]quinoline 17a-c and 19a-c were synthesized from 6-methoxy-3,4-dihydronaphthalen-1(2H)-one (1). Anticancer activity of all the synthesized compounds was evaluated against four cancerous cell lines; HepG2, MCF-7, HCT116 and Caco-2. MCF-7 cells emerged as the most sensitive cell line against the target compounds. All the examined compounds, except 5a and 5b, displayed potent to moderate anticancer activity against MCF-7 cells with an IC50 values ranging from 7.21 to 21.55 µM. In particular, compounds 15c and 19b emerged as the most potent derivatives against EGFR-expressing MCF-7 cells with IC50 values = 7.70 ±â€¯0.39 and 7.21 ±â€¯0.43 µM, respectively. Additionally, both compounds did not display any significant cytotoxicity towards normal BHK-21 fibroblast cells (IC50 value > 200 µM), thereby providing a good safety profile as anticancer agents. Furthermore, compounds 15c and 19b displayed potent inhibitory activity towards EGFR in the sub-micromolar range (IC50 = 0.13 ±â€¯0.01 and 0.14 ±â€¯0.01 µM, respectively), compared to that of Erlotinib (IC50 = 0.11 ±â€¯0.01 µM). Docking studies for 15c and 19b into EGFR active site was carried out to explore their potential binding modes. Therefore, compounds 15c and 19b can be considered as interesting candidates for further development of more potent anticancer agents.

Synthesis, antitumor activity evaluation, and DNA-binding study of coumarin-based agents.

A novel series of coumarin-thiadiazole heterocycle derivatives was synthesized by the nucleophilic substitution reaction. The synthesized compounds were structurally verified by IR, 1 H NMR, 13 C NMR, mass spectra, and elemental analyses. The antitumor activity of the synthesized compounds was evaluated through DNA binding assays and the 60-cell line panel according to the US NCI-DTP protocol or a selection of human tumor cell lines: breast cancer (MCF-7), liver cancer (HepG-2), and colorectal cancer (HCT-116). Most of the compounds had better DNA/ethidium bromide fluorescence quenching rather than methyl green displacement, suggesting superior DNA intercalation over DNA groove binding. Compounds 8 and 14b showed the best quenching effect with KSV = 4.27 × 105 M-1 . Moreover, the results for compounds 8, 4c, and 4e revealed a possible dual DNA binding mode with the intercalation to be superior, with KSV 4.27 × 105 , 3.96 × 105 , and 3.51 × 105 M-1 , respectively, compared to 42%, 45%, and 43% methyl green displacement, respectively. Out of the 60-cell line panel, the leukemia HL-60 cell line was the most susceptible to growth inhibition when treated with 14a, resulting in 61% growth, followed by the lung carcinoma cell line NCI-H522 showing 67% growth when treated with 9. Moreover, compound 10c had an IC50 value of 24.9 µg/mL against the HepG-2 cell line.

Synthesis, molecular modeling studies, and anticonvulsant evaluation of novel 1-((2-hydroxyethyl)(aryl)amino)-N-substituted cycloalkanecarboxamides and their acetate esters.

A series of 1-((2-hydroxyethyl)(aryl)amino)-N-substituted cycloalkanecarboxamides IXa-l and their acetate esters Xa-l were designed and synthesized as new anticovulsant agents. The evaluation of the anticonvulsant effect was performed in vivo by subcutaneous pentylenetetrazole (scPTZ) and maximal electroshock (MES) tests in mice. Further, neurotoxicity, hepatotoxicity, and acute toxicity were determined. All the new candidates displayed 100% anticonvulsant activity in the scPTZ screen in the dose range of 0.0057-0.283 mmol/kg. The most potent compounds in the scPTZ screen were Xh (ED50 = 0.0012 mmol/kg), Xd (ED50 = 0.002 mmol/kg), Xf (ED50 = 0.004 mmol/kg), IXj (ED50 = 0.0047 mmol/kg), Xl (ED50 = 0.0076 mmol/kg), and Xi (ED50 = 0.008 mmol/kg). They exhibited higher fold activity in the anticonvulsant potential than the gold standards, phenobarbital and ethosuximide. Compound Xf was active in both scPTZ and MES screens. It showed ED50 of 0.016 mmol/kg in MES screen. In the neurotoxicity screens, none of the test compounds displayed any minimal motor impairment at the maximum administered dose. The 3D pharmacophore model using Biova 1 Discovery Studio 2016 programs exhibited high fit value. The anticonvulsant evaluation results were compatible with the molecular modeling study.

