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This work focused on analyzing the properties of N-(5-nitrothiazol-2-yl)furan-2-carboxamide (C 8 H 5 N 3 O 4 S, NTFC) as a possible inhibitor of the rheumatoid arthritis process. The synthesis of NTFC was carried out and good-quality crystals were obtained and studied by NMR ( 1 H and 13 C), DEPT 135, UV-Vis, IR, MS and single-crystal X-ray diffraction. The structure of NTFC consists of two rings, thiazole and furan, and a central C-N-C(=O)-C segment, which appears to be planar. This central amide segment forms angles of 2.61 (10) and 7.97 (11)° with the planes of the thiazole and furan rings, respectively. The crystal structure of NTFC exhibits N-H...N, N-H...O and C-H...O hydrogen bonds, and C-H...π and π-π interactions that facilitate self-assembly and the formation of hydrogen-bonded dimers, which implies the appearance of R 2 2 (8) graph-set motifs in this interaction. The stability of the dimeric unit is complemented by the formation of strong intramolecular C-S...O interactions of chalcogen character, with an S...O distance of 2.6040 (18) Å. Hirshfeld surface (HS) analysis revealed that O...H/H...O interactions were dominant, accounting for 36.8% of the total HS, and that N-H...N interactions were fundamental to the formation of the dimeric structure. The molecular electrostatic potential (MEP) map showed a maximum energy of 46.73 kcal mol -1 and a minimum of -36.06 kcal mol -1 . The interaction energies of molecular pairs around NTFC are highest for those interactions linked by N-H hydrogen bonds. The properties of the NTFC ligand as a potential inhibitor of the DHODH (dihydroorotate dehydrogenase) enzyme were evaluated by molecular docking, showing coupling energies very close to those obtained with the control drug for rheumatoid arthritis, i.e. leflunomide.

The γ-lactam ring is a prominent feature in medicinal chemistry, and its synthesis has garnered significant interest due to its valuable properties. Among the γ-lactams, 2-oxopyrrolidine-3-carbonitrile derivatives stand out as versatile synthons that can be readily transformed into a variety of other functional groups. In this work, we successfully synthesized highly functionalized 3-cyano-2-pyrrolidinones with moderate to good overall yields using the Ugi reaction followed by intramolecular Michael addition. The process demonstrated excellent diastereoselectivity and showed good tolerance to a range of isonitriles and carbonyl compounds., (© 2024 Wiley-VCH GmbH.)

Paeonol is a broadly studied natural product due to its many biological activities. Using a methodology previously employed by our research group, 11 derivatives of paeonol were synthesized (seven of them are unpublished compounds), including four ethers and seven benzofurans. Additionally, we determined the crystal structure of one of these ether derivatives (1 a) and of five benzofuran derivatives (2 a, 2 b, 2 c, 2 f and 2 g) by single crystal X-ray diffraction. To continue studying the cytotoxicity of this natural product and its derivatives, all compounds were tested against two cancer cell lines, HCT116 and MCF-7. Compounds 2 b, 2 e, and 2 g were considered active against the colorectal adenocarcinoma cells HCT116 (Growth inhibition >60 %). Compound 2 e showed an IC 50 of 0.2 μM and was selected for further analysis, results reinforce its anticancer potential., (© 2024 Wiley-VHCA AG, Zurich, Switzerland.)

