1,2,4-Triazole/oxime hybrids as new strategy for nitric oxide donors: Synthesis, anti-inflammatory, ulceroginicity and antiproliferative activities

Design, synthesis, and antiproliferative activity of new indole/1,2,4-triazole/chalcone hybrids as EGFR and/or c-MET inhibitors

A novel group of indolyl-1,2,4-triazole-chalcone hybrids was designed, synthesized, and assessed for their anticancer activity. The synthesized compounds exhibited significant antiproliferative activity. Compounds 9a and 9e exhibited significant cancer inhibition with GI50 ranging from 3.69 to 20.40 µM and from 0.29 to >100 µM, respectively. Both compounds displayed a broad spectrum of anticancer activity with selectivity ratios ranging between 0.50-2.78 and 0.25-2.81 at the GI50 level, respectively. The synthesized compounds were also screened for their cytotoxicity by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazol (MTT) assay and for inhibition of epidermal growth factor receptor (EGFR) and c-MET (mesenchymal-epithelial transition factor). Some of the tested compounds exhibited significant inhibition against EGFR and/or c-MET. Compound 9b showed the highest c-MET inhibition (IC50 = 4.70 nM) compared to foretinib (IC50 = 2.5 nM). Compound 9d showed equipotent activity compared with erlotinib against EGFR (IC50 = 0.052 µM) and displayed significant c-MET inhibition with an IC50 value of 4.90 nM.

Significance of Triazole in Medicinal Chemistry: Advancement in Drug Design, Reward and Biological Activity

One of the triazole tautomers, 1,2,4-triazole derivatives, has a wide range of biological activities that suggest its potential therapeutic utility in medicinal chemistry. These actions include anti-inflammatory, anti-cancer, anti-bacterial, anti-tuberculosis, and anti-diabetic effects. Using computational simulations and models, we investigate the structure-activity relationships of 1,2,4-triazoles, showing how various modifications to the triazole core yield a variety of clinical therapeutic benefits. The review highlights the anti-inflammatory effect of 1,2,4-triazoles in relation to their ability to disrupt significant inflammatory mediators and pathways. We present in-silico data that illuminate the triazoles' capacity to inhibit cell division, encourage apoptosis, and stop metastasis in a range of cancer models. This review looks at the bactericidal and bacteriostatic properties of 1,2,4-triazole derivatives, with a focus on their potential efficacy against multi-drug resistant bacterial infections and their usage in tuberculosis therapy. In order to better understand these substances' potential anti-diabetic benefits, this review also looks at how they affect glucose metabolism regulation and insulin responsiveness. Coordinated efforts are required to translate the efficacy of 1,2,4-triazole compounds in preclinical models into practical therapeutic benefits. Based on the information provided, it can be concluded that 1,2,4-triazole derivatives are a promising class of diverse therapeutic agents with potential utility in a range of disorders. Their development and improvement might herald a new era of medical care that will be immensely advantageous to both patients and the medical community as a whole. This comprehensive research, which is further reinforced by in-silico investigations, highlights the great medicinal potential of 1,2,4-triazoles. Additionally, this study encourages more research into these substances and their enhancement for use in pharmaceutical development.

Exploring theophylline-1,2,4-triazole tethered N-phenylacetamide derivatives as antimicrobial agents: unraveling mechanisms via structure-activity relationship, in vitro validation, and in silico insights

