The Comparison of the Orientation of Sodium 3-Hydroxy-2-Naphthalenecarboxylate in the Cavity of β-Cyclodextrin and Heptakis-(2,3,6-Tri-O-Methyl)-β-Cyclodextrin

Conformational analysis of inclusion complexes of sodium 3-hydroxy-2-naphthalenecarboxylate with k080n5454487v2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin and heptakis-(2,3,6-tri-o-methyl)-k080n5454487v2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin in D₂O was investigated by 1D and 2D ¹HNMR measurements. The results show that part of the naphthyl group of sodium 3-hydroxy-2-naphthalenecarboxylate is situated in the 2,3-OH side of the k080n5454487v2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin cavity asymmetrically while the whole naphthyl group is included in the heptakis-(2,3,6-tri-o-methyl)-k080n5454487v2/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-cyclodextrin cavity with the caboxylate and hydroxy group close to the 6-OCH₃ group.     

C→N Migrations of the ethoxycarbonyl group in reactions of ortho-substituted aryl isocyanates with the 1,3-zwitterion derived from triisopropylphosphine and ethyl 2-cyanoacrylate

The reactions of meta—para-substituted aryl isocyanates with phosphorus-containing 1,3-zwitterions, which proceed with the Ck061836177314108/xxlarge8594.gif" alt="rarr" align="BASELINE" BORDER="0">N migration of the CO₂Et group to form the corresponding carbamates, were extended to ortho-substituted aryl isocyanates. The influence of the steric and electronic effects of the ortho substituents in the aromatic rings of aryl isocyanates on the ease of this rearrangement is qualitatively considered.     

Mixed strategy solutions forN-person quadratic games

Mixed strategy k/xxlarge8712.gif" alt="isin" align="MIDDLE" BORDER="0">-equilibrium points are given forN-person games with cost functions consisting of quadratic, bilinear, and linear terms and strategy spaces consisting of closed balls in Hilbert spaces. The results are applied to linear-quadratic differential games with no information and quadratic integral constraints on the control functions.This work was supported by a Commonwealth of Australia, Postgraduate Research Award.     

Transformed steroids

A preparative method for 9a-hydroxylation of k51191/xxlarge916.gif" alt="Delta" align="BASELINE" BORDER="0">⁵-3k51191/xxlarge946.gif" alt="beta" align="MIDDLE" BORDER="0">-hydroxysteroids using the fungi ofCircinella sp. 10Kh-1220 not capable of modifying theA ring has been developed. It is established that the yields of the main and the side products greatly depend on the transformation conditions, mycelium age, and the structure of the steroid substrate. Under the optimal transformation conditions novel 9k51191/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-hydroxysubstituted derivatives of androstenolone, pregnenolone, 16-dehydro-16k51191/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">,17k51191/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-epoxy-, and-16k51191/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-methoxypregnenolone have been obtained in 36–80 % yields.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 737–743, April, 1994.     

2,6-Di-tert-butylphenols and phenoxyl radicals with metal—metal bonds

k0m10183r3350v12/xxlarge963.gif" alt="sgr" align="BASELINE" BORDER="0">-Aryl trans-bistriphenylphosphine complexes based on 2,6-di-tert-butylphenol containing Pt—SnCl₃, Pt—GeCl₃ groups were synthesized. Oxidation of these compounds gives the corresponding phenoxyl radicals, which were studied by ESR spectroscopy. The transformation of the diamagnetic complexes to the paramagnetic state is accompanied by cleavage of the Pt—Sn, Pt—Ge bonds and by elimination of SnCl₂, GeCl₂.     