The synthesis and structural characterization of three families of coordination complexes synthesized from 4'-phenyl-2,2':6',2''-terpyridine (8, Ph-TPY), 4'-(4-chlorophenyl)-2,2':6',2''-terpyridine (9, ClPh-TPY) and 4'-(4-methoxyphenyl)-2,2':6',2''-terpyridine (10, MeOPh-TPY) ligands with the divalent metals Co 2+ , Fe 2+ , Mn 2+ and Ni 2+ are reported. The compounds were synthesized from a 1:2 mixture of the metal and ligand, resulting in a series of complexes with the general formula [M(R-TPY) 2 ](ClO 4 ) 2 (where M = Co 2+ , Fe 2+ , Mn 2+ and Ni 2+ , and R-TPY = Ph-TPY, ClPh-TPY and MeOPh-TPY). The general formula and structural and supramolecular features were determinated by single-crystal X-ray diffraction for bis(4'-phenyl-2,2':6',2''-terpyridine)nickel(II) bis(perchlorate), [Ni(C 21 H 15 N 3 ) 2 ](ClO 4 ) 2 or [Ni(Ph-TPY) 2 ](ClO 4 ) 2 , bis[4'-(4-methoxyphenyl)-2,2':6',2''-terpyridine]manganese(II) bis(perchlorate), [Mn(C 22 H 17 N 3 O) 2 ](ClO 4 ) 2 or [Mn(MeOPh-TPY) 2 ](ClO 4 ) 2 , and bis(4'-phenyl-2,2':6',2''-terpyridine)manganese(II) bis(perchlorate), [Mn(C 21 H 15 N 3 ) 2 ](ClO 4 ) 2 or [Mn(Ph-TPY) 2 ](ClO 4 ) 2 . In all three cases, the complexes present distorted octahedral coordination polyhedra and the crystal packing is determined mainly by weak C-H...π interactions. All the compounds (except for the Ni derivatives, for which FT-IR, UV-Vis and thermal analysis are reported) were fully characterized by spectroscopic (FT-IR, UV-Vis and NMR spectroscopy) and thermal (TGA-DSC, thermogravimetric analysis-differential scanning calorimetry) methods.

The untapped potential of α-carbonyl sulfoxonium ylides in epoxide ring-opening reactions has been a notable gap in current research, with such reactivity predominantly associated with the highly reactive dimethylsulfoxonium methylide. This study introduces an innovative approach wherein an epoxide indole, formed in situ from 2-hydroxyindoline-3-triethylammonium bromide, undergoes reaction with α-ester sulfoxonium ylides. The outcome is the efficient synthesis of a range of 2-hydroxyindolin-3-ylidenes, demonstrating favorable yields (41-81%) and Z / E ratios from 4:1 to those of exclusive Z isomers. Additionally, the photophysical properties of the synthesized indolinylidenes are explored, along with their derivatization using various nucleophiles under acid catalysis.

This work presents an innovative approach to obtain a multifunctional hybrid material operating via combined anti-Stokes (upconversion) and Stokes (downshifting) emissions for oxygen gas sensing and related functionalities. The material is based on a Cu(I) complex exhibiting thermally activated delayed fluorescence emission (TADF) and infrared-to-visible upconverting Tm 3+ /Yb 3+ -doped NaYF 4 nanoparticles supported in a polystyrene (PS) matrix. Excitation of the hybrid material at 980 nm leads to efficient transfer of Tm 3+ emission in the ultraviolet/blue region to the Cu(I) complex and consequently intense green emission (560 nm) of the latter. Additionally, the green emission of the complex can also be directly generated with excitation at 360 nm. Independently of the excitation wavelength, the emission intensity is efficiently suppressed by the presence of molecular oxygen and the quenching rate is properly characterized by the Stern-Volmer plots. The results indicate that the biocompatible hybrid material can be applied as an efficient O 2 sensor operating via near-infrared or ultraviolet excitation, unlike most optical oxygen sensors currently available which only work in downshifting mode.

The current work reports a joint experimental and theoretical study of a novel Cu(II) complex [CuL(μ-CH 3 COO)] 2 , based on 2-acetylpyridine-benzoylhydrazone ligand (HL). The two Cu(II) atoms are five-coordinated, consisting of three NNO-donor atoms from the hidrazone ligand connected by acetate bridges. In addition to the structural analysis, the complete characterization includes magnetic susceptibility, elemental analysis, FT-IR and UV-Vis. Two different approaches of Density Functional Theory (DFT) with localized basis set and plane waves were performed. The theoretical calculations were used to optimize the complex geometry of the new structure allowing a better understanding of its spectroscopic properties with insights of most important interactions. Thereunto, we made a comparison between the following functionals: B3LYP, PBE1PBE, B3PW91, ω-B97XD, M06 (hybrids), CAM-B3LYP (long range hybrid), and B97-d (pure), using localized basis set, and for plane waves we used the PW91 functional. Considering the expected antifungal and antibacterial activity of hydrazone derivative ligand, the antimicrobial activity of HL and the complex [CuL(μ-CH 3 COO)] 2 was tested against pathogenic Gram-positive and Gram-negative bacteria and fungi. The synthesized new structure of hydrazone complexed with copper (II) shows antimicrobial activity, and magnetic susceptibility results indicate weak antiferromagnetic coupling between the copper atoms., (Copyright © 2019 Elsevier Inc. All rights reserved.)