Molecular docking studies, biological evaluation and synthesis of novel 3-mercapto-1,2,4-triazole derivatives

An Industrial Approach to Production of Tofacitinib Citrate (TFC) as an Anti-COVID-19 Agent: A Joint Experimental and Theoretical Study

In this report, we have presented our experience about a facile method for synthesis of tofacitinib citrate (TFC). The developed analytical methods for identification and qualifications are also included. As TFC seems to be effective in treatment of the symptoms of COVID-19 (SARS family), manufacturing of this active pharmaceutical ingredient (API) could be helpful. The API of TFC was prepared from the diamine intermediate in an ambient and solvent-free condition. Elimination of the reaction solvent resulted in decreasing the cost and preventing the rejection of the organic volatile impurity (OVI) test. The final citrate addition step was carried out using water as a solvent (the citrate content was 37.5% by potentiometry). Moreover, the results of the Karl-Fischer (KF) titration analysis was about 0.24%, which showed that the use of water does not increase the water content of the crystal structure.

Targeting new N-furfurylated 4-chlorophenyl-1,2,4-triazolepropionamide hybrids as potential 15-lipoxygenase inhibitors supported with in vitro and in silico studies

Lipoxygenases (LOXs) are a group of enzymes that catalyze the oxidation of polyunsaturated fatty acids and initiate the biosynthesis of secondary metabolites that are involved to control inflammation. In search of new and more potent LOX inhibitors, a series of new 3-(5-(4-chlorophenyl)-4-(2-furylmethyl)-1,2,4-triazole hybrids was prepared and screened for its LOX inhibitory potential. 4-Chlorobenzoic acid (a) was metamorphosed into N-furfuryl-5-(4-chlorophenyl)-4-(2-furylmethyl)-1,2,4-triazole (4) via intermediates like benzoate (1), hydrazide (2) and semicarbazide (3). Finally, triazole (4) was fused with propionamides (6a-o) and transformed it into the aimed derivatives (7a-o). The structural interpretations of the prepared derivatives (7a-o) were accomplished via FTIR, ¹H-, ¹³C-NMR spectroscopy, EI-MS and HR-EI-MS spectrometry. The inhibitory potency of the compounds against soybean 15-LOX was determined by in vitro assay using chemiluminescence method. Compounds 7a and 7f exhibited potent LOX inhibitory profiles with IC₅₀ 21.83 ± 0.56 and 25.72 ± 0.51 µM, whereas 7d and 7e showed comparable inhibitory potential with IC₅₀ values of 34.52 ± 0.39 and 39.12 ± 0.46 µM, respectively. Compounds 7a, 7f, 7d and 7e exhibited 65.58 ± 1.4%, 54.72 ± 1.3%, 58.52 ± 1.2% and 63.56 ± 1.4% blood mononuclear cells viability, respectively. Density functional theory and molecular docking studies further strengthened the studies of the synthesized compounds and these derivatives perceived to be potential 'lead' compounds in drug discovery as anti-LOX.Communicated by Ramaswamy H. Sarma.

Facile synthesis, spectroscopic evaluation and antimicrobial screening of metal endowed triazole compounds

The scientific interest in developing new complexes as inhibitors of bacterial biofilm related infections is constantly rising. The present work describes the chemical synthesis, structural and biological scrutiny of a triazole Schiff base ligand and its corresponding complexes. Triazole Schiff base, (2-methoxy-4-[(1H-1,2,4-triazol-3-ylimino)methyl]phenol) was synthesized from the condensation reaction of 3-amino-1,2,4-triazole and 4-hydroxy-3-methoxybenzaldehyde in an equimolar ratio. The triazole ligand (H₂L) was characterized by physical (solubility, color, melting point), spectroscopic [UV-visible (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (¹H-NMR) and mass spectra (MS)] and micro analysis to evaluate their elemental composition. The bidentate ligand was complexed with transition metal [VO(IV), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II)] in 1:2 molar ratio. The complexes were characterized by physical (color, solubility, decomposition temperature, conductance and magnetic moment), FT-IR, UV-Vis and elemental analysis. Thermal stability and fluorescence properties of the compounds were also determined. Density functional theory based theoretical calculations were accomplished to gain more insight into spectroscopic properties. The frontier molecular orbital analysis revealed that the ligand was less reactive with reduced electron donating capability and more kinetic stability than complexes. The as-synthesized compounds were scrutinized for anti-bacterial and anti-fungal activity against selected strains. Cobalt complex exhibited highest antibacterial activity against Escherichia coli and nickel complex has shown highest antifungal activity against Aspergillus niger. All the compounds also showed good antioxidant activity. The theoretical results reflect consistency with the experimental findings signifying that such compounds could be the promising chemical scaffolds in the near future against microbial infectious.

