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1992 Volume 3 Issue 6
1992, 3(6): 407-408
Abstract:
As models of 5, 10-methenyl-tetrahydrofolate coenaymes imidazolinium salts 6a, b were synthesized and their carbontransfer reactions with several types of nucleophiles were studied
As models of 5, 10-methenyl-tetrahydrofolate coenaymes imidazolinium salts 6a, b were synthesized and their carbontransfer reactions with several types of nucleophiles were studied
1992, 3(6): 409-410
Abstract:
25-Hydroxycholesterol, which is an important intermediatefor the synthesis of 25-hvdroxyvitamin D3 and 1α, 25-dihydroxyvitamin D3,was prepared efficiently from hyodeoxycholic acid in 31% overall yield inseven steps
25-Hydroxycholesterol, which is an important intermediatefor the synthesis of 25-hvdroxyvitamin D3 and 1α, 25-dihydroxyvitamin D3,was prepared efficiently from hyodeoxycholic acid in 31% overall yield inseven steps
1992, 3(6): 411-414
Abstract:
The kinetics of PTC-Wittig reaction between substitutedaromatic aldehydes and 2-butenyl methyldiphenylphosphonium salthas been studied.The low reaction constant (ρ=0.30) impliesthat these PTC-Wittig reactions take place through low polarintermediate
The kinetics of PTC-Wittig reaction between substitutedaromatic aldehydes and 2-butenyl methyldiphenylphosphonium salthas been studied.The low reaction constant (ρ=0.30) impliesthat these PTC-Wittig reactions take place through low polarintermediate
1992, 3(6): 415-416
Abstract:
In this paper, we report a new method for preparing acetylthioformanilides from substituted pyruvanilides an Lawessow Reagent.in DME at room temperature.Some new x-acetylthioanilides aresynthesized by this method
In this paper, we report a new method for preparing acetylthioformanilides from substituted pyruvanilides an Lawessow Reagent.in DME at room temperature.Some new x-acetylthioanilides aresynthesized by this method
1992, 3(6): 417-418
Abstract:
In a facile procedure, 2-(1, 3-dithian-2-ylidene)-l-arylketones 1 vere reduced with magnesium in methanol to give α-aryl-β-(1, 3-dithane) alcohols 2 in good to high yields
In a facile procedure, 2-(1, 3-dithian-2-ylidene)-l-arylketones 1 vere reduced with magnesium in methanol to give α-aryl-β-(1, 3-dithane) alcohols 2 in good to high yields
1992, 3(6): 419-420
Abstract:
An aromatization reaction was found when 18--methyl--estra--4(5),9(10)--dien--3, 17--dione(6) was treated with triethyl orthoforrnate in dioxane in thepresence of catalytic amount of p--toluenesulfonic acid (TsOH), and 18--methyl--9(11)--dehydroestrone--3--ethyl ether (8) was obtained in 70% yield.The mechanism wasfound to be a process of etherification--oxidation reaction
An aromatization reaction was found when 18--methyl--estra--4(5),9(10)--dien--3, 17--dione(6) was treated with triethyl orthoforrnate in dioxane in thepresence of catalytic amount of p--toluenesulfonic acid (TsOH), and 18--methyl--9(11)--dehydroestrone--3--ethyl ether (8) was obtained in 70% yield.The mechanism wasfound to be a process of etherification--oxidation reaction
1992, 3(6): 421-422
Abstract:
Wittig reaction in methanol was investigated, and a possiblemechanism was proposed
Wittig reaction in methanol was investigated, and a possiblemechanism was proposed
1992, 3(6): 423-424
Abstract:
Three new solid complexes of macrocyclic polyether ligand 2, 2'-dinitro-4, 5, 4', 5'bis-(15-crown-5)-dihenzo disulfide(L) with trivalent rare earth nitrates having composition of RE(NO3)3ړLړ6H2O(RE=Ce, Pr, Nd) have been synthesized in acetonitrile.All the isolated complexes have beencharacterized by elementary analysis, IR and UV spectra, differential thermal and thermogravimetricanalysis, X-ray powder diffraction analysis, molar conductance and measurements of solubility insome general solvents
Three new solid complexes of macrocyclic polyether ligand 2, 2'-dinitro-4, 5, 4', 5'bis-(15-crown-5)-dihenzo disulfide(L) with trivalent rare earth nitrates having composition of RE(NO3)3ړLړ6H2O(RE=Ce, Pr, Nd) have been synthesized in acetonitrile.All the isolated complexes have beencharacterized by elementary analysis, IR and UV spectra, differential thermal and thermogravimetricanalysis, X-ray powder diffraction analysis, molar conductance and measurements of solubility insome general solvents
1992, 3(6): 425-426
Abstract:
From the hook of Uncaria sinensis, a new alkaloid, isorhynchophyllicacid was isolated and its structure was elucidated by spectral data and chemicalreaction
From the hook of Uncaria sinensis, a new alkaloid, isorhynchophyllicacid was isolated and its structure was elucidated by spectral data and chemicalreaction
