Some Aspects of the Reaction of Methyl 4,6-O-benzylidene-α-D-glucopyranoside 2,3-Carbonate with 1-Dodecanol: Novel Non-Ionic Surfactants

Abstract

The reaction of methyl 4, 6-0-benzylidene-α-D-glucopyranoside 2, 3-cyclic carbonate (2) with 1-dodecanol in the presence of a catalytic amount of triethylamine to yield the 2-O-and the 3-O-alkoxycarbonyl esters 5 and 6 is described. Catalytic hydrogenation of 5 and 6 gave the deprotected mono-esters 3 and 4 which are of interest as potential non-ionic surfactants. The corresponding ethoxycarbonyl esters 7 and 8 were also prepared and their possible role as intermediates in the formation of 2 is discussed.     

Syntheses of P-Nitrophenyl 6-O-α- and 6-O-β-D-Xylopyranosyl-β-D-glucopyranoside

Condensation of p-nitrophenyl 2,3,4-tri-O-benzoyl-β-D-glucopyranoside 3 with 2,3,4-tri-O-(chlorosulfonyl)-β-D-xylopyranosyl chloride by the Koenigs-Knorr method afforded the α-linked product in a high yield. Dechlorosulfation with sodium iodide and debenzoylation by the Zemplen method gave crystalline p-nitrophenyl 6-O-(α-D-xylopyranosyl)-β-D-glucopyranoside 7.

Compound 3 was condensed with 2,3,4-tri-O-benzoyl-α-D-xylopyranosyl bromide in the presence of mercury (II) cyanide in acetonitrile, and after debenzoylation, crystalline p-nitrophenyl 6-O-(β-D-xylopyranosyl)-β-D-glucopyranoside 10 was obtained.     

Synthesis of 2,3-UNSATURATED 4-Amino Sugars and Cyclohexyl 2,3-Di-O-Acetyl-4,6-Di-O-Methyl-α-D-Manno-Pyranoside from Cyclohexyl 4,6-Di-O-Acetyl-2,3-Dideoxy-α-D-erythro-Hex-2-Enopyranoside

ABSTRACT

The synthesis of three 2,3-unsaturated 4-amino sugars 2-4 and cyclohexyl 2,3-di-O-acetyl-4,6-di-O-methyl-α-D-mannopyranoside 8 starting from cyclohexyl 4,6-di-O-acetyl-2,3-dideoxy-α-D-erythro-hex-2-enopyranoside 1 is described. The amino sugars were prepared by allylic substitution using a palladium catalyst.     

Oxidation of L-sorbose and 2,3;4,6-di-O-isopropylidene-α-L-sorbose over supported platinum and palladium catalysts

Oxidation of L-sorbose and 2,3;4,6-di-O-isopropylidene--L-sorbose by oxygen (air) has been studied over supported Pt and Pd catalysts. The results indicate that the activity and stability of these catalysts are greatly dependent on their composition and preparation conditions.

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L- 2,3;4,6--O---L- () . , .

     

Synthesis and protonation of 2,3′-biquinolyl dianions

It has been shown that the reaction of 2, 3-biquinolyls with an excess of lithium in tetrahydrofuran leads to the formation of dianions, treatment of which with water or D₂O gives 1, 4-dihydro-2, 3-biquinolyls or their 4-D derivatives in good yield. Oxidation of the latter leads to 4-D-2,3-biquinolyl. The reduction of 2, 3-biquinolyl has been studied.Stavropol State University, Stavropol 355009. Rostov State University, Rostov-on-Don 344090. Russian University of Chemical Technology, Moscow 125190. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1391–1394, October, 1996. Original article submitted September 10, 1996.     

α-Nitro carbonyl compounds in the synthesis of 2,3-dihydrofurans

A new method for the synthesis of 2,3-dihydrofurans from readily available starting enones and α-nitro carbonyl compounds has been developed. This protocol can provide a novel and effective methodology for the preparation of 2,3-dihydrofurans in a stereoselective fashion. With 1,4-dien-3-ones, 2,3-dihydrofurans and cyclohexenecarboxylates were produced and high chemoselectivity was observed in different solvents.     