Computer-aided identification of novel anticancer compounds with a possible dual HER1/HER2 inhibition mechanism.

HER1 and HER2 are frequently overexpressed in human tumors where they drive cellular proliferation. For this reason they are considered important targets in anticancer therapy with dual HER1/HER2 inhibitors being recently approved and marketed. In this paper we report the identification of a series of compounds with anticancer activity by a combined virtual screening approach on the kinase domains of HER1 and HER2. 6 hit compounds that present a sub- or low-micromolar activity in two cell-based assays, were initially identified and a subsequent design cycle led to the synthesis of a compound with nanomolar activity in the cell-based assays.

Dual PI3K/Akt Inhibitors Bearing Coumarin-Thiazolidine Pharmacophores as Potential Apoptosis Inducers in MCF-7 Cells.

Breast cancer is the most common malignancy worldwide; therefore, the development of new anticancer agents is essential for improved tumor control. By adopting the pharmacophore hybridization approach, two series of 7-hydroxyl-4-methylcoumarin hybridized with thiosemicarbazone (V-VI) and thiazolidin-4-one moieties (VII-VIII) were prepared. The in vitro anticancer activity was assessed against MCF-7 cells adopting the MTT assay. Nine compounds showed significant cytotoxicity. The most promising compound, VIIb, induced remarkable cytotoxicity (IC50 of 1.03 + 0.05 µM). Further investigations were conducted to explore its pro-apoptotic activity demonstrating S-phase cell cycle arrest. Apoptosis rates following VIIb treatment revealed a 5-fold and 100-fold increase in early and late apoptotic cells, correspondingly. Moreover, our results showed caspase-9 dependent apoptosis induction as manifested by an 8-fold increase in caspase-9 level following VIIb treatment. Mechanistically, VIIb was found to target the PI3K-α/Akt-1 axis, as evidenced by enzyme inhibition assay results reporting significant inhibition of examined enzymes. These findings were confirmed by Western blot results indicating the ability of VIIb to repress levels of Cyclin D1, p-PI3K, and p-Akt. Furthermore, docking studies showed that VIIb has a binding affinity with the PI3K binding site higher than the original ligands X6K. Our results suggest that VIIb has pharmacological potential as a promising anti-cancer compound by the inhibition of the PI3K/Akt axis.

Design, synthesis and vasorelaxant evaluation of novel coumarin-pyrimidine hybrids.

The main objective of the present work depends on the hybridization of coumarin moiety as a vasorelaxant scaffold and pyrimidine ring with known potential cardiovascular activity in order to prepare some new potent antihypertensive candidates. Hence, two groups of pyrimidinyl coumarin derivatives were synthesized and evaluated for their vasorelaxing activity. These compounds were prepared via two routes; either preparation of the guanidinocoumarin 4 followed by a cocktail of cyclization reactions to yield a different array of 6-(substituted pyrimidin-2-yl)aminocoumarins 5-17, or through cyclization of the precursor chalcones 22a-g with guanidine hydrochloride to generate the corresponding final compounds, 8-(6-aryl-2-aminopyrimidin-4-yl)-7-methoxycoumarins 23a-g. The effect of these compounds and the coumarin intermediates 3, 4, 21 and 22a-g on nor-epinephrine induced contracture in thoracic rat aortic rings was investigated using prazocin as reference drug. Several derivatives showed promising activities either equal or even better than that of prazocin (IC(50) 0.487 mM). The most prospective compounds; the pyrimidinylamino coumarin derivatives 8, 17 (IC(50) 0.411, IC(50) 0.421 mM) and the chalcones 22b, 22e (IC(50) 0.371, 0.374 mM) that displayed the highest activity can be a base for lead optimization and simple but efficient design of new compounds. 2D-QSAR analysis was applied to find a correlation between the experimental vasorelaxant activities of the newly synthesized coumarin derivatives and their different physicochemical parameters. The result of this study showed that the increase in aqueous solubility while retaining good hydrophobic character of the overall molecule is the key for maintaining high relaxation activity.

Neurobehavioral investigation and acetylcholinesterase inhibitory activity study for some new coumarin derivatives.

