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1992 Volume 3 Issue 4
1992, 3(4): 235-236
Abstract:
dl-And (R)-muscone were synthesized from the readily available cyclododecanone by a free radical ring expansion in overall yields of 51% and 32% respectively
dl-And (R)-muscone were synthesized from the readily available cyclododecanone by a free radical ring expansion in overall yields of 51% and 32% respectively
1992, 3(4): 237-238
Abstract:
The title compounds were prepared by the enzymatic resolution of the corresponding N-acetylated DL-amino acids methyl esters, which were obtained from t-butyl chloride via an 8-step synthesis
The title compounds were prepared by the enzymatic resolution of the corresponding N-acetylated DL-amino acids methyl esters, which were obtained from t-butyl chloride via an 8-step synthesis
1992, 3(4): 239-240
Abstract:
The synthesis of new acyclic crown ethers 1, 2, and 3 with methimazole as terminal group is reported
The synthesis of new acyclic crown ethers 1, 2, and 3 with methimazole as terminal group is reported
1992, 3(4): 241-244
Abstract:
α-Oxoketene dithioacetals 2 via, 1,2-nucleophilic addition by allyl magnesium bromide afforded corresponding alcohols (3).Treated with water and catalyzed by Lewis acid, the alcohols 3 were converted regiospecifically to the conjugated 1,1-dialkylthio-1,3,5 hexatrienes (4). Both the alcohol 8 and its methoxy methyl ether 9 were sensative to dilute sulfuric acid and cyclized under this condition to form the aryl methylthio ether (10)
α-Oxoketene dithioacetals 2 via, 1,2-nucleophilic addition by allyl magnesium bromide afforded corresponding alcohols (3).Treated with water and catalyzed by Lewis acid, the alcohols 3 were converted regiospecifically to the conjugated 1,1-dialkylthio-1,3,5 hexatrienes (4). Both the alcohol 8 and its methoxy methyl ether 9 were sensative to dilute sulfuric acid and cyclized under this condition to form the aryl methylthio ether (10)
1992, 3(4): 245-246
Abstract:
A new vitamin B12 coenzyme analogue 2’,5’-dideoxyuridinyicobalamin and two other 2’,5’-dideoxynucleosidecobalamins of adenosyl-and thymidyl-were synthesized by an improved method, It consists in direct tosylation of the nucleoside and followed by reaction with reduced hydroxocobalamin(vitamin B12). All the 2’-deozynucleoside derivatives were characterized by UV-Vis and 1HNMR spectroscopy
A new vitamin B12 coenzyme analogue 2’,5’-dideoxyuridinyicobalamin and two other 2’,5’-dideoxynucleosidecobalamins of adenosyl-and thymidyl-were synthesized by an improved method, It consists in direct tosylation of the nucleoside and followed by reaction with reduced hydroxocobalamin(vitamin B12). All the 2’-deozynucleoside derivatives were characterized by UV-Vis and 1HNMR spectroscopy
1992, 3(4): 247-250
Abstract:
The ZnCl2-catalyzed condensation reaction of ferrocenealdehyde and indole in the solid state gave a new product (di-3-indolyi)-methylferrocene(3). The crystal structure of product 3 was determined by X-ray diffraction method. Reactions in solution and photochemical reactions were also carried out
The ZnCl2-catalyzed condensation reaction of ferrocenealdehyde and indole in the solid state gave a new product (di-3-indolyi)-methylferrocene(3). The crystal structure of product 3 was determined by X-ray diffraction method. Reactions in solution and photochemical reactions were also carried out
1992, 3(4): 251-252
Abstract:
The effects of the chain length and stereo-factor of substrates and solvents on the lipase catalysed lactonization of ω-hydroxy-ester were studied, And also the catalytic effects of various enzymes were compared
The effects of the chain length and stereo-factor of substrates and solvents on the lipase catalysed lactonization of ω-hydroxy-ester were studied, And also the catalytic effects of various enzymes were compared
1992, 3(4): 253-254
Abstract:
A new method for the synthesis of perbenzylated, peracetylated and perbenzoylated sugar nucleosides has been carefully studied. In this method trichloroacetoxy and trifluoroacetoxy groups were displaced efficiently in the reaction of nucleoside formation as leaving group. And this method was found to be widely applicable in the study of carbohydrate chemistry
A new method for the synthesis of perbenzylated, peracetylated and perbenzoylated sugar nucleosides has been carefully studied. In this method trichloroacetoxy and trifluoroacetoxy groups were displaced efficiently in the reaction of nucleoside formation as leaving group. And this method was found to be widely applicable in the study of carbohydrate chemistry
1992, 3(4): 255-256
Abstract:
The title complex (PtL2Cl2) was synthesized by reacting 10-selenabenzo-15-crown-5 (L) with potassium chloroplatinite. Its catalytic activity for the hydrosilylation of olefins by triethoxysilane, was investi gated