1992, 3(6): 427-430
Abstract:
Two new Components, spiramine N (1) and spiraminol (2) were isolated fromSpiraea japonica var.aecuminata Franch.Their structureswere elucidated bychemical and spectxalmeans
Two new Components, spiramine N (1) and spiraminol (2) were isolated fromSpiraea japonica var.aecuminata Franch.Their structureswere elucidated bychemical and spectxalmeans
1992, 3(6): 431-432
Abstract:
Two new minor steroidal saponins, (25R) spirostan-3β-ol-6-one-3-O-[α-L-arabinopyranosyl(1-4)]-β-D-glucopyranosidc (1) and (25S) spirost-5-en-3β, 17α, 27-triol-3-O-[α-L-arabinopyranosyl(1-6)]-β-D-glucopyranosidc (2) were isolated from the roots of Smilax lebrunii.Theirstructures were established on thc basis of chemical and spectral methods
Two new minor steroidal saponins, (25R) spirostan-3β-ol-6-one-3-O-[α-L-arabinopyranosyl(1-4)]-β-D-glucopyranosidc (1) and (25S) spirost-5-en-3β, 17α, 27-triol-3-O-[α-L-arabinopyranosyl(1-6)]-β-D-glucopyranosidc (2) were isolated from the roots of Smilax lebrunii.Theirstructures were established on thc basis of chemical and spectral methods
1992, 3(6): 433-434
Abstract:
A new steroidal alkaloid, vaganine A (1) was isolated togetherwith a known compound paohysandrine A (2) from Sarcooocca vagans.Theirstructures were determined by spectroscopic evidence
A new steroidal alkaloid, vaganine A (1) was isolated togetherwith a known compound paohysandrine A (2) from Sarcooocca vagans.Theirstructures were determined by spectroscopic evidence
1992, 3(6): 435-436
Abstract:
A new diterpene lactone with an ent--kaurane skeleton, named antriptolactone(1)was isolated from the roots of Tripterygium wilfordii cellected in Anhui province.Its structurewas elucidated by spectral data and chemical transformtion
A new diterpene lactone with an ent--kaurane skeleton, named antriptolactone(1)was isolated from the roots of Tripterygium wilfordii cellected in Anhui province.Its structurewas elucidated by spectral data and chemical transformtion
1992, 3(6): 437-440
Abstract:
The through--space and through--bond interactions in 1, 5--Cyclooctadiyne arestudied.It is shown, with the assistance of improved MS--Xα method, that the through- spaceinteractions decrease with the distance of the orbitals, and both through--space and through--bondinteractions of 1, 5-Cyclooctadiyne are sizable but those two interactions oppose each othercausing the net splitting to be small for πz orbital.The calculated ionization potentials are in goodagreement with the experiment of photoelectron spectra
The through--space and through--bond interactions in 1, 5--Cyclooctadiyne arestudied.It is shown, with the assistance of improved MS--Xα method, that the through- spaceinteractions decrease with the distance of the orbitals, and both through--space and through--bondinteractions of 1, 5-Cyclooctadiyne are sizable but those two interactions oppose each othercausing the net splitting to be small for πz orbital.The calculated ionization potentials are in goodagreement with the experiment of photoelectron spectra
1992, 3(6): 441-444
Abstract:
Based on Xα multiple scattering one-electron wave functions, a way for solvingthe many-electron Schrödinger equation by means of irreducible tensor method is reported.As anapplication, the analysis of the spectra of molecule NIF64- is presented
Based on Xα multiple scattering one-electron wave functions, a way for solvingthe many-electron Schrödinger equation by means of irreducible tensor method is reported.As anapplication, the analysis of the spectra of molecule NIF64- is presented
1992, 3(6): 445-448
Abstract:
The frontier orbitals HOMO and LUMO of the fullerene C60 hasbeen given in a system of 60 motion-coordinates, of which each origin is ateach C atom of fullerene C60 and each z-axis is in the directionperpendicular to C60'S spherical surface.In this motion-coordinate systemthe HOMO and LUMO of fullerene C60 obviously display characteristics ofspherical n-molecular orbitals πn.The Fenske-Hall quantum-chemical methodis used in calculation for the electronic structure of the fullerene C60
The frontier orbitals HOMO and LUMO of the fullerene C60 hasbeen given in a system of 60 motion-coordinates, of which each origin is ateach C atom of fullerene C60 and each z-axis is in the directionperpendicular to C60'S spherical surface.In this motion-coordinate systemthe HOMO and LUMO of fullerene C60 obviously display characteristics ofspherical n-molecular orbitals πn.The Fenske-Hall quantum-chemical methodis used in calculation for the electronic structure of the fullerene C60
1992, 3(6): 449-452
