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...

chiral pyrrolidines and pyrrolizidines with spirooxindole ring systems are the central skeletons for numerous alkaloids and pharmacologically important compounds. gelesmine, pseudotabersonine, formosanine, isoformosanine, morroniside and mitraphylline are some of the alkaloids containing spirooxindole ring systems. derivatives of spirooxindole find very wide biological applications as anti micr...

Mandelic acids are prototypic chiral molecules where the sensitivity of crystallized forms (enantiopure/racemic compound/polymorphs) to both conditions and substituents provides a new insight into the factors that may allow chiral separation by crystallization. The determination of a significant number of single crystal structures allows the analysis of 13 enantiopure and 30 racemic crystal str...

the distribution behavior of ofloxacin enantiomers was examined in the aqueous and organic solvent of a two-phase system containing chiral selector l-tartarate. the effect of extraction equilibrium time, buffer ph, organic solvents and length of alkyl chain of l-tartarate on the partition coefficients and enantioselectivity of racemic ofloxacin were investigated, respectively. the l-tartarate f...

It is argued that the presumed mesophase theory of liquid crystals, which has evolved over the preceding century and is currently in vogue, is not only largely conjectural but also ignores fundamental theoretical principles and key experimental observations. Essentially, it is unsupported by hard experimental evidence, and the view that a large collection of molecules can remain both ordered an...

Abstract We explore the properties of polynomial Lagrangians for chiral p -forms previously proposed by last named author, and in particular, provide a self-contained treatment symmetries equations motion that shows great economy simplicity this formalism. further use analogous techniques to construct democratic general where electric magnetic potentials appear on equal footing as explicit dyna...

The role of cut-off and dimensional regularizations is discussed in the context of obtaining a renormalized nucleon-nucleon potential from the chiral Lagrangian formulation of the effective field theory due to Weinberg. Both types of renormalizations are performed for the sum of an attractive delta function and its derivatives. The equivalence between the two forms of regularizations can be est...