(±)-2-{[4-(4-Bromophenyl)-5-phenyl-4H-1,2,4-triazol-3-yl]sulfanyl}-1-phenyl-1-ethanol

The novel racemic secondary alcohol (±)-2-{[4-(4-bromophenyl)-5-phenyl-4H-1,2,4-triazol-3-yl]sulfanyl}-1-phenyl-1-ethanol (12) has been successfully synthesized through S-alkylation of 4-(4-bromophenyl)-5-phenyl-4H-1,2,4-triazole-3-thiol (10) in alkaline medium with 2-bromo-1-phenylethanone followed by reduction of the corresponding ketone 11. All the synthesized compounds were characterized by IR, 1D (1H, 13C, DEPT135) and 2D (1H-1H, 1H-13C and 1H-15N) NMR spectroscopy, elemental analysis and HRMS spectrometry.

(R,S)-2-{[4-(4-Methoxyphenyl)-5-phenyl-4H-1,2,4-triazol-3-yl] thio}-1-phenyl-1-ethanol

4-(4-Methoxyphenyl)-5-phenyl--4H-1,2,4-triazole-3-thiol (4) was alkylated to 2-{[4-(-4-methoxyphenyl)-5-phenyl-4H-1,2,4-triazol-3-yl]thio}-1-phenylethan-1-one (5) in alkaline conditions using 2-bromo-1-phenylethanone. The alkylated compound (5) was reduced at the carbonyl group to the corresponding racemic secondary alcohol with an asymmetric carbon, (R,S)-2-{[4-(4-methoxyphenyl)-5-phenyl-4H-1,2,4-triazol-3-yl]thio}-1-phenyl-1-ethanol (6). Both synthesized compounds, ketone (5) and secondary alcohol (6), are new and have not been reported yet in the literature. All the synthesized compounds were characterized by IR, 1D and 2D NMR 1H-1H, 1H-13C and 1H-15N-NMR spectroscopy and by elemental analysis.

A review: Pharmacological aspects of metal based 1,2,4-triazole derived Schiff bases

Clinical reports have highlighted the radical increase of antibiotic resistance. As a result, multidrug resistance has emerged as a serious threat to human health. Many organic compounds commonly used as drugs in the past, no longer have pure organic mode of action rather need bio-transformation or more activation. Bulk of research has shown that they need trace amount of metal ions incorporated within the chemistry of bioactive molecules for enhancement of their potentiality to fight aggressively against resistance. The deficiency of some metal ions can also be responsible for many diseases like growth retardation, pernicious anemia and heart diseases in infants. To overcome these problems, there is a need to introduce novel strategies which have new mechanism of action along with significant spectrum of biological activity, enhanced safety and efficacy. Bioinorganic compounds have played imperative role in developing the new strategy in the form of "Metal Based Drugs". In current years there have been momentous rise of interest in the application of metal based Schiff base compounds to treat various diseases which are difficult to be treated with conventional methodologies. The unique properties of metal chelates acting as an intermediate between conventional organic and inorganic compounds provided innovative opportunities in the field of pharmaceutical chemistry. In this review, we have exclusively focused on the search of metal based 1,2,4-triazole derived Schiff base compounds (synthesized, reported and reviewed in the past ten years) that possess various biological activities such as antifungal, antibacterial, antioxidant, antidiabetic, anthelmintic, anticancer, antiproliferative, cytotoxic and DNA-intercalation activity.

Unravelling the anticancer potency of 1,2,4-triazole-N-arylamide hybrids through inhibition of STAT3: synthesis and in silico mechanistic studies

The discovery of potent STAT3 inhibitors has gained noteworthy impetus in the last decade. In line with this trend, considering the proven biological importance of 1,2,4-triazoles, herein, we are reporting the design, synthesis, pharmacokinetic profiles, and in vitro anticancer activity of novel C3-linked 1,2,4-triazole-N-arylamide hybrids and their in silico proposed mechanism of action via inhibition of STAT3. The 1,2,4-triazole scaffold was selected as a privilege ring system that is embedded in core structures of a variety of anticancer drugs which are either in clinical use or still under clinical trials. The designed 1,2,4-triazole derivatives were synthesized by linking the triazole-thione moiety through amide hydrophilic linkers with diverse lipophilic fragments. In silico study to predict cytotoxicity of the new hybrids against different kinds of human cancer cell lines as well as the non-tumor cells was conducted. The multidrug-resistant human breast adenocarcinoma cells (MDA-MB-231) was found most susceptible to the cytotoxic effect of synthesized compounds and hence were selected to evaluate the in vitro anticancer activity. Four of the designed derivatives showed promising cytotoxicity effects against selected cancer cells, among which compound 12 showed the highest potency (IC₅₀ = 3.61 µM), followed by 21 which displayed IC₅₀ value of 3.93 µM. Also, compounds 14 and 23 revealed equipotent activity with the reference cytotoxic agent doxorubicin. To reinforce these observations, the obtained data of in vitro cytotoxicity have been validated in terms of ligand-protein interaction and new compounds were analyzed for ADMET properties to evaluate their potential to build up as good drug candidates. This study led us to identify two novel C3-linked 1,2,4-triazole-N-arylamide hybrids of interesting antiproliferative potentials as probable lead inhibitors of STAT3 with promising pharmacokinetic profiles.