Abstract:
This paper presents a new method called improved oscillographicchronopotcntiometry.It changes the incision of dE/dt-E curve into a peak shape and hasthe advantages of good reproducibility and wider linear range
This paper presents a new method called improved oscillographicchronopotcntiometry.It changes the incision of dE/dt-E curve into a peak shape and hasthe advantages of good reproducibility and wider linear range
1992, 3(6): 453-456
Abstract:
A simple method for determining the inverse current of cyclic voltammetry inthe processes of steady-state or quasi-steady-state was presented.The experimental resultverified the theoretical relation or inverse and forward current at microelectrode.Their ratio isproportional to the square root of scan rat
A simple method for determining the inverse current of cyclic voltammetry inthe processes of steady-state or quasi-steady-state was presented.The experimental resultverified the theoretical relation or inverse and forward current at microelectrode.Their ratio isproportional to the square root of scan rat
1992, 3(6): 457-458
Abstract:
A novel β-cyclodextrin derivative, 2, 6-di-O-butyl-3-O-acetyl-β-cyclodex-trin, was prepared and used as chiral stationary phase for capillary gas chromato-graphic resolution of enantiomers, lhe glass capillary columns with the derivativehaving low melting point and high thermal stability could produce more than 3000plates per column meter and have proven to be good chlral columns to separate theenantiomers of some amino acids, derivatives of epoxy ethane and alkyl halide, etc
A novel β-cyclodextrin derivative, 2, 6-di-O-butyl-3-O-acetyl-β-cyclodex-trin, was prepared and used as chiral stationary phase for capillary gas chromato-graphic resolution of enantiomers, lhe glass capillary columns with the derivativehaving low melting point and high thermal stability could produce more than 3000plates per column meter and have proven to be good chlral columns to separate theenantiomers of some amino acids, derivatives of epoxy ethane and alkyl halide, etc
1992, 3(6): 459-462
Abstract:
A hexamolybdenum complex, [Et4N]2[Mo6O19H4] crystal, withpentavalent and hexavalent molybdenum has been obtained in the solution ofDMF and CH3OH as organic solvents using MoCl5 as a starting material.Thecrystallographic parameters obtained by X-ray diffraction analysis are:crthorhombic, a=10.757(3), b=10.763(2), c=14.238(4)Å, =1648.9Å3; Z=2; spacegroup Pnnm; final R=0.047; final Rw=0.051**
A hexamolybdenum complex, [Et4N]2[Mo6O19H4] crystal, withpentavalent and hexavalent molybdenum has been obtained in the solution ofDMF and CH3OH as organic solvents using MoCl5 as a starting material.Thecrystallographic parameters obtained by X-ray diffraction analysis are:crthorhombic, a=10.757(3), b=10.763(2), c=14.238(4)Å, =1648.9Å3; Z=2; spacegroup Pnnm; final R=0.047; final Rw=0.051**
1992, 3(6): 463-464
Abstract:
The effects of concentration, temperature, stirring rate and specific interfacial area onthe extraction of Pd (Ⅱ) with bis(2--ethylhexyl) sulfide (DEHS) were studied by the use of aconstant interracial area cell.The results support an interracial chemical reaction regime
The effects of concentration, temperature, stirring rate and specific interfacial area onthe extraction of Pd (Ⅱ) with bis(2--ethylhexyl) sulfide (DEHS) were studied by the use of aconstant interracial area cell.The results support an interracial chemical reaction regime
1992, 3(6): 465-466
Abstract:
In this paper, we propose the use of the molar absorbance/potential ratio to measure quantitatively the sensitivity of response signalof SEC cell and the system under study.A simple equation was developed, andthe major factors influencing the sensitivity were also assessed.Theresults obtained this way were in good agreement with actual cases
In this paper, we propose the use of the molar absorbance/potential ratio to measure quantitatively the sensitivity of response signalof SEC cell and the system under study.A simple equation was developed, andthe major factors influencing the sensitivity were also assessed.Theresults obtained this way were in good agreement with actual cases
1992, 3(6): 467-470
Abstract:
The investigation of the esterolysis of p-nitrophenol acetate (PNPA) catalyzedby alginate-cobalt(Ⅱ) complex membrane was carried out under various conditions.Theresults showed that the pseudo-first-order plots of the hydrolyses of PNPA catalyzed byalginate-Co(Ⅱ) complex membrane were linear.The kinetic constants were obtained andshowed that the hydrolysis reactions obeyed Michaelis-Menten equations, showing anenzyme-like catalytic function of the membrane