Synthesis of Methyl 2-O-, 3-O-, 4-O-, 6-O-, 2,3-Di-O- and 4,6-Di-O-β-D-Galactopyranosyl-β-D-glucopyranoside

Abstract

Synthesis of methyl O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranoside 1, methyl O-β-D-galactopyranosyl-(1→3)-β-D-glucopyranoside 2, methyl O-β-D-galactopyranosyl-(1→4)-β-D-glucopyranoside 3, methyl O-β-D-galactopyranosyl-(1→6)-β-D-glucopyranoside 4, methyl O-β-D-galactopyranosyl-(1→4)-[O-β-D-galactopyranosyl-(1→6)]-β-D-glucopyranoside 5, and methyl O-β-D-galactopyranosyl-(1→2)-[O-β-D-galactopyranosyl-(1→3)]-β-D-glucopyranoside 6, using 2,3,4,6 tetra-O-acetyl-α-D-galactopyranosyl trichloroacetimidate or 2,3,4,6 tetra-O-acetyl-α-D-galactopyranosyl bromide as a glycosyl donor and selectively protected derivatives of methyl O-β-D-glucopyranoside as glycosyl acceptors are described.     

Diffusion of monoalkyl ethers of poly(ethylene glycols) and octyl-β-D-glucopyranoside in micellar solutions

Diffusion coefficients of monoalkyl ethers of poly(ethylene glycols), С₈Е₄ and С₁₂Е₅, and octyl-β-D-glucopyranoside have been measured in aqueous micellar solutions within wide ranges of temperatures and concentrations by dynamic light scattering. The study of the С₁₂Е₅–water system containing cylindrical micelles has been supplemented with viscosity measurements, which make it possible to better monitor structural transformations and phase transformations.     

Synthesis and Structural Characterization of 2,3-Bis（hydroxymethyl）-2,3-dinitro-1,4-butanediol

2,3-Bis(hydroxymethyl)-2,3-dinitro-1,4-butanediol(C6H12N2O8) was synthesized by condensation,cyclization,oxidative dimerization and deketalization of nitromethane with a total yield of 42.4%.The structure of the title compound was characterized by 1H NMR,13C NMR,FT-IR,elementary analysis,and X-ray single-crystal diffraction analysis,which reveals that the title compound crystallizes in triclinic,space group P with a = 0.6324(2),b = 0.6454(3),c = 0.7062(3) nm,α= 111.550(4),β= 95.505(4),γ= 113.395(4)°,V = 0.23595(16) nm3,Z = 1,Mr = 240.18,Dc = 1.690 g·cm-3,μ = 0.159 mm-1,F(000) = 126,R = 0.0304 and wR = 0.0907.     

α-Aminoxylation of Ketones and β-Chloro-α-aminoxylation of Enones with TEMPO and Chlorocatecholborane

Oxidation of various cyclic and acyclic ketones under mild conditions with chlorocatecholborane, a bulky pyridine base, and TEMPO to the corresponding α-aminoxylated products in good to excellent yields (52-99%) is described. For enones as substrates, products of a β-chloro-α-aminoxylation are obtained (70-89%).     

Synthesis and Structure of 2,3-Tetra-Methylene-5,6-Trimethylene-4-Pyrone

Weattemptedtosynthesizecompound(I)bythtereactionofadipylchloridewithcyclohexanonepiperidineenamineI'1-However,weobtainedinsteadthederivativeofa4-pyrone(U)whichmaybepossiblyapotentialmedicinef[2.3]EXPERIMENTALToastirredaolutioncontainingcyclohexanonepiperidineenamine,triethylamine'andchloroform,adipy1chloridedissolvedinchloroformwasaddeddropwiseatroomtemperature.Themixturewasrefluxedfor1h,cooledandhydrolyzedwithhydrochloricacidforanother1h.Theorganiclayerwasseparated,wasbedwithwater,drie…     

Studies in the area of 2,3′-biquinolyl. 1. Arylation and hetarylation of 2,3′-biquinolyl dianion

The 2,3-biquinolyl dianion, when reacting with aryl- and hetaryl halides, forms arylation products at the 4 position, and treatment of these products with alkyl halides or water yields 1-alkyl-4-aryl-1,4-dihydro-2,3-biquinolyls or 4-aryl-1,4-dihydro-2,3-biquinolyls, respectively. Oxidation of the latter yields 4-aryl-2,3-biquinolyls. The cation dependence of the arylation reaction is demonstrated.Stavropol' State University, Stavropol' 355009. Russian Chemical Engineering University, Moscow 125190. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1094–1099, August, 1997.     

Thermolysis and [3+2]‐Cycloaddition Reactions of 2,3‐Diferrocenyl‐ and 2,3,‐Diruthenocenylcyclopropenones

Abstract

2,3‐Diferrocenyl‐ and 2,3‐diruthenocenylcyclopropenone undergo thermolysis at ～180°C with opening of the small ring via ketenocarbenes. Intramolecular transformation of the latter occurs with elimination of CO to yield dimetallocenylacetylenes. Alternatively, they enter into 1,3‐dipolar cycloaddition reactions with C≡C or C?C multiple bonds to give cyclopentadienone or cyclopentenone derivatives, respectively.     

