Novel guanidine derivatives targeting leukemia as selective Src/Abl dual inhibitors: Design, synthesis and anti-proliferative activity.

A new series of benzene-sulfonamide derivatives 3a-i was designed and synthesized via the reaction of N-(pyrimidin-2-yl)cyanamides 1a-i with sulfamethazine sodium salt 2 as dual Src/Abl inhibitors. Spectral data IR, 1H-, 13C- NMR and elemental analyses were used to confirm the structures of all the newly synthesized compounds 3a-i and 4a-i. Crucially, we screened all the synthesized compounds 3a-i against NCI 60 cancer cell lines. Among all, compound 3b was the most potent, with IC50 of 0.018 µM for normoxia, and 0.001 µM for hypoxia, compared to staurosporine against HL-60 leukemia cell line. To verify the selectivity of this derivative, it was assessed against a panel of tyrosine kinase EGFR, VEGFR-2, B-raf, ERK, CK1, p38-MAPK, Src and Abl enzymes. Results revealed that compound 3b can effectively and selectively inhibit Src/Abl with IC500.25 µM and Abl inhibitory activity with IC500.08 µM, respectively, and was found to be more potent on these enzymes than other kinases that showed the following results: EGFR IC500.31 µM, VEGFR-2 IC500.68 µM, B-raf IC500.33 µM, ERK IC501.41 µM, CK1 IC500.29 µM and p38-MAPK IC500.38 µM. Moreover, cell cycle analysis and apoptosis performed to compound 3b against HL-60 suggesting its antiproliferative activity through Src/Abl inhibition. Finally, molecular docking studies and physicochemical properties prediction for compounds 3b, 3c, and 3 h were carried out to investigate their biological activities and clarify their bioavailability.

Design, synthesis, cytotoxic activities, and molecular docking of chalcone hybrids bearing 8-hydroxyquinoline moiety with dual tubulin/EGFR kinase inhibition.

The present study established thirteen novel 8-hydroxyquinoline/chalcone hybrids3a-mof hopeful anticancer activity. According to NCI screening and MTT assay results, compounds3d-3f, 3i,3k,and3ldisplayed potent growth inhibition on HCT116 and MCF7 cells compared to Staurosporine. Among these compounds,3eand3fshowed outstanding superior activity against HCT116 and MCF7 cells and better safety toward normal WI-38 cells than Staurosporine. The enzymatic assay revealed that3e,3d, and3ihad goodtubulin polymerization inhibition (IC50 = 5.3, 8.6, and 8.05 µM, respectively) compared to the reference Combretastatin A4 (IC50 = 2.15 µM). Moreover,3e,3l, and3fexhibited EGFR inhibition (IC50 = 0.097, 0.154, and 0.334 µM, respectively) compared to Erlotinib (IC50 = 0.056 µM). Compounds3eand3fwere investigated for their effects on the cell cycle, apoptosis induction, andwnt1/ß-cateningene suppression. The apoptosis markers Bax, Bcl2, Casp3, Casp9, PARP1, and ß-actin were detected by Western blot. In-silico molecular docking, physicochemical, and pharmacokinetic studies were implemented for the validation of dual mechanisms and other bioavailability standards. Hence, Compounds3eand3fare promising antiproliferative leads with tubulin polymerization and EGFR kinase inhibition.

Development and Assessment of 1,5-Diarylpyrazole/Oxime Hybrids Targeting EGFR and JNK-2 as Antiproliferative Agents: A Comprehensive Study through Synthesis, Molecular Docking, and Evaluation.

New 1,5-diarylpyrazole oxime hybrid derivatives (scaffolds A and B) were designed, synthesized, and then their purity was verified using a variety of spectroscopic methods. A panel of five cancer cell lines known to express EGFR and JNK-2, including human colorectal adenocarcinoma cell line DLD-1, human cervical cancer cell line Hela, human leukemia cell line K562, human pancreatic cell line SUIT-2, and human hepatocellular carcinoma cell line HepG2, were used to biologically evaluate for their in vitro cytotoxicity for all the synthesized compounds 7a-j, 8a-j, 9a-c, and 10a-c. The oxime containing compounds 8a-j and 10a-c were more active as antiproliferative agents than their non-oxime congeners 7a-j and 9a-c. Compounds 8d, 8g, 8i, and 10c inhibited EGFR with IC50 values ranging from 8 to 21 µM when compared with sorafenib. Compound 8i inhibited JNK-2 as effectively as sorafenib, with an IC50 of 1.0 µM. Furthermore, compound 8g showed cell cycle arrest at the G2/M phase in the cell cycle analysis of the Hela cell line, whereas compound 8i showed combined S phase and G2 phase arrest. According to docking studies, oxime hybrid compounds 8d, 8g, 8i, and 10c exhibited binding free energies ranging from -12.98 to 32.30 kcal/mol at the EGFR binding site whereas compounds 8d and 8i had binding free energies ranging from -9.16 to -12.00 kcal/mol at the JNK-2 binding site.

