Design, synthesis and biological assessment of new selective COX-2 inhibitors including methyl sulfonyl moiety.

Nonsteroidal anti-inflammatory drugs (NSAIDs) cause peptic lesions in the gastrointestinal mucosa by inhibiting the cyclooxygenase-1 (COX-1) enzyme. Selective COX-2 inhibition causes decreased side effects over current NSAIDs. Therefore, the studies about selective inhibition of COX-2 enzyme are very important for new drug development. The design, synthesis and biological activity evaluation of novel derivatives bearing thiazolylhydrazine-methyl sulfonyl moiety as selective COX-2 inhibitors were aimed in this paper. The structures of synthesized compounds were assigned using different spectroscopic techniques such as 1H NMR, 13C NMR and HRMS. In addition, the estimation of ADME parameters for all compounds was carried out using in silico process. The evaluation of in vitro COX-1/COX-2 enzyme inhibition was applied according to the fluorometric method. According to the enzyme inhibition results, synthesized compounds showed the selectivity against COX-2 enzyme inhibition as expected. Compounds 3a, 3e, 3f, 3g, 3i and 3j demonstrated significant COX-2 inhibition potencies. Among them, compound 3a was found to be the most effective derivative with an IC50 value of 0.140 ± 0.006 µM. Moreover, it was seen that compound 3a displayed a more potent inhibition profile at least 12-fold than nimesulide (IC50 = 1.684 ± 0.079 µM), while it showed inhibitory activity at a similar rate of celecoxib (IC50 = 0.132 ± 0.005 µM). Molecular modelling studies aided in the understanding of the interaction modes between this compound and COX-2 enzyme. It was found that compound 3a had a significant binding property. In addition, the selectivity of obtained derivatives on COX-2 enzyme could be explained and discussed by molecular docking studies.

Synthesis, characterization and carbonic anhydrase I and II inhibitory evaluation of new sulfonamide derivatives bearing dithiocarbamate.

In this study, novel dithiocarbamate-sulfonamide derivatives (3a-3k) were synthesized to investigate their inhibitory activity on purified human carbonic anhydrase (hCA) I and II. The IC50 and Ki values of the compounds were calculated to compare their inhibition profiles on hCA I and II isoenzymes. Acetazolamide was used as the standard inhibitor in the enzyme inhibition assay. Compounds 3a, 3e, 3g, 3h, 3j and 3k showed notable inhibitory effects against hCA I and II. Among these compounds, compound 3h was found to be the most active derivate against both the hCA I and II enzymes with Ki values of 0.032 ± 0.001 µM and 0.013 ± 0.0005 µM, respectively. The cytotoxicity of compounds 3a, 3e, 3g, 3h, 3j and 3k toward NIH/3T3 (mouse embryonic fibroblast cell line) was observed and the compounds were found to be non-cytotoxic. Furthermore, molecular docking studies were performed to investigate the interaction types between compound 3h and the hCA I and II enzymes. As a result of this study a novel and potent class of CA inhibitors with good activity potential were identified.

Synthesis and biological evaluation of novel 1,3,4-thiadiazole derivatives as possible anticancer agents.

The synthesis of new N-(5-substituted-1,3,4-thiadiazol-2-yl)-2-[(5-(substituted amino)-1,3,4-thiadiazol-2-yl)thio]acetamide derivatives and investigation of their anticancer activities were the aims of this work. All the new compounds' structures were elucidated by elemental analyses, IR, 1H NMR, 13C NMR and MS spectral data. Anticancer activity studies of the compounds were evaluated against MCF-7 and A549 tumor cell lines. In addition, with the purpose of determining the selectivity of cytotoxic activities, the most active compound was screened against a noncancer NIH3T3 cell line (mouse embryonic fibroblast cells). Among the tested compounds, compound 4y (N-(5-ethyl-1,3,4-thiadiazol-2-yl)-2-((5-(p-tolylamino)-1,3,4-thiadiazol-2-yl)thio)acetamide), showed promising cytotoxic activity against MCF7 cancer cell with an IC 50value of 0.084 ± 0.020 mmol L-1 and against A549 cancer cell with IC 50 value of 0.034 ± 0.008 mmol L-1, compared with cisplatin. The aromatase inhibitory activity was evaluated for compound 4y on MCF-7 cell line showing promising activity with IC50 of 0.062 ± 0.004 mmol L-1.

