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1. Preliminary heat treatment of an applied Co carbonyl catalyst with synthesis gas at 150°C and addition of CoO result in an increase in activity. 2. Preliminary heat treatment of the Co carbonyl catalyst in a medium of different gases (CO, H2, CO + H2, Ar) results in a change in the selectivity of synthesis of hydrocarbons from CO and H2. 3. IR spectroscopy showed that CO groups which absorb in the high-frequency region of the spectrum are desorbed first with the formation of unstable complexes in carbonyl complexes applied on aluminosilicate during heat treatment. Partial regeneration of the complexes is possible in a CO + H2 atmosphere.

By means of H1 and P31 spin-lattice relaxation and atom-atomic potentials method it is shown that in aquous solution the ATP gamma-p-azidoanilide--Mn2+ complex occurs mainly as a mixture of two conformers in the ratio of 60:40. They both possess folded conformations with distances between aromatic rings 5-6 A, and adenine residue anti-oriented, the ribose and triphosphate chain conformations are 3E and gg, g'g', g'g', respectively, in the major conformer, and 2E and g'g', g'g', g'g' in the second conformer. Mn2+ ion forms 2-3 complexes with each conformer (the cation being differently coordinated) by substituting phosphoryl oxygens or N7 atoms of adenine for two water molecules in the hydration shell of the cation. Magnesium ion forms inner-sphere complexes with two out of four ion-coordination centres (P alpha, P beta, P gamma, N7(A] and outer-sphere complexes with two other centres.

It is shown that in slightly acidic solution (pH approximately 5.3) reagent CIRCH2NHpT(CT)6 (RCl = -C6H4-N(CH3)CH2CH2Cl) modifies a double-stranded DNA fragment (120 b. p.) containing A(GA)6.T(CT)6 sequence at a single nucleotide residue, viz. G29 located near to this sequence in the DNA chain. The location of this modification point suggests formation of a triple-stranded reactive complex with parallel orientation of the pyrimidine oligonucleotide moiety of the reagent and pyrine sequence of the target DNA. Analysing the modification extent dependence of the reagent concentration the association constant Kx between the reagent and DNA was calculated (Kx = (0.95 +/- 0.03).10(5) M-1, 25 degrees C, pH = 5.3, [NaCl] = 0.1 M). The modification by the reagent ClRCH2NHpT(m5CT)6 has the same quantitative characteristics as in the case of ClRCH2NHpT(CT)6.

The alkylation of the cell biopolymers (RNA, DNA, proteins) by reagents Tp'(Et)Tp'(Et)Tp'(Et)TpU(CHRCl) (1) Tp'(Et)Tp''(Et)Tp'(Et)TpU(CHRCl) (2) Tp''(Et)Tp'(Et)Tp''(Et)TpU(CHRCl) (3) Tp''(Et)Tp''(Et)Tp''(Et)TpU(CHRCl) (4) Tp(Et)Tp(Et)Tp(Et)TpU(CHRCl) (5) Tp(Et)Tp(Et)Tp(Et)Tp(Et)U(CHRCl) (6) TpTpTpTpU(CHRCl) (7) where (CHRCl) is the residue of 2',3'-O-[4-N-(2-chloroethyl)-N-methylamino]-benzylidene has been investigated in the case of the ascite carcinoma Krebs-2. p' and p" designate the enantiomeric configurations at the internucleotide phosphorus atoms of the triester fragment--Tp(Et)T--, and p designates the racemic mixture. Completely and partly ethylated reagents (1)-(6) have been found to bind to the cells 4-15 fold more effectively than the diester derivative. The concentration of reagents (1)-(6) in the cells is 2-7 fold higher than in the external medium. Among the diastereomers (1)-(4) reagent (4) with the p"-configuration is the most efficient in binding with the cells 2-3 fold more efficient than reagents (1)-(3). The main targents of modifications performed in the cells by means of reagents (1)-(7) have been established. These are RNA, DNA and proteins. The share of the reagents which react with nucleic acids increases from 45% [reagent (1)] to 80% [reagent (4)], and that reacting with proteins decreases from 50 to 20% correspondingly. Reagent (4) with the p" configurations at phosphotriester fragments alkylates nucleic acids most effectively among the phosphotriester diastereomers (1)-(4): 11-fold more efficient than reagent (1) with configuration p'. The extent of modification of poly(A)+-tracts of m-RNA by reagent (4) in comparison with reagent (1) is 50-fold higher.

Bullous dermatoses affecting oral mucosa are autoimmune diseases in the majority of cases. The most common diseases in this group are pemphigus vulgaris, bullous pemphigoid, lichen planus. In the early stages of bullous dermatoses, especially for isolated lesions of the oral mucosa, prompt diagnosis is not always possible requiring an interdisciplinary approach to the differential diagnosis.Буллезные дерматозы, при которых поражается слизистая оболочка рта (СОР), в большинстве случаев являются аутоиммунными заболеваниями. Наиболее распространенные заболевания этой группы - вульгарная пузырчатка, буллезный пемфигоид, плоский лишай. На ранних стадиях пузырных дерматозов, особенно при изолированном поражении СОР, диагноз не всегда удается поставить своевременно; требуется междисциплинарный подход к дифференциальной диагностике.

The cobalt(II) tetracarboxyphthalocyanine-deoxyribonucleotide pd(TCTTCCCA) conjugate was synthesized. The phthalocyanineN-succinimide ester prepared from phthalocyanine using DCC was mixed in DMF with an aqueous solution of the oligonucleotide bearing a 1,3-diaminopropane linker at the 5′-phosphate. The resulting conjugate was tested in the intraduplex reaction with target 14-mer and 22-mer oligonucleotides containing conjugate-complementary sequences. In the presence of O2 and a thiol (2-mercaptoethanol or DTT), as a coupled reducer, or H2O2, sequence-specific DNA modification was observed that caused the cleavage of the target upon treatment with piperidine.