Structure of 2-chloro-3-phenylbenzoic acid

The carbonylation reaction of 2,3-dichlorobiphenyl proceeds with a substitution of the chlorine atom in position 3 and results in the formation of 2-chloro-3-phenylbenzoic acid. The structure of this acid is revealed by single crystal XRD. It is determined by steric interactions of substituents in positions 2,4,2′, and 6′, a stable carboxyl supramolecular synthon, and weak interactions with the participation of the carbonyl oxygen atom and the chlorine atom. Original Russian Text Copyright ? 2009 by V. P. Boyarskiy, M. S. Fonari, K. Suwinska, and Yu. A. Simonov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 3, pp. 605–607, May–June, 2009.     

Some symmetry aspects of layered-clathrate structures formed by Ni (NCS)2 (4-methylpuridine)4

The crystal structures of layered clathrate inclusion compounds of Ni(CNS)₂ (4-methylpyridine)₄ with 1-bromonaphthalene (I) and azulene (II) were analyzed by x-ray single-crystal diffractometry [crystal data: I–C₄₆H₄₂N₆S₂Br₂Ni; a=11.88(1), b=11.82(1), c=32.79(3), =102.0(1), Z=4, P2₁/c; II–C₄₆H₄₄N₆S₂Ni; a=11.51(2), b=11.64(1), c=32.98(2), =103.4, Z=4, P2₁/n]. Disordering of guest molecules in I is concluded, based on x-ray study, and positions of the guest (each of the two symmetry independent molecules disordered over two orientations) have been refined. In II disoder of guest-azulene is also observed but only one from the two symmetrically independent guest molecules could be located from the x-ray data. The empirical force field calculations were performed for I and II. The results were used for location of the second azulene molecule and for discussion of the disorder mole (short or long-range).     

On the clathratogenic properties of the Ni (NCS)2 (4-Vinylpyridine)4 host

The crystal structure of the non-clathrated -Ni(NCS)₂ (4-Vinylpyridine)₄ complex was solved and refined to R=0.056 (crystal data: a=11.27(3), b=16.86(1), c=32.06(1) Z=8, V=6092 ų;Pbca; d_x=1.30 g. cm^–3). The complex molecule adopts an asymmetric, windmill conformation of the four pyridine ligands. The -phase was used as a solid substrate for clathration of liquid o-, m- and p-xylene, at 25°C. The composition of the products, the enthalpies of clathration and kinetic course of the processes were investigated. The clathration enthalpies, per mole of the host, are equal to 17.07, 14.1 and 21.77 kJ and correspond to the 1.05, 1.11 and 1.30 guest/host molar ratios for, respectively, ortho, meta and para-xylene. The clathration rates follow the order para>ortho>meta. The results are discussed from the structural point of view.     

The role of template in the synthesis of meso-hexamethyl-meso-hexaphenyl-calix[6]pyrrole: trihalogenated compounds as templates for the assembly of a host with a trigonal cavity

Trihalogenated compounds act as effective and selective templates in the template-assisted synthesis of meso-hexaphenyl-calix[6]pyrrole.     

IntelliDrug Implant for Medicine Delivery in Alzheimer's Disease Treatment

Summary : IntelliDrug it is a denture implant containing a reservoir with drug and making enable a galantamine transport via buccal mucosa by means of iontophoresis. The in vitro experimental studies on drug passive and iontophoretic transport through porcine buccal mucosa were carrying out in horizontal two-chamber permeation cell with silver electrodes. The drug mass flux was investigated. The influences of initial drug concentration and current density for transport velocity were defined.     

Antimicrobial Activities Evaluation and Phytochemical Screening of Some Selected Plant Materials Used in Traditional Medicine

Plant extracts are a source of valuable ingredients that can be used in many industries. This paper presents research on the content of selected bioactive compounds in extracts obtained from various plant materials. Raw materials have a documented use in traditional medicine not only in Poland. The tested plants were: bitter melon (fruit), elderberry (flowers, fruit, leaves), wild rose (fruit, flesh, seeds), mountain ash (fruit), guelder rose (fruit), and sea buckthorn (fruit, leaves, pomace). The main goal of these tests is to indicate the potential raw materials that may constitute an alternative source of bioactive compounds with antimicrobial activity. The plant material was tested for the content of bioactive antioxidant compounds and possible antimicrobial activity. The content of polyphenols (phenolic acids and flavonoids) was analyzed using UPLC/PDA, sterols, organic acids, and other bioactive compounds. The minimum inhibitory concentration (MIC) was determined. The total free phenolic acids (TPC) and total free flavonoids (TFC) of all plant raw materials was varied and ranged from 0.21 (mg RUTE/1 g of extract) to 38.30 mg RUTE/1 g of extract) for TFC. The concentration of sterols was, on average, about 10 mg/1 g of extract. The value of approx. 20 mg/1 g of the extract was recorded for bitter melon and beach rose. The content of organic acids was about 1.5 mg/1 g of the extract to even 13 mg/1 g of the extract for sea buckthorn berries. The most sensitive to the extracts’ activity were the following bacteria: M. luteus, P. mirabilis, P. fragii, S. enteritidis, and E. coli. The tested plant materials can be used in various industries as a source of bioactive compounds of an antibacterial nature.     

High-pressure crystallization of isotactic polypropylene droplets

Dispersions of isotactic polypropylene (PP) particles in polystyrene (PS) were produced by interfacially driven breakup of nanolayers in multilayered systems that were fabricated by means of layer-multiplying coextrusion. The droplet size was controlled by the individual PP layer thickness ranging from 12 to 200?nm. In addition, PP was melt blended with PS to produce PP droplets larger than those formed by breakup of nanolayers. The dispersions of PP particles in the PS matrix were melted and annealed under high pressure of 200?MPa. Only the largest PP droplets, with average sizes of 170?μm, crystallized predominantly in the γ form. In the 42-μm droplets obtained by breakup of 200?nm layers, a minor content of the γ form was found whereas the smaller droplets obtained by breakup of the thinner nanolayers contained the α form and/or the mesophase. The results showed that the γ phase formed only in the droplets sufficiently large to contain the most active heterogeneities nucleating PP crystallization under atmospheric pressure. It is concluded that the presence of nucleating heterogeneities is necessary for crystallization of PP in the γ form under high pressure.     

ESI–MS method for in vitro investigation of skin penetration by copper–amino acid complexes: from an emulsion through a model membrane

Copper can be found in many cosmetic formulations, mainly as complexes with peptides, hydroxyacids or amino acids. The main reason that the usage of this element in this context is still increasing is its beneficial biochemical activity, although the mechanism that enables its complexes to permeate through skin barriers is largely unknown. The ability of copper complexes with amino acids to penetrate through the stratum corneum and participate in copper ion transport processes is key to their cosmetic and pharmaceutical activities. The penetration process was studied in vitro in a model system, a Franz diffusion cell with a liposome membrane, where a liquid crystalline system with physicochemical properties similar to those of the intercellular cement of stratum corneum was used to model the skin barrier. The influences of various ligands on the model membrane migration rate of copper ions was studied, and the results highlighted the crucial roles of metal ion complex structure and stability in this process.     

Upper rim substituted thiacalix[4]arenes

The synthesis and structure of new tetrahydroxythiacalix[4]arenes, existing in the cone conformation and possessing reactive bromide, chloromethyl or diorganylphosphoryl groups on the upper rim of the macrocycle are described. The molecular structure of tetrakis(diisopropoxyphosphorylmethyl)thiacalix[4]arene was examined by X-ray crystallography.