Synthesis, molecular docking analysis and carbonic anhydrase I-II inhibitory evaluation of new sulfonamide derivatives.

New sulfonamide-hydrazone derivatives (3a-3n) were synthesized to evaluate their inhibitory effects on purified human carbonic anhydrase (hCA) I and II. The inhibition profiles of the synthesized compounds on hCA I-II isoenzyme were investigated by comparing their IC50 and Ki values. Acetazolamide (5-acetamido-1,3,4-thiadiazole-2-sulfonamide, AZA) has also been used as a standard inhibitor. The compound 3e demonstrated the best hCA I inhibitory effect with a Ki value of 0.1676 ±â€¯0.017 µM. Besides, the compound 3m showed the best hCA II inhibitory effect with a Ki value of 0.2880 ±â€¯0.080 µM. Cytotoxicity of the compounds 3e and 3m toward NIH/3T3 mouse embryonic fibroblast cell line was observed and the compounds were found to be non-cytotoxic. Molecular docking studies were performed to investigate the interaction types between active compounds and hCA enzymes. Pharmacokinetic profiles of compounds were assessed by theoretical ADME predictions. As a result of this study a novel and potent class of CA inhibitors were identified with a good activity potential.

Synthesis and Evaluation of Heterocycles Based Chalcone Derivatives as Antiproliferative Agents.

BACKGROUND: The lack of selectivity and development of drug-resistance encourage researchers to search for novel, more efficient and multi-targeted agents with less toxicity. OBJECTIVE: In this paper, a series of novel chalcone derivatives bearing diverse heterocycles have been synthesized and evaluated for their antiproliferative activity against A549 (Human Lung Adenocarcinoma) and C6 (Rat Brain Glioma) cells. METHOD: Structures of the title compounds (3-18) were verified by FT-IR, 1H NMR, 13C NMR, HRMS spectral data and elemental analyses. Antiproliferative activities of the compounds were evaluated using MTT assay, BrdU method, and flow cytometric analysis. RESULTS: Compounds 9 and 15 were revealed as the most promising cytotoxic agents due to their selectivity towards A549 cells with lower IC50 values (IC50=0.05 µM and IC50=0.0316 µM) than cisplatin (IC50=0.06 µM). Flow cytometric analysis of compounds 9 and 15 showed that they affected lung cancer cells by the apoptotic pathway. CONCLUSION: It is concluded that this study will contribute to the research of novel antiproliferative agents.

The synthesis, antifungal and apoptotic effects of triazole-oxadiazoles against Candida species.

In search of potent and safe antifungal agents, herein, we report the synthesis, characterization and biological activities of triazole-oxadiazole compounds. The structural verification of the molecules was carried out by 1H NMR, 13C NMR and mass spectral data. The in vitro antifungal and apoptotic activity were investigated against C. albicans, C. parapsilosis, C. krusei and C. glabrata. The compounds namely N-(4-nitrophenyl)-2-[(5-(2-((4-methyl-4H-1,2,4-triazol-3-yl)thio)ethyl)-1,3,4-oxadiazol-2-yl)thio]acetamide (4e) and N-(6-fluorobenzothiazol-2-yl)-2-[(5-(2-((4-methyl-4H-1,2,4-triazol-3-yl)thio)ethyl)-1,3,4-oxadiazol-2-yl)thio]acetamide (4i) were detected as the most potent compounds against C. albicans and C. glabrata (MIC90 = 62.5 µg/mL). According to studies on their mechanism of action, it was confirmed that compound 4i has apoptotic effect on four Candida via Annexin V-PI with flow cytometry. The MTT assay revealed that all compounds were determined to be non-toxic against healthy cells in the tested concentrations.