Design, synthesis, biological evaluation, and computational studies of novel thiazolo-pyrazole hybrids as promising selective COX-2 inhibitors: Implementation of apoptotic genes expression for ulcerogenic liability assessment.

A novel series of thiazolo-pyrazole hybrids has been prepared and assessed for their in vitro COX-1/COX-2 inhibitory activity. Compound 6c exhibited the most selective COX-2 inhibition profile (SI of 264) not far of Celecoxib (294). In-vivo anti-inflammatory activity revealed that compound 6d exhibited the highest activity (97.30% inhibition of edema) exceeding reference standard Indomethacin (84.62% inhibition of edema). The ulcerogenic liability tested, using gross, microscopic, biochemical analysis and apoptotic genes expression, showed that compound 6b matched the optimal candidate activity (ulcer index = 120, selectivity index of ~ 162 and 77% in-vivo inhibition of edema). Meanwhile, compound 6 m (ulcer index = 0) showcased the highest safety profile. Molecular modeling analysis and drug likeness studies presented appreciated agreement with the biological evaluation.

Design and synthesis of pyrimidine-5-carbonitrile hybrids as COX-2 inhibitors: Anti-inflammatory activity, ulcerogenic liability, histopathological and docking studies.

Two new series of 1,3,4-oxadiazole and coumarin derivatives based on pyrimidine-5-carbonitrile scaffold have been synthesized and evaluated for their COX-1/COX-2 inhibitory activity. Compounds 10c, 10e, 10h-j, 14e-f, 14i and 16 were found to be the most potent and selective inhibitors of COX-2 (IC50 0.041-0.081 µM, SI 139.74-321.95). Eight compounds were further investigated for their in vivo anti-inflammatory activity. The most active derivatives 10c, 10j and 14e displayed superior in vivo anti-inflammatory activity (% edema inhibition 39.3-48.3, 1 h; 58.4-60.5, 2 h; 70.8-83.2, 3 h; 78.9-89.5, 4 h) to the reference drug celecoxib (% edema inhibition 38.0, 1 h; 48.8, 2 h; 58.4, 3 h; 65.4, 4 h). These derivatives were also tested for their ulcerogenic liability, compound 10j showed better safety profile with reference to celecoxib while 10c and 14e exhibited mild lesions. Molecular docking studies of 10c, 10j, and 14e in the COX-2 active site revealed similar orientation and binding interactions as selective COX-2 inhibitors with a higher liability to access the selectivity side pocket.

Daptomycin: A Novel Macrocyclic Antibiotic as a Chiral Selector in an Organic Polymer Monolithic Capillary for the Enantioselective Analysis of a Set of Pharmaceuticals.

Daptomycin, a macrocyclic antibiotic, is here used as a new chiral selector in preparation of chiral stationary phase (CSP) in a recently prepared polymer monolithic capillary. The latter is prepared using the copolymerization of the monomers glycidyl methacrylate (GMA) and ethylene glycol dimethacrylate (EGDMA) in the presence of daptomycin in water. Under reversed phase conditions (RP), the prepared capillaries were tested for the enantioselective nanoliquid chromatographic separation of fifty of the racemic drugs of different pharmacological groups, such as adrenergic blockers, H1-blockers, NSAIDs, antifungal drugs, and others. Baseline separation was attained for many drugs under RP-HPLC. Daptomycin expands the horizon of chiral selectors in HPLC.

Design, Synthesis, Biological Evaluation, and Computational Studies of Novel Tri-Aryl Imidazole-Benzene Sulfonamide Hybrids as Promising Selective Carbonic Anhydrase IX and XII Inhibitors.