The title complex (PtL2Cl2) was synthesized by reacting 10-selenabenzo-15-crown-5 (L) with potassium chloroplatinite. Its catalytic activity for the hydrosilylation of olefins by triethoxysilane, was investi gated
1992, 3(4): 257-258
Abstract:
The reaction of benzyloxyethanol with carbon tetrabromide was investigated, and a possible mechanism was proposed
The reaction of benzyloxyethanol with carbon tetrabromide was investigated, and a possible mechanism was proposed
1992, 3(4): 259-262
Abstract:
Using potassium carbonate as base and a polyethylene glycol with an average molecular weight of 600 (PGE600) as phase transfer catalyst, reaction of benzyl ethers with dibromocarbene leads to benzylic C-H bond insertion products, aromatic aldehydes are also formed as one of the products
Using potassium carbonate as base and a polyethylene glycol with an average molecular weight of 600 (PGE600) as phase transfer catalyst, reaction of benzyl ethers with dibromocarbene leads to benzylic C-H bond insertion products, aromatic aldehydes are also formed as one of the products
1992, 3(4): 263-264
Abstract:
In the selective hydrogenation of diene (or alkyne) using heterogenized homogeneous catalyst, the high selectivity of monoene formation only appears in a very short time interval. The addition of suitable electron donors can decrease or even cease the monoene hydrogenation and thereby keep the high monoene selectivity after reaching its maximum
In the selective hydrogenation of diene (or alkyne) using heterogenized homogeneous catalyst, the high selectivity of monoene formation only appears in a very short time interval. The addition of suitable electron donors can decrease or even cease the monoene hydrogenation and thereby keep the high monoene selectivity after reaching its maximum
1992, 3(4): 265-266
Abstract:
The catalyzation of CoTPP for electrocarboxylation of alkyl halides, alkenes and ketones with CO2 are studied. The electrocarboxylation of these organic compounds with CO2 in the presenec of catalyst can occur at more positive potential than that of no catalyst. The products of electrocarboxylation were identified by UV, IR and GC-MS. The electrocarboxylation mechanisms of different organic compounds are discussed
The catalyzation of CoTPP for electrocarboxylation of alkyl halides, alkenes and ketones with CO2 are studied. The electrocarboxylation of these organic compounds with CO2 in the presenec of catalyst can occur at more positive potential than that of no catalyst. The products of electrocarboxylation were identified by UV, IR and GC-MS. The electrocarboxylation mechanisms of different organic compounds are discussed
1992, 3(4): 267-268
Abstract:
Oxidation of ethylbenzene, n-propylbcnzene and n-butylbenzene gives the corresponding ketones and alcohols in good yields by organic polymer supported low-valent Ru (Ⅱ) complexes under 1 atm. of air or oxygen at 100℃ in the absence of solvent. The calalytic selectivity to total ketone and alcohol ranged from 98.7％ to 100％. The polymer complex polymer-bipy-Ru-bipy (bipy=2, 2’-bipyridine) is very stable and can be reused for 5 times (each for 5h) without appreciable change in catalytic activity
Oxidation of ethylbenzene, n-propylbcnzene and n-butylbenzene gives the corresponding ketones and alcohols in good yields by organic polymer supported low-valent Ru (Ⅱ) complexes under 1 atm. of air or oxygen at 100℃ in the absence of solvent. The calalytic selectivity to total ketone and alcohol ranged from 98.7％ to 100％. The polymer complex polymer-bipy-Ru-bipy (bipy=2, 2’-bipyridine) is very stable and can be reused for 5 times (each for 5h) without appreciable change in catalytic activity
1992, 3(4): 269-270
Abstract:
Treatment of denudatine 1 with 10％ HCl soln. at 30-40℃ for 1 day leads to another rearrangement product 3 along with a pair of epimers 2A and 2B. Upon adding a little EtOH in the reaction solution, only a pair of epimers 4A and 4B were obtained along with the unchanged starting material
Treatment of denudatine 1 with 10％ HCl soln. at 30-40℃ for 1 day leads to another rearrangement product 3 along with a pair of epimers 2A and 2B. Upon adding a little EtOH in the reaction solution, only a pair of epimers 4A and 4B were obtained along with the unchanged starting material
1992, 3(4): 271-274
Abstract:
Alkaloids of balladonna plant were studied by molecular mechanics MMPM calculation. The results showed that the ideal conformation was quite different from the structure found in the crystals of the alkaloids in belladonna plant. The intramolecular hydrogen bond was present between the hydroxy group and carbonyl oxygen atom in the ideal conformation for these alkaloids. The origin of asymmetrical molecules in nature obeys the lowest energy principle. This may be a reason why only S-(-) not R-(+)-isomer, only hyoscyamine not pseudotropine were found to be present in natural belladonna plant, The model of four recognition sites between anticholinergic drug-receptor interaction in mydriasis was suggested, in which the hydroxy group with 8~9 A distanced from nitrogen atom is possibly necessary for maximum mydriasis activity