Synthesis and Biological Evaluation of New Thiosemicarbazone Derivative Schiff Bases as Monoamine Oxidase Inhibitory Agents.

Twenty-six novel thiosemicarbazone derivative B1-B26 were synthesized via condensation reactions between the corresponding thiosemicarbazides and aldehydes. The chemical characterization of the compounds was carried out by infrared (IR), mass (MS), proton and carbon nuclear magnetic resonance (¹H- and 13C-NMR) spectroscopic analyses. The compounds were investigated for their monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B) inhibitory activity and most of them were more potent against MAO-A enzyme when compared with MAO-B enzyme. N-Cyclohexyl-2-[4-[(4-chlorophenyl)thio]benzylidene]hydrazine-1-carbothioamide (B24) was the most active compound against MAO-A. The enzyme kinetics study revealed that compound B24 has a reversible and competitive mode of binding. Interaction modes between compound B24 and MAO-A were clarified by docking studies. In addition, the favourable absorption, distribution, metabolism, and excretion (ADME) properties and non-toxic nature of compound B24 make this compound a promising MAO-A inhibitor.

Design and Synthesis of New Benzothiazole Compounds as Selective hMAO-B Inhibitors.

In the current work a new class of novel benzothiazole-hydrazone derivatives was designed and synthesized as hMAO-B inhibitors. Structures of the obtained compounds (3a-3j) were characterized by IR, ¹H-NMR, 13C-NMR, and HRMS spectroscopic methods. The inhibitory activity of compounds (3a-3j) against hMAO-A and hMAO-B enzymes was evaluated by using an in vitro fluorometric method. According to activity results, some of the synthesized compounds displayed selective and significant hMAO-B enzyme inhibitor activity. Compound 3e was the most active derivative in the series with an IC50 value of 0.060 µM. Furthermore, cytotoxicity of compound 3e was investigated and found to be non-cytotoxic. Absorption, distribution, metabolism, and excretion (ADME) and blood-brain barrier (BBB) permeability predictions were performed for all compounds. It was determined that these compounds may have a good pharmacokinetic profiles. Binding modes between the most active compound 3e and the hMAO-B enzyme were analyzed by docking studies. It was observed that there is a strong interaction between compound 3e and enzyme active site.

Synthesis and Anticandidal Activity Evaluation of New Benzimidazole-Thiazole Derivatives.

Azole-based antifungal agents constitute one of the important classes of antifungal drugs. Hence, in the present work, 12 new benzimidazole-thiazole derivatives 3a-3l were synthesized to evaluate their anticandidal activity against C.albicans, C.glabrata, C.krusei, and C.parapsilopsis. The structures of the newly synthesized compounds 3a-3l were confirmed by IR, ¹H-NMR, 13C-NMR, and ESI-MS spectroscopic methods. ADME parameters of synthesized compounds 3a-3l were predicted by an in-slico study and it was determined that all synthesized compounds may have a good pharmacokinetic profile. In the anticandidal activity studies, compounds 3c and 3d were found to be the most active compounds against all Candida species. In addition, cytoxicity studies showed that these compounds are nontoxic with a IC50 value higher than 500 µg/mL. The effect of compounds 3c and 3d on the ergosterol level of C.albicans was determined by an LC-MS-MS method. It was observed that both compounds cause a decrease in the ergosterol level. A molecular docking study including binding modes of 3c to lanosterol 14α-demethylase (CYP51), a key enzyme in ergosterol biosynthesis, was performed to elucidate the mechanism of the antifungal action. The docking studies revealed that there is a strong interaction between CYP51 and the most active compound 3c.