Twenty four 6-aminocoumarin based derivatives were synthesized according to two schemes. All the compounds were screened for their acetylcholinesterase inhibitory activity where compound 5b proved to be the most potent AChE inhibitor with (IC50 = 37 nM) compared to tacrine and donepezil (IC50 = 55.0 and 59.0 nM, respectively). Six compounds 2f, 2g, 4b, 5b, 8b and 9b revealed superior activity over donepezil and a conclusive structure activity relationship study was conducted explaining the obtained results. Furthermore, compounds 2f, 4b and 5b were investigated for their neurobehavioral effect in vivo. All the tested compounds showed improvement of neurobehavioral experiments using donepezil as reference drug. In addition, compounds 2f, 4b and 5b were able to reduce extracellular deposition of amyloid beta 42 in a comparable manner to donepezil. The binding modes of the synthesized compounds were evaluated in silico via molecular docking in the active site of AChE, as well as molecular dynamics simulation study. A pharmacophore model was generated for the newly synthesized compounds.

Design, synthesis and molecular modeling study for some new 2-substituted benzimidazoles as dual inhibitors for VEGFR-2 and c-Met.

AIM: Computer-aided drug design techniques were adopted to design three series of 2-substituted-5-nitrobenzimidazole derivatives hybridized with piperzine 5a,b, oxadiazole 7a,b, 9, 14a-c and triazolo-thiadiazole moieties 12a-d, as VEGFR-2/c-Met kinase inhibitors. MATERIALS & METHODS: The designed compounds were synthesized adopting the chemical pathways outlined in schemes 1 and 2 to afford the desired three series followed by evaluating their inhibitory activities against VEGFR-2 and c-Met and in vitro anticancer activities. RESULT: Analogs bearing substituted phenyl ring attached to oxadiazole ring 14a showed the greatest inhibitory activities against non-small-cell lung cancer NCI-H522 and melanoma SK-MEL-2 with inhibition percent of 48.70 and 42.62, respectively. Moreover, unsubstituted phenoxymethyl derivative 12d exhibited promising inhibitory activity against VEGFR-2 and c-Met (35.88 and 88.48%), respectively. CONCLUSION: The above results revealed that 2-substituted-5-nitrobenzimidazole hybridized with various heterocyclic scaffolds could be a potential anticancer agent.

Enantioseparation of Substituted 1, 3-Diazaspiro [4.5]Decan-4-Ones: HPLC Comparative Study on Different Polysaccharide Type Chiral Stationary Phases.

Enantioseparation of substituted 1,3-diazaspiro[4.5]decan-4-ones (1-14) was achieved using different polysaccharide type chiral stationary phases (CSPs), namely, Chiralcel OJ, Chiralcel OD and Lux-Amylose-2 using different mobile phases which were either n-hexane/2-propanol or n-hexane/ethanol mixtures of various ratios (v/v) at flow rate 1 mL min-1. UV detection was carried out at 254 nm and temperature of 20°C. The retention behavior and selectivity of these CSPs were examined in isocratic normal phase high-performance liquid chromatography mode. The results revealed that the amylose CSP (Lux-Amylose-2) could separate almost all the compounds under investigation in contrast to cellulose CSPs (Chiracel OJ and Chiracel OD) which resolved fewer compounds.

Identification of new potent phthalazine derivatives with VEGFR-2 and EGFR kinase inhibitory activity.

Efforts to develop new antitumor agents are now directed towards multitarget therapies that are believed to have high potency and low tendency to resistance compared to conventional drugs. Herein, we highlighted the synthesis and antitumor activity of five series of phthalazine-based compounds featuring a variety of bioactive chemical fragments at position 1 of the phthalazine nucleus. The antitumor activity of the target compounds was performed against fourteen cancer cell lines where all compounds were active in the nanomolar level. In addition, the mechanism of action of the target compounds was investigated through an enzymatic inhibitory assay against VEGFR-2 and EGFR kinases, revealing potent and preferential activity toward VEGFR-2. Binding mode of the most active compounds was studied using docking experiment.

Synthesis and anticancer activity of some 8-substituted-7-methoxy-2H-chromen-2-one derivatives toward hepatocellular carcinoma HepG2 cells.