Improved One-pot Synthesis of 4,6-Dihydroxyisophthalic Acid and 2,3-Dihydroxyterephthalic Acid

An improved method for the large-scale preparation of 4,6-dihydroxyisophthalic acid and 2,3-dihydroxyterephthalic acid has been developed.Compared to the previous procedures,this new process-requires much lower CO2 pressure of 0.3 Mpa and shorter reaction time.thus providing a convenient access for large-scale synthesis.The yield is high （93% and 65%,respectively）, and the oxidation of phenol is nearly inhibited,neither decolorization nor further chromatographic purification is required.     

Thermal degradation of bromine-containing polymers. Part 9—Copolymers of 2,3-dibromopropyl methacrylate and 2,3-dibromopropyl acrylate with styrene

The products of the thermal degradation of copolymers of styrene (S) with 2,3-dibromopropyl methacrylate (2,3-DBPM) and 2,3-dibromopropyl acrylate (2,3-DBPA) have been analysed quantitatively using thermal analysis, infra-red spectroscopy, mass spectrometry and gas-liquid chromatography. The products are generally similar to those which result from the degradation of the two homopolymers and no significant interaction occurs between the two types of units in the polymer chains. The only abnormal feature is the fact that the yield of 2,3-DBPA increases as the 2,3-DBPA content of copolymers of 2,3-DBPA and S decreases but this is consistent with previous observations in related copolymer systems.     

Isolation and Immobilization of Influenza Virus-Specific N-SA-α-2,3-Gal Receptors Using Magnetic Nanoparticles Coated with Chitosan and Maackia amurensis Lectin

Avian influenza viruses preferentially bind to sialic acid alpha-2,3-galactose (N-SA-α-2,3-Gal) receptors on epithelial cells. Herein, we describe a procedure we have developed for isolation of N-SA-α-2,3-Gal receptors from porcine trachea using magnetic nanoparticles (NPs) coated with chitosan (NP-Ch) and functionalized with Maackia amurensis lectin (NP-lectin). Magnetic nanoparticles were coated with chitosan in a one-step co-precipitation, and then M. amurensis lectin was immobilized covalently using glutaraldehyde. Lectin coated nanoparticles were incubated with sialic acid enriched fraction of tracheal homogenate, and N-SA-α-2,3-Gal receptor was extracted under magnetic field in two cycles. The presence of 66.4 kDa protein was determined by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The interaction of immobilized receptor (NP-Ch-R) with M. amurensis lectin (NP-Ch-R-L) was demonstrated by Fourier transform infrared spectrometry (FTIR) and thermogravimetric analysis (TGA).     

New insights into the transitional behaviour of methyl-6-O-(n-dodecanoyl)-α-D-glucopyranoside using variable temperature FTIR spectroscopy and X-ray diffraction

The liquid crystalline behaviour of methyl-6-O-(n-dodecanoyl)-α-D-glucopyranoside, 1, has been characterised using X-ray diffraction and variable temperature Fourier transform infrared (FTIR spectroscopy). 1 exhibits a monotropic interdigitated smectic A phase consisting of bilayers in which the alkyl chains are overlapped. The crystal–isotropic transition is accompanied by a pronounced decrease in the strength of the hydrogen bonding network involving the sugar groups resulting in a marked change in the environment of the alkyl chains. The isotropic phase consists of disordered smectic-like domains stabilised via hydrogen bonding between the sugar groups. At the transition to the smectic A phase, a subtle change in hydrogen bonding is observed which is manifested by a change in the temperature dependence of the OH stretching peak position in the FTIR spectrum. On crystallisation, the strong hydrogen bonding network is re-established accompanied by a change in the conformational distribution of the alkyl chains. A model is proposed in which a combination of hydrogen bonding (enthalpic effects) and conformational arrangements (entropic effects) promotes initially the formation of smectic-like domains in the isotropic phase and subsequently stabilises the smectic A phase by inhibiting the microphase separation leading to the crystal phase.     

Synthesis of 17α-bromovinyl- and 17α-iodovinylnortestosterone derivatives

Depending upon the reaction conditions, norethisterone (1) and its ketal 2 can be transformed with tributyltin hydride to either the (E)-or(Z)-17α-(2-tributylstannylvinyl)-nortestosterone derivatives 3, 8 and 13. Further treatment with N-bromo- or N-iodosuccinimide yields the corresponding (E)- and (Z)-17α-halovinyl steroids 6,7,10 and 11. Radio-labelled (Z)-17α-(2-iodovinyl)-nortestosterone was prepared by reaction of the 17α-stannylvinyl derivative 13 with Na¹²⁵I.