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The antimicrobial activity of new meso-tetrakis(N-methyl-6-quinolinyl)-substituted porphyrins and meso-tetrakis(N-methyl-6-quinolinyl)-substituted chlorins is described. The dark toxicity and photosensitising potentials of free-base (TQP and TQC) and its Sn(IV)-complexes [(TQP)Sn(IV) and (TQC)Sn(IV)] were tested on Gram-positive (Staphylococus aureus), Gram-negative (Escherichia coli and Pseudomonas aeruginosa) bacteria and two species of yeasts (Candida albicans and Rhodotorula bogoriensis). The results described in this paper show that TQP and (TQP)Sn(IV) did not inhibit the growth of S. aureus in the dark, but efficiently photosensitize the inactivation of this Gram-positive bacteria. These porphyrins have no appreciable photosensitizing activity towards Gram-negative bacteria. However, (TQP)Sn(IV) shows high dark toxicity against E. coli and P. aeruginosa. The free-base derivatives demonstrated dark activity only in the case of P. aeruginosa. We suppose that these meso-tetrakis(N-methyl-6-quinolinyl)-substituted porphyrins can bind to the Gram-negative bacteria outer membrane receptors that transported vitamin B12. The meso-substituted chlorins TQC and (TQC)Sn(IV) have shown similar efficiency in the dark- and photoinactivation of S. aureus. They revealed a middle level of dark toxicity towards Gram-negative bacteria. The Sn(IV)-complex of chlorin in comparison with free base and metalloporphyrins are more effective in photoinactivation of Gram-negative bacteria. Yeasts, such as Candida albicans and Rhodotorula bogoriensis are more sensitive to photodynamic inactivation as bacterial cells. The effects of (TQP)Sn(IV) and (TQC)Sn(IV) are more expressed than effects of free bases.

The vapor-phase oxidation of mixtures of propylene glycol with methanol and ethanol to methyl and ethyl lactate, respectively, on supported CeO2/Al2O3 catalyst with 10 wt.% CeO2 content was studied. The steel flow reactor with a fixed catalyst bed (4 cm3) was used. 20 wt.% solution of propylene glycol in alcohol was fed to the reactor inlet by Waters 950 pump at LHSV= 0.5-0.8 h-1. Reaction temperature and pressure were varied in the interval of 190-250 0C and 1.3-1.8 bars respectively. Compressed air was given to the reactor inlet at the molar ratio of propylene glycol/O2 = 1. The reaction products were analyzed using gas chromatography (Agilent 7820A) and 3C NMR (Bruker Avance 400) methods. Studied oxidation of propylene glycol in the presence of methanol describes by total reaction CH3CHOHCH2OH +O2 + СН3OH = CH3CHOHCOOСН3 +2H2O At first, hydroxyacetone is formed that is further oxidized to pyruvic aldehyde, which attaches alcohol to form hemiacetal. Then, hemiacetal of methyl glyoxal rearranges into methyl lactate by Cannizzaro. At 220 0C and load on a catalyst of < 2 mmol PG/gcat/h, the selectivity towards methyl lactate reaches 70 wt.% at 100 % propylene glycol conversion. The main by-products are formed as the result of acetaldehyde transformation. Acetaldehyde could be formed at hydroxyacetone aldol decondensation. In the presence of ethanol, the formation of a significant amount of acetaldehyde and its aldol condensation products as well as the formation of diethoxyethane are observed. Therefore, ethyl lactate selectivity at 100 % propylene glycol conversion does not exceed 45 %. Supported CeO2/SiO2 contact was tested in this oxidation reaction also. However, CeO2/SiO2 provides the low, up to 25%, selectivity towards methyl lactate at full propylene glycol conversion. It was shown that at the same conditions methyl lactate is formed with higher selectivity then ethyl lactate. The high methyl lactate yield up to 70 wt.% could be obtained via vapor-phase oxidation of 20% mixture of propylene glycol with methanol by air oxygen on supported CeO2/Al2O3 catalyst at 210 - 220°С and at time contact of 3-4 seconds.

The gas-phase oxidation of ethylene glycol and methanol mixture into methyl glycolate С2H6O2+CH3OH+O2 = C3H6O3+2H2О over synthesized copper-containing catalysts was studied. Methyl glycolate can be considered as raw material for obtaining biodegradable polyglycolide. The CuO-containing samples were synthesized by impregnation of granular oxide-supports (γ-Al2O3, SiO2 and MgO-ZrO2) with the calculated amount of aqueous solution of Cu(NO3)2·3H2O followed by heat treatment at 400 °C. In such way the supported CuO-MexOy /Al2O3 (Me = Mg, Ti, Cr, Co, Zn, Zr, Ag) samples have been prepared. Catalytic experiments were performed in a stainless-steel flow reactor with a fixed bed of catalyst at 200-270 °C and atmospheric pressure. Oxygen of air was used as an oxidant. The reaction products were analyzed using 13C NMR spectroscopy and gas chromatography. It was found that СuO/Al2O3 catalyst provides ~ 100% ethylene glycol conversion with 56% selectivity towards methyl glycolate at 220 °С. The main by-products are methoxymethanol, 1,1-dimethoxymethane, methyl methoxyacetate, and methyl formate. Use of silica as catalyst support leads to a significant decrease of the ethylene glycol conversion to 57 % for CuO/SiO2, but methyl glycolate selectivity does not change significantly. Promotion of СuO/Al2O3 with MgO increases methyl glycolate yield to 64%. According to the scheme of ethylene glycol sequential oxidation the increase in selectivity for methyl glycolate over CuO-MgO/Al2O3 catalyst is caused by the basic sites that promote intramolecular Cannizzaro rearrangement of the intermediate reaction product – glyoxal hemiacetal to methyl glycolate. It’s found that mixed CuO-CrO3 oxide supported by γ-Al2O3 provides 80 % methyl glycolate selectivity with 95-100% ethylene glycol conversion at 200-210 °C.