Theophylline, a nitrogen-containing heterocycle, serves as a promising focal point for medicinal researchers aiming to create derivatives with diverse pharmacological applications. In this work, we present an improved synthetic method for a range of theophylline-1,2,4-triazole-S-linked N-phenyl acetamides (4a‒g) utilizing ultrasound-assisted synthetic approach. The objective was to assess the effectiveness of synthesized theophylline-1,2,4-triazoles (4a‒g) as inhibitors of HCV serine protease and as antibacterial agents against B. subtilis QB-928 and E. coli AB-274. Theophylline-1,2,4-triazoles were obtained in good to excellent yields (69%-95%) in a shorter time than conventional approach. 4-Chlorophenyl moiety containing theophylline-1,2,4-triazole 4c displayed significantly higher inhibitory activity against HCV serine protease enzyme (IC50 = 0.015 ± 0.25 mg) in comparison to ribavirin (IC50 = 0.165 ± 0.053 mg), but showed excellent binding affinity (-7.55 kcal/mol) with the active site of serine protease, better than compound 4c (-6.90 kcal/mol) as well as indole-based control compound 5 (-7.42 kcal/mol). In terms of percentage inhibition of serine protease, 2-chlorophenyl compound 4b showed the maximum percentage inhibition (86%), more than that of the 3,4-dichlorophenyl compound 4c (76%) and ribavirin (81%). 3,4-Dimethylphenyl-based theophylline-1,2,4-triazole 4g showed the lowest minimum inhibitory concentration (MIC = 0.28 ± 0.50 μg/mL) against the B. subtilis bacterial strain as compared to the standard drug penicillin (MIC = 1 ± 1.50 μg/mL). The other 4-methylphenyl theophylline-1,2,4-triazole 4e (MIC = 0.20 ± 0.08 μg/mL) displayed the most potent antibacterial potential against E. coli in comparison to the standard drug penicillin (MIC = 2.4 ± 1.00 μg/mL). Molecular docking studies further helped in an extensive understanding of all of the interactions between compounds and the enzyme active site, and DFT studies were also employed to gain insights into the molecular structure of the synthesized compounds. The results indicated that theophylline-linked triazole derivatives 4b and 4c showed promise as leading contenders in the fight against the HCV virus. Moreover, compounds 4e and 4g demonstrated potential as effective chemotherapeutic agents against E. coli and B. subtilis, respectively. To substantiate these findings, additional in vivo studies and clinical trials are imperative, laying the groundwork for their integration into future drug design and development.

Synthesis, characterization, X-ray, α-glucosidase inhibition and molecular docking study of new triazolic systems based on 1,5-benzodiazepine via 1,3-dipolar cycloaddition reactions

We report in this work a synthesis of novel triazolo[1,5]benzodiazepine derivatives by the 1,3-dipolar cycloaddition reaction of N-aryl-C-ethoxycarbonylnitrilimines with 1,5-benzodiazepines. All the structures of the new compounds were determined from their NMR (1H and 13C) and HRMS. Then, X-ray crystallography analysis of compound 4d confirmed the stereochemistry of cycloadducts. The compounds 1, 4a-d, 5a-d, 6c, 7 and 8 were evaluated for their in vitro anti-diabetic activity against α-glucosidase. The compounds 1, 4d, 5a and 5b showed potential inhibitory activities compared to standard acarbose. Additionally, an in silico docking study was conducted to look into the active binding mode of the synthesized compounds within the target enzyme.Communicated by Ramaswamy H. Sarma.

New 1,2,3-triazole/1,2,4-triazole hybrids linked to oxime moiety as nitric oxide donor selective COX-2, aromatase, B-RAFV600E and EGFR inhibitors celecoxib analogs: design, synthesis, anti-inflammatory/anti-proliferative activities, apoptosis and molecular modeling study

A new series of bis-triazole 19a-l was synthesised for the purpose of being hybrid molecules with both anti-inflammatory and anti-cancer activities and assessed for cell cycle arrest, NO release. Compounds 19c, 19f, 19h, 19 l exhibited COX-2 selectivity indexes in the range of 18.48 to 49.38 compared to celecoxib S.I. = 21.10), inhibit MCF-7 with IC50 = 9-16 μM compared to tamoxifen (IC50 = 27.9 μM). and showed good inhibitory activity against HEP-3B with IC50 = 4.5-14 μM compared to sorafenib (IC50 = 3.5 μM) (HEP-3B). Moreover, derivatives 19e, 19j, 19k, 19 l inhibit HCT-116 with IC50 = 5.3-13.7 μM compared to 5-FU with IC50 = 4.8 μM (HCT-116). Compounds 19c, 19f, 19h, 19 l showed excellent inhibitory activity against A549 with IC50 = 3-4.5 μM compared to 5-FU with IC50 = 6 μM (A549). Compounds 19c, 19f, 19h, 19 l inhibit aromatase (IC50 of 22.40, 23.20, 22.70, 30.30 μM), EGFR (IC50 of 0.112, 0.205, 0.169 and 0.066 μM) and B-RAFV600E (IC50 of 0.09, 0.06, 0.07 and 0.05 μM).