A novel series of tri-aryl imidazole derivatives 5a-n carrying benzene sulfonamide moiety has been designed for their selective inhibitory against hCA IX and XII activity. Six compounds were found to be potent and selective CA IX inhibitors with the order of 5g > 5b > 5d > 5e > 5g > 5n (Ki = 0.3-1.3 µM, and selectivity ratio for hCA IX over hCA XII = 5-12) relative to acetazolamide (Ki = 0.03 µM, and selectivity ratio for hCA IX over hCA XII = 0.20). The previous sixth inhibitors have been further investigated for their anti-proliferative activity against four different cancer cell lines using MTT assay. Compounds 5g and 5b demonstrated higher antiproliferative activity than other tested compounds (with GI50 = 2.3 and 2.8 M, respectively) in comparison to doxorubicin (GI50 = 1.1 M). Docking studies of these two compounds adopted orientation and binding interactions with a higher liability to enter the active side pocket CA-IX selectively similar to that of ligand 9FK. Molecular modelling simulation showed good agreement with the acquired biological evaluation.

Synthesis, DFT Calculations, Antiproliferative, Bactericidal Activity and Molecular Docking of Novel Mixed-Ligand Salen/8-Hydroxyquinoline Metal Complexes.

Despite the common use of salens and hydroxyquinolines as therapeutic and bioactive agents, their metal complexes are still under development. Here, we report the synthesis of novel mixed-ligand metal complexes (MSQ) comprising salen (S), derived from (2,2'-{1,2-ethanediylbis[nitrilo(E) methylylidene]}diphenol, and 8-hydroxyquinoline (Q) with Co(II), Ni(II), Cd(II), Al(III), and La(III). The structures and properties of these MSQ metal complexes were investigated using molar conductivity, melting point, FTIR, 1H NMR, 13C NMR, UV-VIS, mass spectra, and thermal analysis. Quantum calculation, analytical, and experimental measurements seem to suggest the proposed structure of the compounds and its uncommon monobasic tridentate binding mode of salen via phenolic oxygen, azomethine group, and the NH group. The general molecular formula of MSQ metal complexes is [M(S)(Q)(H2O)] for M (II) = Co, Ni, and Cd or [M(S)(Q)(Cl)] and [M(S)(Q)(H2O)]Cl for M(III) = La and Al, respectively. Importantly, all prepared metal complexes were evaluated for their antimicrobial and anticancer activities. The metal complexes exhibited high cytotoxic potency against human breast cancer (MDA-MB231) and liver cancer (Hep-G2) cell lines. Among all MSQ metal complexes, CoSQ and LaSQ produced IC50 values (1.49 and 1.95 µM, respectively) that were comparable to that of cisplatin (1.55 µM) against Hep-G2 cells, whereas CdSQ and LaSQ had best potency against MDA-MB231 with IC50 values of 1.95 and 1.43 µM, respectively. Furthermore, the metal complexes exhibited significant antimicrobial activities against a wide spectrum of both Gram-positive and -negative bacterial and fungal strains. The antibacterial and antifungal efficacies for the MSQ metal complexes, the free S and Q ligands, and the standard drugs gentamycin and ketoconazole decreased in the order AlSQ > LaSQ > CdSQ > gentamycin > NiSQ > CoSQ > Q > S for antibacterial activity, and for antifungal activity followed the trend of LaSQ > AlSQ > CdSQ > ketoconazole > NiSQ > CoSQ > Q > S. Molecular docking studies were performed to investigate the binding of the synthesized compounds with breast cancer oxidoreductase (PDB ID: 3HB5). According to the data obtained, the most probable coordination geometry is octahedral for all the metal complexes. The molecular and electronic structures of the metal complexes were optimized theoretically, and their quantum chemical parameters were calculated. PXRD results for the Cd(II) and La(III) metal complexes indicated that they were crystalline in nature.

Design, synthesis and antiproliferative evaluation of new tricyclic fused thiazolopyrimidines targeting topoisomerase II: Molecular docking and apoptosis inducing activity.

