trifluoromethylated organic compounds, especially chiral quaternary alcohols bearing trifluoromethyl group are of important intermediates in drugs, agrochemicals and etc.an efficient epoxidation of β-cf3-β,β-disubstituted unsaturated ketones (6) has been developed with environmental benign hydrogen peroxide as the oxidant and f5-substituted chiral quaternary ammonium salt (1g or 5) derived from...

This work was motivated by the unsatisfactory stability of Au(25)(SG)(18) in solution under thermal conditions (e.g. 70-90 °C for DNA melting). Thus, we searched for a better, water-soluble thiol ligand. Herein, we report a one-pot synthesis and investigation of the stability and optical properties of captopril (abbreviated Capt)-protected Au(25)(Capt)(18) nanoclusters. The Au(25)(Capt)(18) (an...

(-)-Gephyrotoxin-223 was formally synthesized from chiral synthon 1 which has been chemoenzymatically synthesized  in the presence  of Candida Antartica lipase.        

in the first part of this work, correlation between optical activity and elements of magnetic susceptibility tensor (mst) for five classes of model small molecules containing a single chiral center has been studied using quantum computational techniques at dft-b3lyp level of theory with 6-311g basis set. several molecular properties are used to reduce the mst elements prior to the examination o...

one-pot, four-component procedure for the synthesis of a small library of new chiral spiro- oxindolopyrrolidines with high regio-, diastereo- (>99:1 dr), and enantioselectivity (up to 80% ee) is described. in this process, the regio- and stereochemical 1,3-dipolar cycloaddition of azomethine ylides, which were generated insitu by the reaction of isatin derivatives and sarcosin,with optically ac...

An efficient one-pot three-component procedure for the synthesis of new chiral spiro-oxindolopyrrolizidines with highly regio-, diastereo-, and enantioselective from 1,3-dipolar cycloaddition of azomethine ylides and optically pure active cinamoyl oxazolidinone are described. The process occurs at room temperature in aqueous ethanol as green solvent and in the absence of any bidentate chelating...

In this paper, the propagation of electromagnetic waves through an infinite slab of uni- or bi- axial chiral medium is analytically formulated for an arbitrary incidence using 4×4 matrix method. In this powerful method, a state vector differential equation is extracted whose solution is given in terms of a transition matrix relating the tangential components of electric and magnetic fields at t...

due to high resolution power of sulfated cyclodextrins (hs-cds), utilization of these selectors for chiral resolution of 7 basic and 2 zwitterionic drugs have been examined. experiments were performed on a hp3dce instrument equipped with an on-column diode array uv absorbance detector. fused silica capillaries with an inner diameter of 50 ?m, an outer diameter of 365 ?m, and a total length of 4...

There is great interest in design and synthesis of small molecules which selectively target specific genes to inhibit biological functions in which particular DNA structures participate. Among these studies, chiral recognition has been received much attention because more evidences have shown that conversions of the chirality and diverse conformations of DNA are involved in a series of importan...

In three-dimensional QED with a Chern–Simons term we study the phase structure associated with chiral-symmetry breaking in the framework of the Schwinger–Dyson equation. We give detailed analyses on the analytical and numerical solutions for the Schwinger–Dyson equation of the fermion propagator, where the nonlocal gauge-fixing procedure is adopted to avoid wavefunction renormalization for the ...