The investigation of the esterolysis of p-nitrophenol acetate (PNPA) catalyzedby alginate-cobalt(Ⅱ) complex membrane was carried out under various conditions.Theresults showed that the pseudo-first-order plots of the hydrolyses of PNPA catalyzed byalginate-Co(Ⅱ) complex membrane were linear.The kinetic constants were obtained andshowed that the hydrolysis reactions obeyed Michaelis-Menten equations, showing anenzyme-like catalytic function of the membrane
1992, 3(6): 471-472
Abstract:
An optical transmission method was used in-situ to measure therate of pyrolytic deposition from Mn2(CO)10 induced by a CW CO2 laser.Theeffect of the laser intensity, Mn2(CO)10 vapor pressure and addedgases (CO, O2 and Ar) on the deposition rate has been examined
An optical transmission method was used in-situ to measure therate of pyrolytic deposition from Mn2(CO)10 induced by a CW CO2 laser.Theeffect of the laser intensity, Mn2(CO)10 vapor pressure and addedgases (CO, O2 and Ar) on the deposition rate has been examined
1992, 3(6): 473-476
Abstract:
Four new types of microporous beryllophosphates werehydrothermally synthesized using BeO- P2O5- R- MCl (or MCl2)- H20, Rbeing HMDA (1, b-hexanediamine), EDA (ethylenediamine), or TBAOH(tetrabutytamine hydroxide), M alkali or alkali earth cation.By means ofX-ray diffraction patterns (XRD), infrared (IR), TG-DT and elemental analyseswe show that the crystalline beryllopbospbates have novel, unique frameworkstructures, composed from basic units of tetrahedral P04 and Be04.Thesematerials exhibit zeolite-like adsorption and ion-exchange properties
Four new types of microporous beryllophosphates werehydrothermally synthesized using BeO- P2O5- R- MCl (or MCl2)- H20, Rbeing HMDA (1, b-hexanediamine), EDA (ethylenediamine), or TBAOH(tetrabutytamine hydroxide), M alkali or alkali earth cation.By means ofX-ray diffraction patterns (XRD), infrared (IR), TG-DT and elemental analyseswe show that the crystalline beryllopbospbates have novel, unique frameworkstructures, composed from basic units of tetrahedral P04 and Be04.Thesematerials exhibit zeolite-like adsorption and ion-exchange properties
1992, 3(6): 477-478
Abstract:
The azeotrope disappeared when the formic acid-water mixtureswere treated by membrane distillation.Membrane distillation were used forseparation of formic acid-water azeotropic mixtures for the first time
The azeotrope disappeared when the formic acid-water mixtureswere treated by membrane distillation.Membrane distillation were used forseparation of formic acid-water azeotropic mixtures for the first time
1992, 3(6): 479-482
Abstract:
Conductivities of Langmuir-Blodgett(LB) films of tetrabenzylthio-tetra-thiafulvalence-Ni(dmit)2/stearic acid (SA)were described.This chargetransfer complex was transferred with SA onto a glass plate coated with A1electrodes.The relation of conductivities of LB films with molar ratio ofSA was studied.The conductivities of LB films of TBT-TTF-Ni(dmit)2/SA weremeasured under undoped and I2 doped states.The maximum conductivity （σ,’）of LB film was 40s/cm
Conductivities of Langmuir-Blodgett(LB) films of tetrabenzylthio-tetra-thiafulvalence-Ni(dmit)2/stearic acid (SA)were described.This chargetransfer complex was transferred with SA onto a glass plate coated with A1electrodes.The relation of conductivities of LB films with molar ratio ofSA was studied.The conductivities of LB films of TBT-TTF-Ni(dmit)2/SA weremeasured under undoped and I2 doped states.The maximum conductivity （σ,’）of LB film was 40s/cm
1992, 3(6): 483-484
Abstract:
The kineties of non-isothermal crystallization of Nylon-1010 has been investigated by usingdifferential scanning calorimetry(DSC), DSC curves were obtained under cooling rate(R):2.5, 5, 10, 20, 40K/min.Applying Mandelkern and Ziabicki theories, the values of the Z kinetic parameter and G the kinetic crystalllzab-ility have been determined.Expenents of Avrami obtained in this work decrease with increase of coolingrate and then level off.The experimental results show disagreements with the Ozawa equation
The kineties of non-isothermal crystallization of Nylon-1010 has been investigated by usingdifferential scanning calorimetry(DSC), DSC curves were obtained under cooling rate(R):2.5, 5, 10, 20, 40K/min.Applying Mandelkern and Ziabicki theories, the values of the Z kinetic parameter and G the kinetic crystalllzab-ility have been determined.Expenents of Avrami obtained in this work decrease with increase of coolingrate and then level off.The experimental results show disagreements with the Ozawa equation