A novel series of thiazolopyrimidines and fused thiazolopyrimidines was designed and synthesized as topoisomerase II alpha inhibitors. All synthesized compounds were screened by the National Cancer Institute (NCI), Bethesda, USA for anticancer activity against 60 human cancer cell lines representing the following cancer types: leukemia, non-small cell lung, colon, CNS, melanoma, ovarian, renal, prostate, and breast cancers. Compound 3a was found to be the most potent inhibitor on renal cell line (A-498) causing 83.03% inhibition (IC50 = 1.89 µM). DNA-flow cytometric analysis showed that compound 3a induce cell cycle arrest at G2/M phase leading to cell proliferation inhibition and apoptosis. Moreover, fused thiazolopyrimidines 3a showed potent topoisomerase II inhibitory activity (IC50 = 3.19 µM) when compared with reference compound doxorubicin (IC50 = 2.67 µM). Docking study of all the synthesized compounds showed that compound 3a interacts in a similar pattern to etoposide and stabilizing the topoisomerase cleavage complex (Top2-cc) that accounts for its high potency.

Design and synthesis of new 1,6-dihydropyrimidin-2-thio derivatives targeting VEGFR-2: Molecular docking and antiproliferative evaluation.

A series of new 1,6-dihydropyrimidin-2-thiol derivatives (scaffold A) as VEGFR-2 inhibitors has been designed and synthesized. Compounds 3a, 3b, 3e and 4b have been selected for in vitro anticancer screening by the National Cancer Institute. Compound 3e showed remarkable anticancer activity against most of the cell lines tested, where a complete cell death against leukemia, non-small cell lung cancer, colon, CNS, melanoma, and breast cancer cell lines was observed. In vitro five dose tests showed that compound 3e had high activity against most of the tested cell lines with GI50 ranging from 19 to 100 µM and selectivity ratios ranging between 0.75 and 1.71 at the GI50 level. VEGFR-2-kinase was tested against 3a, 3b, 3e, 4b and sorafenib was used as a reference. Compounds 3a and 3e were the most potent analogues with IC50 values of 386.4 nM and 198.7 nM against VEGFR-2, respectively, in comparison to sorafenib (IC50 = 0.17 nM). The results of the docking study showed a good fitting of the new compounds to the active site of VEGFR-2 with binding free energies in the range of -9.80 to -11.25 kcal/mol compared to -12.12 kcal/mol for sorafenib. Compounds 4a-e with the hydroxyimino group had a higher affinity to VEGFR-2 than their parent derivatives 3a-e.

Design, synthesis and molecular modeling of novel aryl carboximidamides and 3-aryl-1,2,4-oxadiazoles derived from indomethacin as potent anti-inflammatory iNOS/PGE2 inhibitors.

The development of NSAIDs/iNOS inhibitor hybrids is a new strategy for the treatment of inflammatory diseases by suppression of the overproduction of PGE2 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 IC50 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 IC50 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.

Design, synthesis and antitrypanosomal activity of heteroaryl-based 1,2,4-triazole and 1,3,4-oxadiazole derivatives.

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.

Design, synthesis and anticonvulsant activity of new imidazolidindione and imidazole derivatives.

New imidazolidindiones and tetra-substituted imidazole derivatives were designed, synthesized, and evaluated for the anticonvulsant activity through pentylenetetrazole (PTZ)-induced seizures and maximal electroshock (MES) tests using valproate sodium and phenytoin sodium as reference drugs, respectively. Most of the target compounds showed excellent activity against pentylenetetrazole (PTZ)-induced seizures with fair to no-activity against MES. Compounds 3d, 4e, 11b, and 11e showed higher activity (120%) than that of valproate sodium in PTZ model. Almost all compounds showed no neurotoxicity, as indicated by the rotarod test. Estimation of physicochemical properties and pharmacokinetic profiles of the target compounds were studied. The chemical structures of the target compounds were characterized by different spectrometric methods and elemental analysis.

Tailored Tetrasubstituted Imidazole Carrying the Benzenesulfonamide Fragments as Selective Human Carbonic Anhydrase IX/XII Inhibitors.

A new series of tetrasubstituted imidazole carrying sulfonamide as zinc-anchoring group has been designed. The structures of the synthesized derivatives 5 a-l have been confirmed by spectroscopic analysis. These compounds incorporate an ethylenic spacer between the benzenesulfonamide and the rest of the trisubstituted imidazole moiety and were tested as inhibitors of carbonic anhydrases and for in-vitro cytotoxicity. Most of them act as effective inhibitors of the tumor-linked CA isoforms IX and XII, in nanomolar range. Also, different compounds have shown selectivity in comparable with the standard acetazolamide. Our IBS 5 d, 5 g, and 5 l (with Ki: 10.1, 19.4, 19.8 nM against hCA IX and 47, 45, 20 nM against hCA IX) showed the best inhibitory profile. In-vitro screening of all derivatives against a full sixty-cell-lined from NCI at a single dose of 10 µM offered growth inhibition of up to 45 %. Compound 5 b has been identified with the most potent cytotoxic activity and broad spectrum. Docking studies have also been implemented and were also in accordance with the biological outcomes. Our SAR analysis has interestingly proposed efficient tumor-related hCAs IX/XII suppression.