New pyrazolyl-thiazolidinone/thiazole derivatives as celecoxib/dasatinib analogues with selective COX-2, HER-2 and EGFR inhibitory effects: design, synthesis, anti-inflammatory/anti-proliferative activities, apoptosis, molecular modelling and ADME studies

Two new series of pyrazolyl-thiazolidinone/thiazole derivatives 16a-b and 18a-j were synthesised, merging the scaffolds of celecoxib and dasatinib. Compounds 16a, 16b and 18f inhibit COX-2 with S.I. 134.6, 26.08 and 42.13 respectively (celecoxib S.I. = 24.09). Compounds 16a, 16b, 18c, 18d and 18f inhibit MCF-7 with IC50 = 0.73-6.25 μM (dasatinib IC50 = 7.99 μM) and (doxorubicin IC50 = 3.1 μM) and inhibit A549 with IC50 = 1.64-14.3 μM (dasatinib IC50 = 11.8 μM and doxorubicin IC50 = 2.42 μM) with S.I. (F180/MCF7) of 33.15, 7.13, 18.72, 13.25 and 8.28 respectively higher than dasatinib (4.03) and doxorubicin (3.02) and S.I. (F180/A549) of 14.75, 12.96, 4.16, 7.07 and 18.88 respectively higher than that of dasatinib (S.I. = 2.72) and doxorubicin (S.I = 3.88). Derivatives 16a, 18c, 18d, 18f inhibit EGFR and HER-2 IC50 for EGFR of 0.043, 0.226, 0.388, 0.19 μM respectively and for HER-2 of 0.032, 0.144, 0.195, 0.201 μM respectively.

The Fundamental Role of Oxime and Oxime Ether Moieties in Improving the Physicochemical and Anticancer Properties of Structurally Diverse Scaffolds

The present review explores the critical role of oxime and oxime ether moieties in enhancing the physicochemical and anticancer properties of structurally diverse molecular frameworks. Specific examples are carefully selected to illustrate the distinct contributions of these functional groups to general strategies for molecular design, modulation of biological activities, computational modeling, and structure-activity relationship studies. An extensive literature search was conducted across three databases, including PubMed, Google Scholar, and Scifinder, enabling us to create one of the most comprehensive overviews of how oximes and oxime ethers impact antitumor activities within a wide range of structural frameworks. This search focused on various combinations of keywords or their synonyms, related to the anticancer activity of oximes and oxime ethers, structure-activity relationships, mechanism of action, as well as molecular dynamics and docking studies. Each article was evaluated based on its scientific merit and the depth of the study, resulting in 268 cited references and more than 336 illustrative chemical structures carefully selected to support this analysis. As many previous reviews focus on one subclass of this extensive family of compounds, this report represents one of the rare and fully comprehensive assessments of the anticancer potential of this group of molecules across diverse molecular scaffolds.

KinomeMETA: meta-learning enhanced kinome-wide polypharmacology profiling

Kinase inhibitors are crucial in cancer treatment, but drug resistance and side effects hinder the development of effective drugs. To address these challenges, it is essential to analyze the polypharmacology of kinase inhibitor and identify compound with high selectivity profile. This study presents KinomeMETA, a framework for profiling the activity of small molecule kinase inhibitors across a panel of 661 kinases. By training a meta-learner based on a graph neural network and fine-tuning it to create kinase-specific learners, KinomeMETA outperforms benchmark multi-task models and other kinase profiling models. It provides higher accuracy for understudied kinases with limited known data and broader coverage of kinase types, including important mutant kinases. Case studies on the discovery of new scaffold inhibitors for membrane-associated tyrosine- and threonine-specific cdc2-inhibitory kinase and selective inhibitors for fibroblast growth factor receptors demonstrate the role of KinomeMETA in virtual screening and kinome-wide activity profiling. Overall, KinomeMETA has the potential to accelerate kinase drug discovery by more effectively exploring the kinase polypharmacology landscape.

