A flexible diastereoselective approach to trans-(3S)-hydroxyprolinol derivatives is described, which is based on the samarium diiodide-mediated reductive coupling of the chiral 1-pyrroline N-oxide (nitrone)(S)-10 with carbonyl compounds. The reductive hydroxyalkylation of nitrone 10 with ketones and aromatic aldehydes is highly diastereoselective in establishing the C-2 chiral center of the pyr...

Highly enantioselective 1,3-dipolar cycloaddition reactions of α-substituted diazoacetates are accomplished by catalysis of the chiral oxazaborolidinium ion. Functionalized 2-pyrazolines are synthesized in high to excellent enantiomeric ratios (up to >99 : 1). The synthetic utility of 2-pyrazoline was expanded via preparation of 2,4-diamino ester compounds bearing a chiral quaternary carbon cen...

The loop algebra L(sl2) symmetry is found in a sector of the nilpotent BazhanovStroganov model. The Drinfeld polynomial of a L(sl2)-degenerate eigenspace of the model is equivalent to the polynomial [4, 5, 10–14] which characterizes a subspace with the Isinglike spectrum of the superintegrable chiral Potts model.

Here we report on a nanoscale circular dichroism (CD) imaging for a two-dimensional chiral pair of nanostructures to elucidate the relationship between nanoscale chirality and CD activity. The chiral pair exhibited local ellipticity as high as 42 degrees in the CD signal at the center, with signals of both handedness coexisting in one nanostructure.

The absolute configuration of the chiral center at the C15 position of a novel branched-chain fatty acid derived from a new ceramide isolated from the epiphytic dinoflagellate Coolia monotis was determined to be of R from by reversed-phase HPLC after cleavage to 12-methylpentadecanoic acid and subsequent conversion with the chiral fluorescent reagent, (1R,2R)-2-(2,3-anthracenedicarboximido)cycl...

It is widely accepted that Quantum Chromodynamics (QCD) has phase transitions at high temperature, the nature of which depends on the quark mass, mq. In the limit of mq = 0, QCD has chiral symmetry, SUL(Nf)× SUR(Nf), in the case of Nf flavors, that spontaneously breaks into SUV(Nf) at low temperatures. The chiral condensate, 〈q̄q〉, serves as an order parameter for chiral restoration at high temp...

Go catalytic! A catalytic enantioselective protonation of alkenyl trifluoroacetates was achieved by using an in situ generated chiral tin bromide methoxide as the chiral catalyst in the presence of methanol. Optically active ketones containing a tertiary stereogenic center at the α-position were obtained with enantioselectivities of up to 94 % ee.

A diastereo- and enantioselective aldol reaction between aldehydes and a synthetically useful ketomalonate 1c as a hydrated form was developed, and either anti- or syn-aldol adducts having a chiral tetrasubstituted carbon center were obtained in high enantioselectivities by use of a tetrazole analogue of L-proline (S)-2 or an axially chiral amino sulfonamide (S)-3 as catalyst.

The enantioselective surface chemistry of two chiral alkyl halides, S-1-bromo-2-methylbutane and R-2-bromobutane, have been compared on the naturally chiral Cu(643) surfaces. Temperature programmed reaction spectroscopy was used to quantify the yields of the various decomposition products during heating. A fraction of the adsorbed alkyl bromides desorb intact while the remainder decomposes by d...

We discuss theories with the exceptional centerless gauge group G(2), paying attention to confinement and the pattern of chiral symmetry breaking. Exploiting the Higgs mechanism to break the symmetry down to SU (3), we also present how the familiar features of confinement and chiral symmetry breaking of SU (3) gauge theories reemerge. G(2) gauge theories show up as an unusual theoretical framew...