Analysis of syn and anti orientations of guanine residues along the skeleton of known G-quadruplex structures enabled us to develop a formalism, which can be used to design new G-quadruplex topologies with desired features in a rational way. Prediction of folding with predicted topology has been experimentally verified and confirmed by synthesis of oligonucleotide, whose 3D structure has been determined by NMR in solution.
COBISS.SI-ID: 4320026
New P-stereogenic 1,2-bis[(o-iso-propoxyphenyl)(phenyl)phosphino] ethane ligand (i-Pr-SMS-Phos) was prepared and tested in Rh-catalyzed asmmetric hydrogenation of olefins. The study of the catalytic profile of Rh-(iPr-SMS-Phos) under different reaction variables was as well carried out. NMR studies of hydrogenation of MAC with this catalyst showed for the first time that the more reactive catalyst-substrate adduct is formed in higher amount than the less reactive adduct in contrary to the usual trend in such catalysis accounting for the obtained higher reaction rates and enantioselectivities.
COBISS.SI-ID: 4320282
Exchange of the Cys-S-S-Cys bridge by the His-Cu(II)-His motif is very promising, because the resulting complexes retain topological similarity to the native S-S bridged AVP and OXT at pH values corresponding to the physiological pH. The detailed potentiometric and spectroscopic studies on the Cu(II) complexes of [His(1,6)]OXT, together with high resolution 3D structures of Cu(II) complexes with [His(1,6)]OXT and [His(1,6)]AVP analogues are reported.
COBISS.SI-ID: 4171546
The conformational preorganization and anion-induced conformational changes of indole-based receptors functionalized with an amide group at the 2-position and a variety of amide, urea and thiourea moieties at the 7-position have been studied by the means of NMR spectroscopy. NOE experiments showed that anti–anti orientation across C2–C2a and C7–N7a bonds is preferred for receptors in acetone solution in the absence of anions. NOE enhancements in the presence of anions revealed that anion–receptor complexes favour the syn–syn conformation of the C2 and C7 substituents.
COBISS.SI-ID: 4211482
Interaction between the Zn(2+) ions and the histidine analogues of oxytocin and arginine-vasopressin were studied by potentiometric methods for determination of the stoichiometry of the complexes formed and the calculation of their stability constants. The NMR measurements revealed detailed structures of the complexes and confirmed the binding mode at physiological pH.
COBISS.SI-ID: 4178458