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.

Synthesis, biological evaluation, and molecular modeling studies of acetophenones-tethered 1,2,4-triazoles and their oximes as epidermal growth factor receptor inhibitors

A series of 5-(4-pyridyl)-1,2,4-triazoles hybrids with acetophenones and their oxime derivatives was rationally designed and synthesized as epidermal growth factor receptor (EGFR) kinase inhibitors. Initially, drug Likeness and pharmacokinetics properties of the prepared compounds were evaluated. Afterward, the prepared compounds were in vitro screened for their ability to inhibit the growth of the NCI-60 human cancer cell lines where certain compounds showed moderate activity. Compounds 4e and 5b emerged as the most potent compounds in this series were further tested for their EGFR enzyme inhibition activity. They showed IC₅₀ values of 0.14 and 0.18 µM, respectively, in comparison with Gefitinib as a reference with an IC₅₀ value of 0.06 µM. Docking of compounds 4e and 5b into the binding site of EGFR tyrosine kinase was performed to explains their possible binding mode and to compare it with known inhibitors. Moreover, molecular dynamic simulations were estimated for deeper understanding of the binding mode of compounds 4e and 5b at the binding site of EGFR tyrosine kinase. The findings indicated that the novel ligands 4e and 5b were stable in the EGFR tyrosine kinase active site.

Thioethers: An Overview

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Spreading rapidly in recent years, cancer has become one of the causes of the highest mor-tality rates after cardiovascular diseases. The reason for cancer development is still not clearly under-stood despite enormous research activities in this area. Scientists are now working on the biology of cancer, especially on the root cause of cancer development. The aim is to treat the cancer disease and thus cure the patients. The continuing efforts for the development of novel molecules as potential anti-cancer agents are essential for this purpose. The main aim of this review was to present a survey on the medicinal chemistry of thioethers and provide practical data on their cytotoxicities against various cancer cell lines. The research articles published between 2001-2020 were consulted to pre-pare this review article; however, patent literature has not been included. The thioether-containing heterocyclic compounds may emerge as a new class of potent and effective anti-cancer agents in the future.

Discovery of ( ±)-3-(1H-pyrazol-1-yl)-6,7-dihydro-5H-[1,2,4]triazolo[3,4-b][1,3,4] thiadiazine derivatives with promising in vitro anticoronavirus and antitumoral activity

A new series of ( ±)-(3-(3,5-dimethyl-1H-pyrazol-1-yl)-6-phenyl-6,7-dihydro-5H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-7-yl)(phenyl)methanones were efficiently synthesized starting from 4-amino-5-hydrazinyl-4H-1,2,4-triazole-3-thiol 1, acetyl acetone 2, various aromatic and heterocyclic aldehydes 3 and phenacyl bromides 4. All the newly synthesized compounds were tested for their antiviral and antitumoral activity. It was shown that subtle structural variations on the phenyl moiety allowed to tune biological properties toward antiviral or antitumoral activity. Mode-of-action studies revealed that the antitumoral activity was due to inhibition of tubulin polymerization.

A first-in-class anticancer dual HDAC2/FAK inhibitors bearing hydroxamates/benzamides capped by pyridinyl-1,2,4-triazoles

