Products 3a Research Articles

Chiral Bicyclic Imidazole-Catalyzed Direct Enantioselective C -Acetylation of Indolones

Chiral Bicyclic Imidazole-Catalyzed Direct Enantioselective <i>C</i> -Acetylation of Indolones

A facile one-pot, solvent-free synthesis of new pyrazolone-1,3-dithiolan hybrids through the reaction between 2-pyrazoline-5-ones, CS2, and α-chloroacetaldehyde

An efficient one-pot, solvent-free synthesis of pyrazolone-1,3-dithiolan hybrid derivatives from the reaction of 2-pyrazoline-5-ones, carbon disulfide, and α-chloroacetaldehyde in the presence of triethylamine is reported. Two possible stereoisomers (E and Z) can be formed in this reaction. The structures of the produced 5-pyrazolone-1,3-dithiolan derivatives are determined based on their IR, 1H NMR, 13C NMR, and mass spectroscopic data. The 4-hydroxy-1,3-dithiolan moieties in hybrid products 2a and 2 g are readily converted to the related dehydrated products 3a and 3 g, respectively.

Reversible Redox Chemistry of Anionic Imidazole-2-thione-Fused 1,4-Dihydro-1,4-diphosphinines.

Anionic 1,4-dihydro-1,4-diphosphinines were synthesized from tricyclic 1,4-diphosphinines and isolated as blue powdery salts M[2a–2c]. Reaction of solutions of these monoanions with iodomethane led to P-methylated compounds 3a–3c. An oxidation/reduction cycle was examined, starting from solutions of K[2a] via P–P coupled product 4a and back to K[2a], and the recyclability and redox chemistry of this cycle were confirmed by experimental and simulated cyclic voltammetry analysis, which is proposed as a potential 2-electron cathode for rechargeable cells. TD-DFT studies were used to examine species that might be involved in the process.

Synthesis, molecular docking, and biological evaluation of 5‐alkyl(aryl)‐2‐isobutylthiazole derivatives: As α‐amylase, α‐glucosidase, and protein kinase inhibitors

AbstractA series of 18 biologically active C5‐arylated‐2‐isobutylthiazole derivatives that were synthesized by Pd‐NHC complexes [Pd(μ‐Cl)Cl (NHC)]2, NHC = SIXyl, 2), (LCl2Pd‐NHC, L = PPh3, 3), (LCl2Pd‐NHC, L = Py, 4), (LCl2Pd‐NHC, L = 3‐CHO‐Py, 5) catalyzed C‐H bond activation reactions. The catalytic activity of Pd‐NHC complexes was examined on the C‐H bond activation reaction of 2‐isobutylthiazole. All Pd‐NHC complexes were characterized by 1H nuclear magnetic resonance specroscopy (NMR), 13C NMR, fouirer transform infrared spektroscopy (FTIR), quadrupole‐time of flying‐liquit cromotagraphy/mass spektroscopy (Q‐TOF‐LC/MS), gas chromatography–mass spectrometry (GCMS), and melting point detection technique. The physicochemical properties, pharmacokinetics, and drug‐likeness were calculated by SwissADME. PkCSM database was used to calculate toxicities profile. All the products (6a–6s) were additionally assessed in vitro for their antidiabetic potential using α‐amylase and α‐glucosidase inhibitory activities. The protein kinase activity was performed to evaluate their anticancer activities. All the compounds possess drug‐like characters as they followed Lipinski's rule of five (RO5). Almost all the compounds showed no to fewer toxicities. In addition, other than the compounds, that is, 6a, 6b, 6c, 6m, 6n, 6p, and 6s, the rest of the compounds showed good α‐glucosidase inhibitory potential (IC50 7.17 ± 0.201 to 74.08 ± 0.244 μg/ml) when compared with acarbose standard (IC50 16.59 ± 0.135 μg/ml). All compounds had moderate to good inhibitory potential against the α‐amylase enzyme, with IC50 values ranging from 12.00 ± 0.289 to 76.15 ± 0.477 μg/ml. Eleven analogs (6e, 6f, 6g, 6h, 6j, 6k, 6l, 6n, 6o, 6p, and 6r) showed good to moderate activity. Seven analogs (6a, 6b, 6c, 6d, 6i, 6m, and 6s) showed no α‐amylase inhibitory activity. The protein kinase inhibition potential was determined for the first time, and the compounds 6d, 6e, 6f, 6h, 6k, 6p, and 6r depicted activity with the zone of inhibition in the range of 9 ± 1.3 to 19 ± 1.5 mm. The ligands and active site binding interactions of α‐glucosidase, α‐amylase, and protein kinase enzymes were also studied using molecular modeling.

