Chemical Modification of Peat Humic Acids To Increase Their Bioactivity

The possibility of chemical modification of peat humic acids in order to increase their bioactivity by reduction with tin(II) chloride and sodium borohydride and also by carboxylation using the Kolbe method was analyzed.     

Reaction of H2PtCl6 with 18-crown-6 and dibenzo-18-crown-6 in 1,2-dichloroethane and acetonitrile

Compounds of the compositions [2(18-crown-6)6(H₂O)2(C₂H₄Cl₂){Pt²⁺(C₂H₄)}(Pt₂Cl₁₀)^2–], [4(18-crown-6)2(OH₃)⁺2(OH₂)2(NH₃)(Pt₂Cl₁₀)^2–], [(dibenzo-18-crown-6)6(H₂O){Pt²⁺(C₂H₄)}(Pt₂Cl₁₀)^2–], and [4(dibenzo-18-crown-6)2(OH₃)⁺2(OH₂)2(NH₃)Pt₂Cl₁₀)^2–] were prepared by reactions of H₂PtCl₆ with 18-crown-6 and dibenzo-18-crown-6.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 10, 2004, pp. 1593–1599.Original Russian Text Copyright © 2004 by Guseva, Busygina, Khasanshin, Polovnyak, Yarkova, Yusupov.This revised version was published online in April 2005 with a corrected cover date.     

Reaction of dibenzylphosphinous acid with formic acid esters

Summary The reaction of dibenzylphosphinous acid with formic acid esters was studied in the presence of sodium. Here we obtained dibenzylmethylolphosphine oxide and the enol form of the phenylalkoxybenzylphosphorylacetaldehyde.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 6, pp. 1085–1088, June, 1965     

Synthesis and mesomorphic properties of esters derived from alkanediols

New alkane-α,ω-diyl esters, propane-1,3-diyl and butane-1,4-diyl bis[4-(4-alkoxybenzoyloxy)-3-bromobenzoates], were synthesized and were found to form nematic mesophase. The effects of the lateral substituent and the length of the central and terminal hydrocarbon chains on the mesomorphic properties of butane-1,4-diyl bis[4-(4-alkoxybenzoyloxy)-3-bromobenzoates] were studied. Structural factors responsible for mesogenic properties of these compounds were determined by conformation analysis.     

Complex Formation of Potassium Hexachloroplatinate with 18-Crown-6 and Dibenzo-18-Crown-6 in Acetonitrile

The products of the reactions between potassium hexachloroplatinate {K₂PtCl₆} and 18-crown-6 or dibenzo-18-crown-6 in acetonitrile were studied. Pure crystalline compounds [2K·2(18-crown-6)· 2CH₃CN]²⁺·[PtCl₆]^2-·2H₂O, [2K·dibenzo-18-crown-6·CH₃CN]^{2 +}·[PtCl₆]^{2 -}, and [2K·dibenzo-18-crown-6·CH₃CN]^{2 +}·[Pt₂Cl₁₀]^{2 -} were obtained. Physicochemical properties of these compounds were studied, and their near- and far-IR IR spectra and thermogravimetric curves were considered. The composition of the complexes is determined by metal:ligand molar ratio and crown ether nature. It was found that acetonitrile is coordinated via the nitrogen atom.     

Characteristic features of atomization processes and their effect on the shape of Arrhenius curves in electrothermal atomic-absorption spectrometry

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 2, pp. 183–190, August, 1990.     

Synthesis and mesomorphism of 1,3-benzenedicarboxylic acid derivatives

4-Methoxy-l,3-benzenedicarboxylic acid esters and 4-(4-hexyloxybenzoylamino)phenyl 1,3-benzenedicarboxylate, each containing five aromatic rings, were synthesized. The influence of the structure of the synthesized banana-like compounds on their mesogenic activity was examined.