Novel 5-pyridinyl-1,2,4-triazoles were designed as dual inhibitors of histone deacetylase 2 (HDAC2) and focal adhesion kinase (FAK). Compounds 5d, 6a, 7c, and 11c were determined as potential inhibitors of both HDAC2 (IC₅₀ = 0.09-1.40 μM) and FAK (IC₅₀ = 12.59-36.11 nM); 6a revealed the highest activity with IC₅₀ values of 0.09 μM and 12.59 nM for HDAC2 and FAK, respectively. Compound 6a was superior to reference drugs vorinostat and valproic acid in its ability to inhibit growth/proliferation of A-498 and Caki-1 renal cancer cells. Further investigation proved that 6a strongly arrests the cell cycle at the G2/M phase and triggers apoptosis in both A-498 and Caki-1 cells. Moreover, the enhanced Akt activity that is observed upon chronic application of HDAC inhibitors was effectively suppressed by the dual HDAC2/FAK inhibitor. Finally, the high potency and selectivity of 6a towards HDAC2 and FAK proteins were rationalized by molecular docking. Taken together, these findings highlight the potential of 6a as a promising dual-acting HDAC2/FAK inhibitor that could benefit from further optimization.

Novel (+)-Neoisopulegol-Based O-Benzyl Derivatives as Antimicrobial Agents

Discovery of novel antibacterial agents with new structures, which combat pathogens is an urgent task. In this study, a new library of (+)-neoisopulegol-based O-benzyl derivatives of aminodiols and aminotriols was designed and synthesized, and their antimicrobial activity against different bacterial and fungal strains were evaluated. The results showed that this new series of synthetic O-benzyl compounds exhibit potent antimicrobial activity. Di-O-benzyl derivatives showed high activity against Gram-positive bacteria and fungi, but moderate activity against Gram-negative bacteria. Therefore, these compounds may serve a good basis for antibacterial and antifungal drug discovery. Structure-activity relationships were also studied from the aspects of stereochemistry of the O-benzyl group on cyclohexane ring and the substituent effects on the ring system.

Oximes: Novel Therapeutics with Anticancer and Anti-Inflammatory Potential

Oximes have been studied for decades because of their significant roles as acetylcholinesterase reactivators. Over the last twenty years, a large number of oximes have been reported with useful pharmaceutical properties, including compounds with antibacterial, anticancer, anti-arthritis, and anti-stroke activities. Many oximes are kinase inhibitors and have been shown to inhibit over 40 different kinases, including AMP-activated protein kinase (AMPK), phosphatidylinositol 3-kinase (PI3K), cyclin-dependent kinase (CDK), serine/threonine kinases glycogen synthase kinase 3 α/β (GSK-3α/β), Aurora A, B-Raf, Chk1, death-associated protein-kinase-related 2 (DRAK2), phosphorylase kinase (PhK), serum and glucocorticoid-regulated kinase (SGK), Janus tyrosine kinase (JAK), and multiple receptor and non-receptor tyrosine kinases. Some oximes are inhibitors of lipoxygenase 5, human neutrophil elastase, and proteinase 3. The oxime group contains two H-bond acceptors (nitrogen and oxygen atoms) and one H-bond donor (OH group), versus only one H-bond acceptor present in carbonyl groups. This feature, together with the high polarity of oxime groups, may lead to a significantly different mode of interaction with receptor binding sites compared to corresponding carbonyl compounds, despite small changes in the total size and shape of the compound. In addition, oximes can generate nitric oxide. This review is focused on oximes as kinase inhibitors with anticancer and anti-inflammatory activities. Oximes with non-kinase targets or mechanisms of anti-inflammatory activity are also discussed.

A review of the synthesis of nitric oxide donor and donor derivatives with pharmacological activities

Endogenous nitric oxide (NO) is an important effector molecule and signal transduction molecule, which participates in the regulation of multiple functions in organisms, involving a variety of physiological and pathological processes, especially playing a very important role in the cardiovascular, immune, and nervous systems. NO is a gaseous substance with a short half-life in the body and is unstable in aqueous solutions. Therefore, many researchers focus on the release and activity of NO donors and their derivatives. However, NO donors can release free NO or NO analogues under physiological conditions to meet the human need. NO donors can be coupled with the corresponding active basic nucleus, so that they have the biological activity derived from both the basic nucleus and the NO donors, thus performing better bioactivity. This paper reviewed the routes of synthesis and advance activities of NO donor derivatives.