2-(4-Chloro-phen-yl)-1-pentyl-4,5-di-phenyl-1H-imidazole.

In the title compound, C26H25ClN2, the phenyl rings and the 2-(4-chloro-phen-yl) group make dihedral angles of 30.03 (11), 67.49 (12) and 41.56 (11)°, respectively, with the imidazole ring. In the crystal, the mol-ecules inter-act with each other via very weak C-H⋯π contacts, forming layers parallel to (110).

2-(2,5-Di-meth-oxy-phen-yl)-4,5-diphenyl-1-(prop-2-en-1-yl)-1H-imidazole.

In the title compound, C26H24N2O2, the two phenyl and the 2,5-di-meth-oxy-phen-yl rings are inclined to the imidazole ring at dihedral angles of 30.38 (8), 56.59 (9) and 73.11 (9)°, respectively. In the crystal, mol-ecules are linked by pairs of C-H⋯O inter-actions into centrosymmetric dimers with graph-set notation R 2 (2)(8). C-H⋯π inter-actions are also observed.

Prop-2-en-1-yl 4-(4,5-diphenyl-1H-imidazol-2-yl)benzoate.

The title compound, C25H20N2O2, crystallized with two mol-ecules in the asymmetric unit, in one of which the atoms of the terminal propenyl group are disordered over two sets of sites, with a refined occupancy ratio of 0.870 (4):0.130 (4). The central imidazole ring makes dihedral angles of 25.51 (11), 40.73 (11) and 27.36 (11)° with the three pendant rings in one molecule and 22.56 (10), 60.72 (10) and 5.85 (10)° in the other. In the crystal, mol-ecules are linked by N-H⋯N and C-H⋯O hydrogen bonds, forming a three-dimensional network. The crystal structure also features C-H⋯π inter-actions and π-π stacking [centroid-centroid distances = 3.8834 (18) and 3.9621 (17) Å] inter-actions.

2-(4-Bromo-phen-yl)-1-pentyl-4,5-diphenyl-1H-imidazole.

The title compound, C26H25BrN2, is isomorphous with the chloro derivative [2-(4-chloro-phen-yl)-1-pentyl-4,5-diphenyl-1H-imidazole; Mohamed et al. (2013 ▶). Acta Cryst. E69, o846-o847]. The two phenyl rings and the 4-bromo-phenyl ring are oriented at dihedral angles of 30.1 (2), 64.3 (3) and 42.0 (2)°, respectively, with respect to the imidazole ring. In the crystal, mol-ecules stack in columns along the b-axis direction, however, there are no significant inter-molecular inter-actions present.

2-(3,4-Di-meth-oxy-phen-yl)-1-pentyl-4,5-diphenyl-1H-imidazole.

The central imidazole ring in the title compound, C28H30N2O2, makes dihedral angles of 28.42 (13), 71.22 (15) and 29.50 (14)°, respectively, with the phenyl rings in the 4- and 5-positions and the 3,4-di-meth-oxy-phenyl group. In the crystal, mol-ecules are linked by C-H⋯O and C-H⋯N hydrogen bonds, weak π-π stacking inter-actions [centroid-centroid distance = 3.760 (2) Å] and C-H⋯π contacts, forming a three-dimensional network.

14-Bromo-12-chloro-2,16-dioxa-penta-cyclo-[7.7.5.0(1,21).0(3,8).0(10,15)]henicosa-3(8),10,12,14-tetra-ene-7,20-dione.

In the title compound, C19H16BrClO4, both the fused xanthene rings and one of the cyclo-hexane rings adopt envelope conformations, while the other cyclo-hexane ring is in a chair conformation. In the crystal, mol-ecules are linked by C-H⋯O hydrogen bonds, forming infinite chains running along [10-1] incorporating R 2 (2)(16) ring motifs. In addition, C-H⋯π inter-actions and weak π-π stacking inter-actions [centroid-centroid distance = 3.768 (3) Å] help to consolidate the packing.