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Bridged 1,2,4,5-tetraoxanes were prepared using available acidic ion exchange resin with high yields despite the possibility of peroxide decomposition under heterogeneous conditions. The bridged tetraoxanes demonstrated high cytotoxicity against HeLa cancer cells in vitro, which in some cases was higher than that of cisplatin, artesunate, and dihydroartemisinin.

Synthetic ozonides and tetraoxanes were shown to have high cytotoxicity in vitro when tested on androgen-independent prostate cancer cell lines DU145 and PC3, which is in some cases was higher than that of doxorubicin, cisplatin, etoposide, artemisinin, and artesunate. Activity of ozonide stereoisomers differs from each other. This difference in activity and absence of correlation between activity of stereoisomers and their oxidative properties allow us to suggest existence of a quite specific mechanism of cytotoxicity of these endoperoxides different from a traditional mechanism based mainly on oxidative properties of peroxides.

A new method for the synthesis of arylthiocyanates from derivatives of aniline, pyrrole, and indole is described. Products had antimicrobial activity. Dithiocyanates N-methylpyrrole and N-phenylpyrrole were active against Candida albicans, Candida tropicalis, Candida krusei, and Aspergillus niger with activity levels comparable to those of fluconazole and amphotericin.

Cyclic peroxides as initiators for the radical polymerization of methyl methacrylate were proposed. The initial rates, initiation rates, and effective activation energies of polymerization initiated by cyclic peroxides and cyclic peroxide-1-pyridyl-2-ferrocene systems were determined. The radical yields to the volume upon the thermal decomposition of cyclic peroxides and their catalytic decomposition in the presence of 1-pyridyl-2-ferrocene were determined. In combination with 1-pyridyl-2-ferrocene cyclic peroxides form efficient initiating systems favoring an increase in the polymerization rate, a decrease in the molecular weights, and an increase in syndiotacticity of the synthesized poly(methyl methacrylate). © 2013 Springer Science+Business Media New York.

General methods are presented for the preparation of symmetric and asymmetric 1,2,4,5-tetraoxanes, based on peroxidation of carbonyl compounds and their derivatives.

Iodine-catalyzed reactions of bis(1-hydroperoxycycloalkyl) peroxides with ketals give, via replacement of two alkoxy groups, the cyclic peroxides, 1,2,4,5,7,8-hexaoxonanes, in up to 82% yields. The cyclization is very sensitive to the solvent nature. Among MeCN, Et2O, THF, CHCl3, CH2Cl2, hexane, and MeOH, the best results were achieved with the first three solvents.

A series of six new geminal bis-hydroperoxides were synthesized based on cyclic ketones. Experiments in vitro show that the synthesized compounds exhibit pronounced antimicrobial properties that are comparable with the effect of some antiseptics and, to a lesser extent, antibiotics. Tests on B. cereus, E. coli, P. aeruginosa, S. aureus, C. albicans, and A. niger showed that bis-hydroperoxides were similar to hydrogen peroxide with respect to both the spectrum of action and the MIC level (0.1, 1.0, and 10 mg/mL), which is evidence for a similar mechanism of antimicrobial action.

Electrolysis of 2-oxa- and 2,5-dioxabicyclo[n.4.0]alk-1(6)0enes (n=4, 10) under conditions of direct undivided anodic oxidation in methanol results in their electrochemical mono-and dimethoxylation; electrolysis of the corresponding 2-oxa-and 2,5-dioxabicycloalkanes involves electrochemical cleavage of the bridging carbon—carbon bonds followed by electrooxidative transformation into methyl ω-(2-methoxytetrahydrofuryl)-, ω-(dimethoxy-methyl)-, and ω-(1,3-dioxolan-2-yl)alkanoates.

A catalytic procedure has been developed for the synthesis of 15-pentadecanolide (1) from readily available 1-hydroperoxy-16-oxabicyclo[10.4.0]hexadecane (2). The method is based on the reaction of hydroperoxide2 with copper acetate (0.15–5 mol.%). Ring expansion occurred as a result of generation of tertiary bicyclohexadecyloxyl radicals4 from hydroperoxide2 under the action of Cu1 ions, β-scission of the radicals accompanied by regioselective cleavage of the bridge bond to form macrocyclic C-centered radicals5, and their oxidation by Cu11 ions to (E)-11- and (E)-12-pentadecen-15-olides (6). The products obtained were converted into 15-pentadecanolide by subsequent catalytic hydrogenation over a Pd catalyst in a yield of more than 90% with respect to hydroperoxide2.