An insight on medicinal attributes of 1,2,4-triazoles

The present review aims to summarize the pharmacological profile of 1,2,4-triazole, one of the emerging privileged scaffold, as antifungal, antibacterial, anticancer, anticonvulsant, antituberculosis, antiviral, antiparasitic, analgesic and anti-inflammatory agents, etc. along with structure-activity relationship. The comprehensive compilation of work carried out in the last decade on 1,2,4-triazole nucleus will provide inevitable scope for researchers for the advancement of novel potential drug candidates having better efficacy and selectivity.

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.

Hassan A, Makhlouf MM, Bräse S. Chemistry and Biological Activities of 1,2,4-Triazolethiones-Antiviral and Anti-Infective Drugs

Mercapto-substituted 1,2,4-triazoles are very interesting compounds as they play an important role in chemopreventive and chemotherapeutic effects on cancer. In recent decades, literature has been enriched with sulfur- and nitrogen-containing heterocycles which are used as a basic nucleus of different heterocyclic compounds with various biological applications in medicine and also occupy a huge part of natural products. Therefore, we shed, herein, more light on the synthesis of this interesting class and its application as a biologically active moiety. They might also be suitable as antiviral and anti-infective 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.

Synthesis and biological evaluation of novel xanthine derivatives as potential apoptotic antitumor agents

A series of novel xanthine/NO donor hybrids containing 1,3,8-trisubstituted or 1,8-disubstituted xanthine derivatives were designed and synthesized. The synthesized compounds were tested in a cell viability assay using human mammary gland epithelial cell line (MCF-10A) where all the compounds exhibited no cytotoxic effects and more than 90% cell viability at a concentration of 50 μM. The oxime containing compounds 7a-b and 17-24 were more active as antiproliferative agents than their non-oxime congeners 6a-b and 9-16. Hydroxyimino-phenethyl scaffold compounds 17-24 were more active than the hydroxyimino-ethyl phenyl acetamide 7a-b derivatives. Compounds 18-20 and 22-24 exhibited inhibition of EGFR with IC₅₀ ranging from 0.32 to 2.88 μM. Compounds 18-20 and 22-24 increased the level of active caspase 3 by 4-8 folds, compared to the control cells in Panc-1 cell lines compared to doxorubicin as a reference drug. Compounds 18, 22 and 23 were the most caspase-3 inducers. Compounds 22 and 23 increased the levels of caspase-8 and 9 indicating activation of both intrinsic and extrinsic pathways and showed potent induction of Bax, down-regulation of Bcl-2 protein levels and over-expression of cytochrome c levels in Panc-1 human pancreas cancer cells. Compound 23 exhibited mainly cell cycle arrest at the Pre-G1 and G2/M phases in the cell cycle analysis of Panc-1 cell line. The drug likeness profiles of compounds 18-20 and 22-24 were predicted to have good to excellent drug likeness profiles specially compounds 18-20 and 23. Finally molecular docking study was performed at the EGFR active site to suggest thier possible binding mode. The hydroxyimino-phenethyl scaffold compounds 17-24 represent an interesting starting point to optimize their pharmacokinetics and pharmacodynamics profiles.

Novel Water Soluble Chitosan Derivatives with 1,2,3-Triazolium and Their Free Radical-Scavenging Activity

Chitosan is an abundant and renewable polysaccharide, which exhibits attractive bioactivities and natural properties. Improvement such as chemical modification of chitosan is often performed for its potential of providing high bioactivity and good water solubility. A new class of chitosan derivatives possessing 1,2,3-triazolium charged units by associating “click reaction” with efficient 1,2,3-triazole quaternization were designed and synthesized. Their free radical-scavenging activity against three free radicals was tested. The inhibitory property and water solubility of the synthesized chitosan derivatives exhibited a remarkable improvement over chitosan. It is hypothesized that triazole or triazolium groups enable the synthesized chitosan to possess obviously better radical-scavenging activity. Moreover, the scavenging activity against superoxide radical of chitosan derivatives with triazolium (IC₅₀ < 0.01 mg mL⁻¹) was more efficient than that of derivatives with triazole and Vitamin C. In the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical-scavenging assay, the same pattern were observed, which should be related to the triazolium grafted at the periphery of molecular chains.

