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A highly-efficient and practical method for S-alkylation of arylthioureas was reported. Using tetraalkylammonium salts as alkylation reagents, a series of 68 S-substituted aryl-isothioureas were obtained in good to excellent yields under transition-metal-free conditions. The protocol features simple performance, broad functional group tolerance, good to excellent yields, and easily available starting materials, showing potential synthetic value for the preparation of diverse biologically or pharmaceutically active compounds.

An iodine-catalyzed synthesis of benzoazole-substituted thioenamines in a one-pot manner was reported. Using 2-aminothiophenols (or 2-aminophenols or 1,2-phenylenediamines), tetramethylthiuram disulfide (TMTD), and enamines (mainly indoles) as starting materials, the target C(sp

A metal-free Cs2CO3-promoted hydrothiolation of alkynes with aryl thioureas for stereoselective synthesis of (Z)-vinyl sulfides has been reported. Vinyl thioethers were obtained without a metal catalyst in good yields via anti-Markovnikov and cis addition. The protocol features a broad substrate scope of the starting materials, high atom economy, good yields, and exclusive stereoselectivity, showing potential synthetic value for the synthesis of a diversity of (Z)-vinyl thioethers.

An efficient synthesis of a variety of 1,2-disubstituted indoles from 2-ethynylanilines was developed. Using 2-ethynylanilines and benzaldehydes as starting materials, the target products (1,2-disubstituted indoles) were obtained smoothly through condensation, reduction, and subsequent cyclization. Various functional groups attached to the aryl ring of 1,2-disubstituted indoles were well tolerated. The protocol features easy performance, easily available starting materials, good yield, and a broad substrate scope, showing potential synthetic value for the preparation of a variety of biologically or pharmaceutically active compounds.

A metal-free Cs

In the present work, 103 novel acyclic nucleosides were designed, synthesized, and evaluated for their anticancer activities

To investigate the influence of bridgehead-C functionality in diiron dithiolate complexes on the molecular structure and electrocatalytic properties of [FeFe]-hydrogenase models, three new bridgehead-C-functionalized model complexes 1–3 have been synthesized and structurally characterized. Treatments of parent complex [(μ-SCH2)2CHCO2H][Fe2(CO)6] (A) with the esterification agents o-MeC6H4OH, p-ClC6H4OH, or p-HOC6H4CHO in the presence of 4-dimethylaminopyridine and dicyclohexylcarbodiimide in CH2Cl2 at room temperature resulted in formation of [(μ-SCH2)2CHCO2R][Fe2(CO)6] (R = o-MeC6H4–, 1; p-ClC6H4–, 2; p-OHCC6H4–, 3) in 53–55% yields. The new complexes 1–3 were characterized by elemental analysis, IR and NMR spectroscopy, and especially determined by X-ray crystallography. The electrochemical properties of 1–3 and the electrocatalytic H2 evolution catalyzed by 1 have been investigated by cyclic voltammetry, where 1 is a catalyst for HOAc proton reduction to H2 under electrochemical conditions.

A classical but new kinetic equation to estimate activation energies of various hydride transfer reactions was developed according to transition state theory using the Morse-type free energy curves of hydride donors to release a hydride anion and hydride acceptors to capture a hydride anion and by which the activation energies of 187 typical hydride self-exchange reactions and more than thirty thousand hydride cross transfer reactions in acetonitrile were safely estimated in this work. Since the development of the kinetic equation is only on the basis of the related chemical bond changes of the hydride transfer reactants, the kinetic equation should be also suitable for proton transfer reactions, hydrogen atom transfer reactions and all the other chemical reactions involved with breaking and formation of chemical bonds. One of the most important contributions of this work is to have achieved the perfect unity of the kinetic equation and thermodynamic equation for hydride transfer reactions.

Zinc 5- aminosalylicylate (5-ASZ), a new creative medicine, can react with serum albumin to form a complex. Based on this, a new method for the determination of proteins by synchronous fluorescence spectra under simulated physiological conditions was established using 5 - ASZ as a fluorescence probe. The spectral characterization and intensity of synchronous fluorescence were related to the value of deltalambda, reaction medium and reaction temperature, and so on. On basis of these, eperimental results show that, under the optimum conditions, the synchronous fluorescence intensity of the system is in proportion to the concentration of protein in the range of 1.66-496.8 microg x mL(-1) for human serum albumin (HSA). The detection limit was 0.88 microg x mL(-1) (n = 11) for HSA. On basis of these it had been applied to the determination of proteins in human serum, urine and spit samples with satisfactory results, the recovery was within the range of 98.0%-103.8%. Results suggested that the method possessed easy of implementation, rapidity, high sensitivity, broad linear range, and better RSD and recovery, and so on, and the method was employed directly to determine the total proteins in samples, which results were satisfactory.

Crystals of the title adduct, C(10)H(8)N(2)·2C(3)H(3)NO(2), were obtained from a methanol/water solution of cyano-acetic acid and 4,4'-bipyridine at room temperature. In the crystal structure, cyano-acetic acid and centrosymmetric 4,4'-bipyridine mol-ecules are linked by O-H⋯N hydrogen bonds to form three-component supra-molecular adducts. The acidic H atom is almost midway between the O and N atoms of the cyano-acetic acid and bipyridine mol-ecules, with O-H and N-H distances of 1.19 (3) and 1.39 (3) Å, respectively, so that the H-atom transfer is best regarded as partial. The three-component adducts are further inter-connected with neighboring mol-ecules by weak inter-molecular C-H⋯O and C-H⋯N hydrogen bonds and by π-π stacking inter-actions [centroid-centroid distance = 3.7200 (11) Å] to generate a three-dimensional supra-molecular structure.

In the title compound, C(13)H(14)N(2)·2C(8)H(6)O(5), which crystallized in the monoclinic C2/c space group, the 1,3-bis-(4-pyrid-yl)propane mol-ecules and 2-hydr-oxy-1,4-benzene-dicarboxylic acid mol-ecules are alternately linked by O-H⋯N and O-H⋯O hydrogen bonds into herringbone/zigzag chains.

In the title compound, C16H11F3O, the dihedral angle between the two rings is 48.8 (2)°. The crystal packing exhibits no classical intermolecular interactions between the molecules.