[Substrate properties of C'-methylnucleoside triphosphates in a reaction of RNA synthesis catalyzed by Escherichia coli RNA-polymerase].

2 theta-C-methyl substituted and phosphonate analogs of UTP were prepared and together with the synthesized earlier 3'-C-methyl-UTP were investigated in the RNA synthesis reaction catalysed by Escherichia coli RNA-polymerase. Substrate properties of UTP analogs were studied in the presence of all natural triphosphates, in the absence of UTP and under conditions of soil substrate reaction. It was shown that UTP(3'CH3) is incorporated into the RNA chain and terminates further RNA elongation.

[Substrate specificity of adenosine deaminase. The role of methyl groups at 2', 3', and 5'-carbon atoms of adenosine].

The substrate specifity of adenosine deaminase has been studied using C'-methyl derivatives of adenosine. On the basis of the correlation revealed between conformations of 2'- and 3'-C-methyladenosine and their substrate properties, a modified stereochemical model is suggested: the enzyme accepts the substrate within a N-type conformational range (4E----4T3----3E) of the furanose ring. The model was analysed in details using a number of C3'-modified adenosines and 5'-C-methyladenosine analogues with D-allo- and L-talo-configuration.

[Derivatives of C-branched monosaccharides studied by 13C NMR].

13C NMR spectra of some 3-C branched D-allofuranoses and D-ribofuranoses were obtained and interpreted. The impact of attaching the alkyl substitute to the monosaccharides on chemical shifting of the adjacent carbon atoms was shown. The experimental data are useful for elucidating structures of analogous compounds by 13C NMR.