Design, synthesis, in silico and in vitro antimicrobial screenings of novel 1,2,4-triazoles carrying 1,2,3-triazole scaffold with lipophilic side chain tether

BACKGROUND

1,2,4-Triazoles and 1,2,3-triazoles have gained significant importance in medicinal chemistry.

RESULTS

This study describes a green, efficient and quick solvent free click synthesis of new 1,2,3-triazole-4,5-diesters carrying a lipophilic side chain via 1,3-dipolar cycloaddition of diethylacetylene dicarboxylate with different surfactant azides. Further structural modifications of the resulting 1,2,3-triazole diesters to their corresponding 1,2,4-triazole-3-thiones via multi-step synthesis has been also investigated. The structures of the newly designed triazoles have been elucidated based on their analytical and spectral data. These compounds were evaluated for their antimicrobial activities. Relative to the standard antimicrobial agents, derivatives of 1,2,3-triazole-bis-4-amino-1,2,4-triazole-3-thiones were the most potent antimicrobial agents with compound 7d demonstrating comparable antibacterial and antifungal activities against all tested microorganisms. Further, the selected compounds were studied for docking using the enzyme, Glucosamine-6-phosphate synthase.

CONCLUSIONS

The in silico study reveals that all the synthesized compounds had shown good binding energy toward the target protein ranging from - 10.49 to - 5.72 kJ mol-1 and have good affinity toward the active pocket, thus, they may be considered as good inhibitors of GlcN-6-P synthase.

The latest advances in the discovery of nitric oxide hybrid drug compounds

INTRODUCTION

There is a great interest in Nitric oxide (NO) within medicinal chemistry since it's involved in human signaling pathways. Prodrugs or hybrid compounds containing NO-donor scaffolds linked to an active compound are valuable, due to their potential for modulating many pathological conditions due to NO's biological properties when released in addition to the native drug. Compounds that selectively inhibit nitric oxide synthase isoforms (NOS) can also increase therapeutic capacity, particularly in the treatment of chronic diseases. However, search for bioactive compounds to efficiently and selectively modulate NO is still a challenge in drug discovery. Areas covered: In this review, the authors highlight the recent advances in the strategies used to discover NO-hybrid derivatives, especially those related to anti-inflammatory, cardiovascular, anticancer and anti-microorganism activities. They also focus on: nitric oxide synthase inhibitors, NO delivery materials and other related activities. Expert opinion: The process of molecular hybridization can be used to obtain NO-releasing compounds that also interact with different targets. The main problem with this approach is to control NO multiple actions in the right biological system. However, the use of NO-releasing groups with many different scaffolds leads to new molecular structures for bioactive compounds, suggesting synergies.

Novel 1,2,3-triazolium-functionalized inulin derivatives: synthesis, free radical-scavenging activity, and antifungal activity

A new class of inulin derivatives possessing 1,2,3-triazolium charged units by associating “click reaction” with efficient 1,2,3-triazole quaternization were designed and synthesized. The synthesized inulin derivatives possess excellent free radical-scavenging ability.

Telescoped continuous flow generation of a library of highly substituted 3-thio-1,2,4-triazoles

An integrated continuous flow process for the synthesis of 3-thio-1,2,4-triazoles is reported. A small library of 18 compounds was prepared in just 48 minutes of residence time in moderate to excellent yields.

Nitric oxide-donating derivatives of hederacolchiside A1: Synthesis and biological evaluation in vitro and in vivo as potential anticancer agents

A series of nitric oxide (NO) donating derivatives of hederacolchiside A₁ bearing triterpenoid saponin motif were designed, synthesized and evaluated for their anticancer activity. All of the tested furoxan-based NO releasing compounds showed significant proliferation inhibitory activities. Especially compound 6a exhibited strong cytotoxicity (IC₅₀=1.6-6.5μM) against four human tumor cell lines (SMMC-7721, NCI-H460, U251, HCT-116) in vitro and the highest level of NO releasing. Furthermore, compound 6a was revealed low acute toxicity to mice and weak haemolytic activity with potent tumor growth inhibition against mice H22 hepatocellular cells in vivo (51.5%).