Based on the reported anticancer activity of coumarin and pyrazoline derivatives, the present investigation dealt with the design and synthesis of coumarin derivatives bearing diversely substituted pyrazoline moieties 7-10. The non-cyclic isosteres 11a-e of compounds 10a-e were synthesized for comparative reasons. The target compounds were synthesized from 8-acetyl-7-methoxycoumarin that underwent Claisen-Schmidt condensation with various aldehydes to give the chalcones 6a-e, followed by reaction with hydrazine hydrate, phenyl hydrazine or semicarbazide under the appropriate conditions. Cytotoxicity of the synthesized compounds was evaluated in vitro against liver HepG2 cell line. Compounds were active in the nanomolar range. The most active compounds were investigated for their telomerase inhibition and proapoptotic activities.

Small molecule inhibitors of West Nile virus.

West Nile virus (WNV) is a human pathogen which is rapidly expanding worldwide. It is a member of the Flavivirus genus and it is transmitted by mosquitos between its avian hosts and occasionally in mammalian hosts. In humans the infection is often asymptomatic, however, the most severe cases result in encephalitis or meningitis. Approximately 10% of cases of neuroinvasive disease are fatal. To date there is no effective human vaccine or effective antiviral therapy available to treat WNV infections. For this reason, research in this field is rapidly growing. In this article we will review the latest efforts in the design and development of novel WNV inhibitors from a medicinal chemistry point of view, highlighting challenges and opportunities for the researchers working in this field.

Synthesis and biological evaluation of novel coumarin-pyrazoline hybrids endowed with phenylsulfonyl moiety as antitumor agents.

Two groups of coumarin-pyrazoline hybrids were synthesized. The target compounds were obtained by cyclization of the coumarin chalcones with various substituted hydrazines to produce the corresponding pyrazolines through 1,4-addition on α,ß-unsaturated carbonyl system. Selected compounds were investigated for their anticancer activity toward 60 cancer cell lines according to US NCI protocol where breast cancer MCF7 and colon cancer HCT-116 were the most susceptible to the influence of compounds 7d, 8c and 9c. Encouraged by this, all final compounds were screened against colorectal cell line HCT-116. The tested compounds exhibited high potency with IC(50) ranging from 0.01 µM to 2.8 µM. Moreover, compound 9c which possessed the highest cytotoxicity proved to have weak enzyme inhibitory activity against PI3K (p110α/p85α).

Design and synthesis of novel stiripentol analogues as potential anticonvulsants.

A series of stiripentol (STP) analogues namely, 2-[(1E)-1-(1,3-benzodioxol-5-yl)-4,4-dimethylpent-1-en-3-ylidene]-N-(aryl/H)hydrazinecarboxamides 7a-h, (±)-(5RS)-N-(aryl/H)-(1,3-benzodioxol-5-yl)-3-tert-butyl-4,5-dihydro-1H-pyrazole-1-carboxamides (±)-8a-h, and (±)-[(5RS)-(1,3-benzodioxol-5-yl)-3-tert-butyl-4,5-dihydro-1H-pyrazol-1-yl](aryl)methanones (±)-13a-f was synthesized by adopting appropriate synthetic routes and was pharmacologically evaluated in the preliminary anticonvulsant screens. The selected bioactive new chemical entities were subjected to ED(50) determination and neurotoxicity evaluation. The most active congeners are 7h in MES screen and (±)-13b in scPTZ screen which displayed ED(50) values of 87 and 110 mg/kg, respectively, as compared to that of STP (ED(50) = 277.7 and 115 mg/kg in MES and scPTZ, respectively).

Synthesis, analgesic and anti-inflammatory activities evaluation of some bi-, tri- and tetracyclic condensed pyrimidines.

Novel series of bicyclic pyrrolo[1,2-c]pyrimidines 3a-g, 5, 6a, b, and 7a, b, tricyclic pyrimido[5,4-e]pyrrolo[1,2-c]pyrimidines 8a-c, 9a-g, 13a-c, 17, 18a, b, 19, 20a,b and 21 and tetracyclic condensed pyrimidines 14, 22 and 23 were synthesized through different chemical reactions. Structures of all synthesized pyrimidine derivatives were supported by spectral and elemental analyses. Analgesic activity evaluation was carried out using acetic acid-induced writhing assay, and all compounds exerted comparable activity to indomethacin. The anti-inflammatory activity evaluation was performed using carrageenan-induced paw edema in rats, the potency of the bicyclic derivatives 3a-f and 7b revealed comparable activity to indomethacin without gastric ulceration. The tricyclic derivatives 13a and 20a exerted good activity, however, they induced gastric ulcers while 13b and 13c showed moderate activity without ulceration. In case of tetracyclic derivatives, compound 14 exhibited the highest potency and safety profile.