Insect pheromones and their analogs. LX. Stereocontrolled synthesis of sex pheromones ofDrosophila mulleri andMayetiola destructor

Syntheses are developed for 2S-tridecyl- and 2S-tridec-10E-enylacetates, sex pheromones of the fruit flyDrosophila mulleri and the Hessian flyMayetiola destructor, respectively, that are based on ethyl-3S-hydroxybutanoate, a product from enzymatic reduction of ethyl acetoacetate by the soil yeast strain 80-1.Work performed under the auspices of the Federal program Integratsiya of the RF (Contract No. A 0005).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 167–169, March–April, 2000.     

Composition,structure, and catalytic activity of Ni- and Cu-containing plasma-electrolytic coatings on titanium

Unmodified and modified nickel- and copper-containing oxide layers were formed on a titanium support and their composition, structure, and catalytic activity in a model reaction of CO oxidation were studied.     

Microwave enhancement of arylation of activated olefins with 4-bromoacetophenone

Russian Journal of Organic Chemistry -     

Conformational,optical, electro-optical,and dynamic characteristics of cross-linked poly(N-acryloyl-11-aminoundecanoic acid)

Polymerizable surfactants now attract a great interest due to high potential of their practical application as components of pseudostationary phase in micellar chromatography, drug carriers, and “building blocks” for molecular design of nanoparticles and nanostructured polymer materials, for encapsulation of various biological preparations. In the present work, we have studied poly(N-acryloyl-11-aminoundecanoic acid) (cross-linked comb-like polymer). Cross-linked polymers were obtained via copolymerization of the surfactant bearing double bond in hydrophobic tail with hydrophobic bifunctional cross-linker in micellar solution. Of special interest was the comparison between cross-linked and non-cross-linked polymers and influence of alkaline medium on characteristics of these samples. Non-cross-linked polymers were obtained by hydrolysis of the cross-linked product (treating with NaOH). The mixture of cyclohexanol and dioxane (1:1 volume ratio) was used as a solvent. Detailed studies of the obtained polymers by viscometry, dynamic light scattering, flow birefringence, and equilibrium and non-equilibrium electric birefringence were performed. It was established that during cross-linking process, two types of bonds are formed (the ones inside individual molecules and between several polymer chains). It was shown that cross-linked macromolecular nanoparticles can be transformed into comb-like polymers.     

Optical, dynamic, and electro-optical properties of poly(N-acryloyl-11-aminoundecanoic acid) in solutions

The optical, electro-optical, and dynamic characteristics of poly(N-acryloyl-11-aminoundecanoic acid) in organic solvents and of the sodium salt of its monomer in water were studied via the methods of flow birefringence, equilibrium and nonequilibrium electric birefringence, and dynamic light scattering. It is shown that, in aqueous solutions, the monomer forms coarse particles of both symmetric and asymmetric shapes. The linear dimensions of these particles are estimated from the data of translational and rotational diffusion. Polymer macromolecules in organic solvents feature negative anisotropy of optical polarizability. Contributions of optical microform and macroform effects to the observed flow birefringence are analyzed in detail. The intrinsic optical anisotropy of the monomer unit of the polymer, which correlates well with the corresponding values for comb-shaped polymers of a similar structure, is estimated. It is shown that polymer molecules lack marked intrinsic permanent macromolecular dipoles and that electric birefringence in their solutions is associated with macroscopic induced dipole moments that appear during orientation of the dipole moments of polar groups in side chains of the polymer under application of an electric field.     

Structure and properties of boundary layers of water

Conclusions In experiments performed by various methods and on different objects, it has been shown that the properties of water in boundary layers and in fine pores are substantially different from the bulk properties. These differences play an important role in various technological processes. For example, the stability of thin films of water often determines flotation conditions and the mass transfer in drying porous solids. The presence of boundary layers of water with changed properties increases the stability of a number of colloidal systems, and this must be taken into account in developing measures for water treatment to remove suspended matter. Finally, the special properties of boundary layers of water, in particular their lower dissolving power, are finding broad practical applications in the technology of reverse osmosis separation of solution and in water desalination.All of this creates a need for further research on the special properties of thin layers of water and aqueous solutions and a need for the development of the theory of boundary structures, with the aim of controlling the property of the boundary layers in the directions that are needed for practical purposes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1698–1710, August, 1982.     

Melissa officinalis L. Aqueous Extract Exerts Antioxidant and Antiangiogenic Effects and Improves Physiological Skin Parameters

Melissa officinalis (MO) is a medicinal plant well-known for its multiple pharmacological effects, including anti-inflammatory, anticancer and beneficial effects on skin recovery. In this context, the present study was aimed to investigate the in vitro and in vivo safety profile of an MO aqueous extract by assessing cell viability on normal (HaCaT—human keratinocytes) and tumor (A375—human melanoma) cells and its impact on physiological skin parameters by a non-invasive method. In addition, the antioxidant activity and the antiangiogenic potential of the extract were verified. A selective cytotoxic effect was noted in A375 cells, while no toxicity was noticed in healthy cells. The MO aqueous extract safety profile after topical application was investigated on SKH-1 mice, and an enhanced skin hydration and decreased erythema and transepidermal water loss levels were observed. The in ovo CAM assay, performed to investigate the potential modulating effect on the angiogenesis process and the blood vessels impact, indicated that at concentrations of 100 and 500 µg/mL, MO aqueous extract induced a reduction of thin capillaries. No signs of vascular toxicity were recorded at concentrations as high as 1000 μg/mL. The aqueous extract of MO leaves can be considered a promising candidate for skin disorders with impaired physiological skin parameters.