An efficient method for palladium-catalyzed homocoupling reaction of terminal alkynes in the synthesis of symmetric diynes is presented. The results showed that both Pd(OAc)(2) and CuI played crucial roles in the reaction. In the presence of 2 mol % Pd(OAc)(2), 2 mol % CuI, 3 equiv of Dabco, and air, homocoupling of various terminal alkynes afforded the corresponding symmetrical diynes in moder...

The α-arylation of enolizable aryl ketones can be carried out with aryl halides under transition-metal-free conditions using KOtBu in DMF. The α-aryl ketones thus obtained can be used for step- and cost-economic syntheses of fused heterocycles and Tamoxifen. Mechanistic studies demonstrate the synergetic role of base and solvent for the initiation of the radical process.

An intra-molecular Claisen-like cyclization of ethyl 2-acet-oxy-4,4-dimethyl-1-(3-methyl-but-2-en-yl)cyclo-hex-2-enecarboxylate followed by dialkyl-ation yielded the bicyclic title compound, C(23)H(26)O(4). In both of the fused six-membered rings exist fragments of four atoms which are planar, whereas the remaining two atoms deviate by up to 0.682 (3) Å on one side of the plane of the ring cont...

Enzymes are proficient catalysts that enable fast rates of Michaelis-complex formation, the chemical step and products release. These different steps may require different conformational states of the active site that have distinct binding properties. Moreover, the conformational flexibility of the active site mediates alternative, promiscuous functions. Here we focused on the lactonase SsoPox ...

OBJECTIVES To compare the microbiological efficacy, turnaround time, cost, convenience, and patient and user tolerance of Tristel Trio Wipes, PeraSafe solution and Cidex OPA solution for the high-level disinfection of flexible nasendoscopes. METHODS Flexible nasendoscopes were used in routine clinical encounters. They were then disinfected with one of the three disinfectant methods. Surveilla...

A novel method for palladium-catalyzed cyanation of aryl bromides promoted by low-level tri-n-butyltin chloride or cyanide is described. The method features low catalyst loading and mild reaction conditions. KCN is used as the cyanide source. Only trace levels of the tri-n-butyltin compound are required to achieve high conversion and yield in the cyanation of aryl bromides, iodides, and triflates.

High alcohol consumption is an important risk factor for chronic disease and liver degeneration. Paraoxonase (PON1) and arylesterase (AE) are functions of the enzyme paraoxonase, which is synthesised by the liver. Paraoxonase circulates in plasma bound to HDL and hydrolyses lipid peroxides, protecting lipoproteins against oxidative modification. It has been shown that excessive alcohol consumpt...

Based on the dramatic accelerating effect of 2-aminophenol, three ligands derived from 2-aminophenol were developed. Copper-catalyzed coupling reaction of nitrogen-containing nucleophiles with aryl bromides was efficiently carried out under mild conditions using 1,2,3,4-tetrahydro-8-hydroxyquinoline as a novel, simple, and versatile ligand.

ITALIC! Ochrobactrum anthropiFRAF13 was isolated from farmland soil in Jersey Village, Texas. FRAF13 is a bacterial microorganism with broad antibiotic resistance that possesses a number of metal-dependent β-lactam enzymes with secondary phosphotriesterase activity that can initiate the breakdown of organophosphate compounds.

A genetically engineered Escherichia coli cell expressing both organophosphorus hydrolase (OPH) and a cellulose-binding domain (CBD) on the cell surface was constructed, enabling the simultaneous hydrolysis of organophosphate nerve agents and immobilization via specific adsorption to cellulose. OPH was displayed on the cell surface by use of the truncated ice nucleation protein (INPNC) fusion s...