A Viedma ripening route to an enantiopure building block for Levetiracetam and Brivaracetam

A simple route to enantiomerically pure (S)-2-aminobutyramide – the chiral component of the anti-epileptic drugs Levetiracetam and Brivaracetam has been developed. This approach is based on the rational design and application of a Viedma ripening process. The practical potential of the process is demonstrated on a large scale.

Synthesis and Investigation of Polymerization Properties of Methacrylic Monomers with Chiral Fragments

Methacrylic monomers containing chiral moieties and azobenzene derivatives were synthesized. As the chiral component was used menthol. The polymerization properties of monomer (5-methyl-2- (1-methyl)cyclohexanol with azomonomers were studied and the reactivity ratios as well as parameters Q and e characterizing the activity of the obtained monomers have been calculated. On basis of the synthesized monomers were synthesized chiral-photochromic copolymers and their absorption spectra were studied. It was shown that in the copolymers absorption spectra the absorption maxima are in the wavelength region of 340-360 nm and correspond to trans-form of azo fragments.

Chiral symmetry breaking as a geometrical process

This paper is an extension for spinor fields the recently developed Dynamical Bridge formalism which relates a linear dynamics in a curved space to a nonlinear dynamics in Minkowski space. This leads to a new geometrical mechanism to generate a chiral symmetry breaking without mass, providing an alternative explanation for the absence of right-handed neutrinos. We analyze a spinor field obeying the Dirac equation in a curved space which is constructed by its own current. This way, both chiralities of the spinor field satisfy the same dynamics in the curved space. Afterward, the dynamical equation is re-expressed in terms of the flat Minkowski space and then each chiral component behaves differently. The left-handed part of the spinor field satisfies the Dirac equation while the right-handed part is trapped by a Nambu–Jona-Lasinio type potential.

MIXING EFFECTS IN SUPERNOVA PROCESSES WITH RIGHT-HANDED NEUTRINOS

The right-handed chiral component of the Dirac neutrino field in a dense medium is derived for two generation mixing. As an application, the modification factor on the luminosity of a supernova core is given for ν+ emission by neutrino-magnetic-moment and neutrino-charge-radius interactions.