Eco-dyeing and functional finishing of wool fabric based on Portulaca oleracea L. as colorant and Musa basjoo as natural mordant

Biomass energy is the most acknowledged renewable resource due to its universality, richness, and renewability. This study utilized a Portulaca oleracea L. plant as a natural colorant for wool fabric dyeing with a high color yield at optimum extraction and dyeing conditions. To evaluate the dyeing mechanism and feasibility of the extracted dyes, we analyzed and characterized the molecular structure and nano-level particle size. The dyeing kinetics and the morphology of dyed fabrics were integratedly explored; the adsorption process of wool fabric on natural colorant molecules was increasingly in line with the pseudo-second-order kinetic adsorption model. Further, the dyeing effects of wool fabrics were compared to that of Musa basjoo mordant and synthetic dyes to confirm the superior color depth (K/S value 23.53), biological function as anti-ultraviolet (UPF value 253.47), and anti-bacterial activity (antibacterial rate of Staphylococcus aureus/Escherichia coli was 71.3%/37%). Our findings provide a feasible scheme for providing deep color and biological activity to wool fabrics. This has broad application prospects in the field of eco-friendly textile materials.     

2-Methylthio-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-<Emphasis Type="Italic">a</Emphasis>]pyrimidin-5- and -7-Ones

The cyclocondensation of methylcinnamates and arylidene derivatives of Meldrumk7x/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">s acid with 3-amino-5-methylthio-1,2,4-triazole in DMF gives 2-methylthio-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]-pyrimidin-5-ones. The reaction involving arylidene derivatives of Meldrumk7x/xxlarge8217.gif" alt="rsquo" align="BASELINE" BORDER="0">s acid or its synthetic equivalents in ethyl acetate with a catalytic amount of pyridine gives a mixture of 2-methylthio-4,5,6,7-tetrahydro-1,2,4-triazolo[1,5-a]pyrimidin-5- and -7-ones.__________Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 246–251, February, 2005.     

Conformational studies of basic poly (α-amino acid)s in reversed micelles

The conformation of various basic poly (k20j60v5/xxlarge945.gif" alt="agr" align="BASELINE" BORDER="0">-amino acid)s was investigated by CD measurements in aqueous solutions containing bis (2-ethylhexyl)sodium sulfosuccinate (AOT) as well as in the AOT reversed micelles. The addition of AOT into an aqueous solution of poly(L-lysine) induces the conformational transition from coil to ordered structure, followed by aggregation. On the other hand, poly(L-lysine) assumesk20j60v5/xxlarge914.gif" alt="Bgr" align="BASELINE" BORDER="0">-structure in the reversed micelles at low w_ovalue (w_o=[H₂O]/[AOT]). Similarly to poly(L-lysine), poly(L-ornithine) takes an ordered structure in the aqueous solution containing AOT andk20j60v5/xxlarge914.gif" alt="Bgr" align="BASELINE" BORDER="0">-structure in the reversed micelles. In this case, however, these ordered structures are not so stable, compared with that of poly(L-lysine). Poly(L-arginine) undergoes the conformational transition from coil to helix by addition of AOT into the aqueous solution. Further addition of AOT allows transformation intok20j60v5/xxlarge914.gif" alt="Bgr" align="BASELINE" BORDER="0">-structure. Copoly(L-lysyl-L-leucine) with 63% leucine residue was shown to take a stable helical conformation even in pure water. In the reversed micelles, however, this ordered structure is significantly changed probably because the hydrophobic interaction among the leucyl residues is lowered in the reversed micelles.     

Emission,Emissionslebensdauer und Absorption von [Cr urea6]X3-Einkristallen

Emission and absorption polarization spectra as well as emission lifetimes between room temperature and 5 °K have been measured of [Cr urea₆]X₃ single crystals, where X stands for ClO ₄ ^– , J^–, NO ₃ ^– , Br^–, Cl^–, F^–, and X₃ for JSO ₄ ^3– . The strong temperature dependence of the fluorescence/phosphorescence-ratios, and of the emission lifetimes is discussed. The differences between the spectra as well as the emission lifetimes of the various salts can be attributed to an anion dependent trigonal perturbation.kquote>kquote>Die Autoren danken dem Verband der Chemischen Industrie für finanzielle Unterstützung dieser Arbeit.