Diarylation of N- and O-nucleophiles through a metal-free cascade reaction

Diarylation of N- and O-nucleophiles through a metal-free cascade reaction

Nickel-Catalyzed Enantioselective C(sp 3 )–H Arylation of Ketones with Aryl Ethers via Selective C Ar –O Cleavage to Construct All-Carbon Quaternary Stereocenters

Nickel-Catalyzed Enantioselective C(sp ³ )–H Arylation of Ketones with Aryl Ethers via Selective C _Ar –O Cleavage to Construct All-Carbon Quaternary Stereocenters

General and Efficient C–P Bond Formation by Quantum Dots and Visible Light

General and Efficient C–P Bond Formation by Quantum Dots and Visible Light

Exploration of Oxidative Ritter-Type Reaction of α-Arylketones and Its Application for the Collective Total Syntheses of Erythrina Alkaloids

Exploration of Oxidative Ritter-Type Reaction of α-Arylketones and Its Application for the Collective Total Syntheses of <i>Erythrina</i> Alkaloids

Chiral Sulfide/Phosphoric Acid Cocatalyzed Enantioselective Intermolecular Oxysulfenylation of Alkenes with Phenol and Alcohol O -Nucleophiles

Chiral Sulfide/Phosphoric Acid Cocatalyzed Enantioselective Intermolecular Oxysulfenylation of Alkenes with Phenol and Alcohol <i>O</i> -Nucleophiles

Generation of boryl-nitroxide radicals from a boraalkene via the nitroso ene reaction.

Examples of isolated boron substituted nitroxide radicals are rare. The reaction of the reactive cyclic boraalkene 3 with nitrosobenzene yields a mixture of the [2 + 2] cycloaddition product 4a, the B-nitroxide radicals 5a and 6a and the azoxybenzene co-product 7avia a bora nitroso ene reaction pathway, the boron analogue of the nitroso ene reaction. The products were separated by flash chromatography, and the B-nitroxide radicals were characterized by X-ray diffraction and EPR spectroscopy. Radical 5a was shown to be a hydrogen atom abstractor. Both the B-nitroxide radicals are more easily oxidized compared to e.g. TEMPO, as shown by cyclic voltammetry.

Synthesis of 4-((4-(4-nitrophenoxy)phenyl)diazenyl)benzene-1,3-benzoate:Experimental, DFT and, DNA binding investigation through spectral and molecular docking studies

Pharmacists and other researchers have always been fascinated by the DNA sensing evaluation. This piece of work emphasizes on the synthesis, characterization and DNA sensing of a novel azo ester (N = N, -COO) molecule. The product (1A) was synthesized employing a typical esterification reaction between previously reported resorcinol coupled azo dye and Benzoyl chloride. The structural interpretation of the synthesized ester was done by FT-IR (Fourier transform infrared), NMR (Nuclear magnetic resonance), UV/VIS (ultraviolet–visible spectroscopy), and single crystal X-ray diffraction studies. XRD analysis elucidated the Ester 1A to be in the Monoclinic system with P21/n space group. The DFT simulation experiments were also examined to investigate the structural implications of the resulting product. The higher softness (S), electrophilicity index (ω) and electronegativity (χ) values demonstrated greater polarizability and reactive nature of the compound. Further, wet and silico binding methods were employed to examine the DNA sensing ability of the synthesized molecule with SS-DNA. UV/VIS spectroscopy and hydrodynamic measurements (Viscosity) suggested Groove binding mode of interaction with a moderate value of binding constant, which was further confirmed by molecular docking techniques.

Nickel-Catalyzed Regiodivergent Asymmetric Cycloadditions of α,β-Unsaturated Carbonyl Compounds

Nickel-Catalyzed Regiodivergent Asymmetric Cycloadditions of α,β-Unsaturated Carbonyl Compounds

A base-controlled switch of SO2 reincorporation in photocatalyzed radical difunctionalization of alkenes

A base-controlled switch of SO2 reincorporation in photocatalyzed radical difunctionalization of alkenes

A relay catalysis strategy for enantioselective nickel-catalyzed migratory hydroarylation forming chiral α-aryl alkylboronates

A relay catalysis strategy for enantioselective nickel-catalyzed migratory hydroarylation forming chiral α-aryl alkylboronates

Asymmetric Henry Reaction of Nitromethane with Substituted Aldehydes Catalyzed by Novel In Situ Generated Chiral Bis(β-Amino Alcohol-Cu(OAc)2·H2O Complex

Novel chiral thiophene-2,5-bis(β-amino alcohol) ligands (L1–L5) were designed and synthesized from thiophene-2,5-dicarbaldehyde (3) with chiral β-amino alcohols (4a–e) in 4 steps with overall 23% yields. An in situ generated L-Cu(OAc)2·H2O catalyst system was found to be highly capable catalyst for the asymmetric Henry reaction of nitromethane (7) with various substituted aromatic aldehydes (6a–m) producing chiral nitroaldols product (8a–m) with excellent enantiomeric purity (up to 94.6% ee) and up to &gt;99% chemical yields. 20 mol% of L4-Cu(OAc)2 catalyst complex in EtOH was effective for the asymmetric Henry transformation in 24 h, at ambient temperature. Ease of ligand synthesis, use of green solvent, base free reaction, mild reaction conditions, high yields and excellent enantioselectivity are all key factors that make this catalytic system robust and highly desirable for the access of versatile building block β-nitro alcohol in practical catalytic usage via asymmetric Henry reaction.

