Heteroatom Chemistry最新文献

The promising approach toward the synthesis of novel sulfur-based quinoline and benzoquinoline isostere molecules. The condensation reaction involves 4-chloro-2,8-dimethylquinolines or 4-chloro-2-methylbenzo[h]quinoline and corresponding o-thiosalicylic acid and 2-mercaptonicotinic acid, either in ethanol (as a solvent) or under solvent-free (neat) conditions. This results in the formation of an intermediate, which yields significantly better results when using neat solvent-free conditions. The intermediates then undergo cyclization using polyphosphoric acid (PPA). Notably, the sulfur-based quinoline and benzoquinoline isosteres are prepared through a highly efficient one-pot methodology using CuI/Cs₂CO₃/DMSO conditions, which yields higher than the PPA condition through a step-by-step method. The synthesized novel sulfur-containing isosteres are further analyzed through quantum chemical calculations of the frontier molecular orbitals (FMOs) and molecular electrostatic potential (MEP) using the M06-2X method with a 6-311 + G (d, p) basis set in water. Additionally, in silico analyses are performed in detail to predict the potential biological activity of the synthesized molecules through molecular docking and MM-GBSA analysis against the CDK8/CycC complex. Furthermore, ADME parameters have been analyzed, and all the final cyclized molecules show the most promising drug-like properties, inspiring further research in medicinal chemistry.

A series of 2,3-dihydro-1,5-benzodiazepine derivatives have been synthesized and characterized using IR, NMR, GC-MS, single crystal XRD, and microanalysis. The results of their antibacterial activity against methicillin-resistance Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Bacillus subtilis, Streptococcus mutans, Pseudomonas aeruginosa, Salmonella typhi, and Streptococcus pyrogens indicated that most of the compounds were bacteriostatic (0.125−4 mg/mL) and also exhibited good biofilm inhibition (0.21−72.69%). The compounds were found to be synergistic when used in combination with other antibiotics. The antiproliferative and cytotoxic effects were also investigated against PC-3 prostate cancer and RAW 264.7 macrophage cell lines, respectively, using the MTT assay. Apart from compounds 6 and 7, a good number of the compounds (1, 2, 3, 4, 5, and 8) were selectively toxic to the prostate cancer cells at 20 µM, whilst sparing the normal cells. Compound 3 demonstrated the highest antiprostate cancer effect by reducing the viability of PC-3 cells to (13.75%), which was followed by compounds 1 (47.72%), 2 (48.18%), 4 (62.61%), 5 (66.70%), and 8 (69.55%).

Eleven conjugates between dihydroartemisinin (DHA) with thiols containing both ether and thioether bonds were designed, synthesized by a two-step procedure including etherification and S-alkylation. Analysis of the NMR spectral data indicated that the dimer of DHA with thiols 6-mercaptopurine and 2-mercaptoimidazole was produced with yields of 31% and 62%, respectively. Furthermore, the tautomerization of thiol 5-methoxy-2-mercaptobenzimidazole led to the formation of a mixture of two isomers in which they might be interchangeable through a dynamic tautomeric equilibrium in the solution. Screening in vitro biological activities revealed that most of the synthesized conjugates showed good cytotoxic and anti-inflammatory activity, while three of them displayed α-glucosidase inhibitory activity. Notably, two conjugates 5d and 5e of DHA with thiols 2-mercaptopyrimidine and 2-mercaptobenzothiazole had an effect in all tested activities in which conjugate 5e is the most potent.

An unsymmetrical salen-type Schiff base ligand, (Z)-1-(((2-((E)-(2-hydroxy-6-methoxybenzylidene)amino)phenyl)amino)methylene)naphthalen-2(1H)-one, and its Zn(II), Cu(II), Co(II), Mn(II), and Fe(III) complexes were synthesized and characterized by mass (MS), nuclear magnetic resonance (NMR), infrared (IR), ultraviolet-visible (UV-Vis) spectra, and effective magnetic moments. The thermal analyses of the obtained ligand and metal complexes were conducted by thermogravimetric analysis (TGA). Antimicrobial activity of the unsymmetrical Schiff base ligand and its metal complexes were examined for Staphylococcus aureus as Gram-positive bacteria and Escherichia coli as Gram-negative bacteria. In vitro anticancer property of synthetic compounds was estimated against human cancer cell lines, a subline of Hela tumor cell line (KB), and a human liver cancer cell line (HepG-2) as well.

A library of six compounds with new hybrids in a single molecule triazole ring attached to the phosphonium salts was synthesized. Click chemistry was, however, used to synthesize the 1-, 2-, and 3-triazole intermediates as a tether for the hybrid phosphonium salts. Their antibacterial activity against Gram-positive bacteria (Staphylococcus aureus and Enterococcus faecalis), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa), and Mycobacterium smegmatis mc²155 was determined using the HT-SPOTi assay. Compound 2 showed the most effective antimicrobial activity as it inhibited the growth of Pseudomonas aeruginosa and Staphylococcus aureus at 0.0125 µg/mL and 31.25 µg/mL, respectively. From the FICI data, compounds 2ET-TOL (2) and RABYL-TOL (4) successfully modulated the activities of amoxicillin against Pseudomonas aeruginosa and Staphylococcus aureus. All the test compounds exhibited a concentration-dependent biofilm formation inhibition against S. aureus, except P-Z (compound 6). Compounds P-MEOXY (1) and 2ET-TOL (2) exhibited mild activity against P. aeruginosa with compound 4 showing antimycobacterial activity at 500 µg/mL.

Fifteen new pyrazole-4-carboxylic oxime ester derivatives were conveniently synthesized, and their structures were confirmed by ¹H NMR, ¹³C NMR, HRMS, and X-ray diffraction. Antifungal assays indicated that some of these compounds possessed good activity against S. sclerotiorum, B. cinerea, R. solani, P. oryae, and P. piricola at 50 ppm. Structure-activity relationships (SAR) were studied by molecular docking simulation.

Two isopropyl (3-methyl-1-oxo-1-((1-((4-(prop-2-yn-1-yloxy)phenyl)thio)propan-2-yl)amino)butan-2-yl)carbamate diastereomers were isolated. Fungicidal activities indicated that the isolated four chiral compounds possessed excellent activity against P. capsici with the EC₅₀ value of 4a (1.30 μg/mL), 4b (0.078 μg/mL), 4c (1.85 μg/mL), and 4d (44.4 μg/mL). Among them, compound 4b exhibited remarkably high activities against Phytophthora capsici, which is better than that of positive control dimethomorph. Its R and S isomers showed that chiral influences the activity against P. capsici.