Hybrid molecules: The privileged scaffolds for various pharmaceuticals

The practice of polypharmacology is not a new concept but the approaches which are being adopted for administering the two or more drugs together are varied from time to time. Taking two or more drugs simultaneously, co-formulation of two or more active agents in a single tablet and development of hybrid molecular entities capable to modulate multiple targets are the three popular approaches for multidrug therapy. The simultaneous use of more than one drug for the chemotherapy of a single disease demands a lot of patient compliance. Hence the present form of polypharmacology is gaining popularity in the form of hybrid molecules (multiple ligand approach). From the last 1-2 decades, the synthesis of hybrid molecules by the combination of different biologically relevant moieties has been under constant escalation along with their evaluation as diverse range of pharmacological agents and as potent drugs. This review is focused on the biological potential of hybrid molecules with particular mention of those exhibiting anti-fungal, anti-tuberculosis, anti-malarial, anti-inflammatory and anti-cancer activities. A comparison of the drug potency of the hybrid molecules with their individual counterparts is discussed for quantifying the significance of the concept of molecular hybridisation.

Synthesis and Antiproliferative Activities of Benzimidazole-Based Sulfide and Sulfoxide Derivatives

The design, synthesis, and in vitro antiproliferative activity of a novel series of sulfide (4a-i) and sulfoxide (5a-h) derivatives of benzimidazole, in which different aromatic and heteroaromatic acetamides are linked to benzimidazole via sulfide (4a-i) and sulfoxide (5a-h) linker, are reported and the structure-activity relationship is discussed. The new derivatives were prepared by coupling 2-(mercaptomethyl)benzimidazole with 2-bromo-N-(substituted) acetamides in dry acetone in the presence of anhydrous potassium carbonate. With very few exceptions, all of the synthesized compounds showed varying antiprolific activities against HepG2, MCF-7, and A549 cell lines. Compound 5a was very similar in potency to doxorubicin as an anticancer drug, with IC50 values 4.1 ± 0.5, 4.1 ± 0.5, and 5.0 ± 0.6 µg/mL versus 4.2 ± 0.5, 4.9 ± 0.6, and 6.1 ± 0.6 µg/mL against HepG2, MCF-7, and A549 cell lines, respectively. In contrast, none of the compounds showed activity against human prostate PC3 cancer cells. Additionally, the sulfoxide derivatives were more potent than the corresponding sulfides.

Propyphenazone-based analogues as prodrugs and selective cyclooxygenase-2 inhibitors

Improving the gastrointestinal safety profile of nonsteroidal anti-inflammatory drugs (NSAIDs) is an important goal. Herein, we report two strategies, using the nonacidic propyphenazone structure, with potential to overcome the side effects of NSAIDs. Propyphenazone was employed to temporarily mask the free acid group of the widely used NSAIDs ibuprofen, diclofenac, and ketoprofen to develop three mutual prodrugs hypothesized to have minimal GI irritation. The three prodrugs exhibit in vivo anti-inflammatory and analgesic activities with improved potency over each parent drug when compared to a nonhydrolyzable control betahistine-propyphenazone (BET-MP). Additionally, ANT-MP formed by the irreversible coupling of propyphenazone and 4-aminoantipyrine, displayed exceptional COXII selectivity (COXII IC50 of 0.97 ± 0.04 μM, compared to no observed inhibition of COXI at 160 μM). Inhibition of COXII suppresses inflammatory diseases without affecting COXI-mediated GI tract events. ANT-MP exhibited maximal analgesic effect when tested in vivo in an abdominal writhing assay (100% protection) and its anti-inflammatory activity showed a peak at 2 h in a carrageenan-induced paw edema model. Its unique selectivity toward the COXII enzyme was investigated using molecular modeling techniques.