Palladium(0) Catalyzed Synthesis of (E)-4-Bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline Derivatives via Suzuki Cross-Coupling Reaction: An Exploration of Their Non-Linear Optical Properties, Reactivity and Structural Features.

A series of (E)-4-bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline analogs synthesized in considerable yields through Suzuki cross-coupling reactions. Various electron donating and withdrawing functional moieties were successfully incorporated under the employed reaction conditions. Reaction of 4-bromo-2-methylaniline (1) with 3-bromothiophene-2-carbaldehyde (2b) in the existence of glacial acetic acid, provided (E)-4-bromo-N-((3-bromothiophen-2-yl)methylene)-2-methylaniline (3b) in excellent yield (94%). Suzuki coupling of 3b with different boronic acids in the presence of Pd(PPh3)4/K3PO4 at 90 °C led to the synthesis of the monosubstituted and bisubstituted products 5a–5d and 6a–6d in moderate yields (33–40% and 31–46%, respectively). Density functional theory (DFT) investigations were performed on different synthesized analogues 5a–5d, 6a–6d to determine their structural characteristics. The calculations provide insight into the frontier molecular orbitals (FMOs) of the imine-based analogues and their molecular electrostatic potential (MESP). Reactivity descriptors like ionization energy (I), electron affinity (A), chemical hardness (ƞ) and index of nucleophilicity have been calculated for the first time for the synthesized molecules.

A neutral germanium/phosphorus frustrated Lewis pair: Synthesis and reactivity

A novel germinal germanium/phosphorus frustrated Lewis pair, Cl3GeCH2PtBu21, was prepared through the metathesis reaction of tBu2PCH2Li with tetrachlorogermanium. This neutral germanium-based frustrated Lewis pair 1 exhibits higher reactivity toward a series of small molecules. When 1 was treated with an excess amount of tetrachloromethane (2.3equiv) yielding a zwitterionic adduct 2, Cl4GeCH2P(Cl)tBu2. The cycloaddition of dimethyl but-2-ynedioate with 1 was took place smoothly at room temperature, and afforded a zwitterionic cyclic vinyl 3 in good yields. The reaction of 1 with furan-2,5-dione has also been performed giving the corresponding cycloaddition 4 in high yields. The additions of C=Ch (Ch = O, and S) units involving 1-isocyanato-4-methylbenzene and isothiocyanatobenzene with 1 have been also carried out at ambient temperature in which the five-membered GeCPCO(S)-ring products 5a and 5b were furnished, respectively. All these above-mentioned compounds 1-5 were fully characterized by multinuclear NMR spectroscopy, high-resolution mass spectrometry (HRMS), and the structures of 1 and 3 were also determined by single-crystal X-ray diffraction.

Asymmetric syntheses of four stereoisomers of 13-hydroxy-14-methylhexadecanoic acid as potential antibacterial agents.

The first total syntheses of four stereoisomers of 13-hydroxy-14-methylhexadecanoic acid have been accomplished. Central to this strategy are asymmetric alkynylation of aldehyde, acid-catalyzed lactonization, the selective protection of primary alcohol and Wittig reaction. The product 1a was obtained in 17 steps in 2% overall yield. Moreover, these synthetic chiral hydroxy fatty acids 1a-1d are valuable for the development of antibacterial agents.

Visible-light photoredox-catalyzed selective carboxylation of C(sp3)−F bonds with CO2

Visible-light photoredox-catalyzed selective carboxylation of C(sp3)−F bonds with CO2

Switchable and Scalable Heteroarylation of Primary Amines with 2-Chlorobenzothiazoles under Transition-Metal-Free and Solvent-Free Conditions.

2-Aminobenzothiazoles comprise a valuable structural motif, which prevails in versatile natural products and biologically active compounds. Herein, a switchable and scalable C-N coupling protocol was developed for the synthesis of these compounds from 2-chlorobenzothiazoles and primary amines. Gratifyingly, this protocol was achieved under transition-metal-free and solvent-free conditions. Moreover, introducing an appropriate amount of NaH completely switched the selectivity from mono- toward di-heteroarylation, and further investigations provided a rationale for this new finding. Furthermore, gram-scale synthesis of representative products 3a and 4a was realized by applying operationally simple and glovebox-free procedures, which revealed the practical usefulness of this work. Finally, evaluation of the quantitative green metrics provided evidence that our protocol was superior over the literature ones in terms of green chemistry and sustainability.