Alkaloids of balladonna plant were studied by molecular mechanics MMPM calculation. The results showed that the ideal conformation was quite different from the structure found in the crystals of the alkaloids in belladonna plant. The intramolecular hydrogen bond was present between the hydroxy group and carbonyl oxygen atom in the ideal conformation for these alkaloids. The origin of asymmetrical molecules in nature obeys the lowest energy principle. This may be a reason why only S-(-) not R-(+)-isomer, only hyoscyamine not pseudotropine were found to be present in natural belladonna plant, The model of four recognition sites between anticholinergic drug-receptor interaction in mydriasis was suggested, in which the hydroxy group with 8~9 A distanced from nitrogen atom is possibly necessary for maximum mydriasis activity
1992, 3(4): 275-278
Abstract:
The substituent effects on 31P-NMR chemical shifts, are determined by five empirical rules. The proposed rules are based on that the shielding (upfield shift) of resonance nucleus is governed by the spherical symmetry of the electron cloud
The substituent effects on 31P-NMR chemical shifts, are determined by five empirical rules. The proposed rules are based on that the shielding (upfield shift) of resonance nucleus is governed by the spherical symmetry of the electron cloud
1992, 3(4): 279-280
Abstract:
Treatment of aromatic α-hydroxy ketones with an activated Ti(O) reagent, prepared by reduction of TiCl3 with a Zn-Cu couple, effects an intermolecular coupling reaction leading to the (Z)-1, 2, 3, 4-tetrarvl-2-butene and (E, E)-1, 2, 3, 4,-tetraryl-1, 3-butadiene. A possible reaction mechanism was proposed
Treatment of aromatic α-hydroxy ketones with an activated Ti(O) reagent, prepared by reduction of TiCl3 with a Zn-Cu couple, effects an intermolecular coupling reaction leading to the (Z)-1, 2, 3, 4-tetrarvl-2-butene and (E, E)-1, 2, 3, 4,-tetraryl-1, 3-butadiene. A possible reaction mechanism was proposed
1992, 3(4): 281-282
Abstract:
From the whole plant of Cynomorium songaricum a new triterpene was isolated together with acetyl ursolic acid, ursolic acid, β-sitosterol palmitate, β-sitosterol, palmitic acid and β-sitosterol glucoside. The structure of the new compound was elucidated as ursa-12-ene-28-oic acid, 3β-propanedioic acid monoester (cynoterpene, 1)
From the whole plant of Cynomorium songaricum a new triterpene was isolated together with acetyl ursolic acid, ursolic acid, β-sitosterol palmitate, β-sitosterol, palmitic acid and β-sitosterol glucoside. The structure of the new compound was elucidated as ursa-12-ene-28-oic acid, 3β-propanedioic acid monoester (cynoterpene, 1)
1992, 3(4): 283-284
Abstract:
The phytochcmical investigation of the aerial parts of Artemisia feddei Levl. et Vant. gave a pair of novel C14 acetylenic spiroketals
The phytochcmical investigation of the aerial parts of Artemisia feddei Levl. et Vant. gave a pair of novel C14 acetylenic spiroketals
1992, 3(4): 285-286
Abstract:
Two new steroidal saponins, named macrostemonoside A and D. were isolated from the bhlbus of Allium macrostemon Bunge (Liliaceae), and their strurtures were established by spectroscopic analysis and chemical evidences
Two new steroidal saponins, named macrostemonoside A and D. were isolated from the bhlbus of Allium macrostemon Bunge (Liliaceae), and their strurtures were established by spectroscopic analysis and chemical evidences
1992, 3(4): 287-288
Abstract:
A new naturally occurring compound 1-polyacetylene glycoside has been isolated form the n-butanol soluble fraction of the leaves of Bidens bipinnata. The chemical structure of 1 was shown to be 3E, 11E-Diethenylene 5. 7. 9-triacetylene, 1, 13-tridecanglycol-2-O-β-D-glycoside named bipinnatpolyacetyloside according to spectral analyses of UV. IR. FDMS, 1H-NMR, H-H COSY, 13C-NMR and DEPT
A new naturally occurring compound 1-polyacetylene glycoside has been isolated form the n-butanol soluble fraction of the leaves of Bidens bipinnata. The chemical structure of 1 was shown to be 3E, 11E-Diethenylene 5. 7. 9-triacetylene, 1, 13-tridecanglycol-2-O-β-D-glycoside named bipinnatpolyacetyloside according to spectral analyses of UV. IR. FDMS, 1H-NMR, H-H COSY, 13C-NMR and DEPT
1992, 3(4): 289-290
Abstract:
A new triterpene saponin; 3-0-{β-D-xylopyranosyl(1-2) [β-D-glucuronopyranosyl(1-3)]}β-D-glucopyranosyl-oleanolic acid (Ⅲ) along with two known triterpene saponins has been isolated from the root of Aralia spinifolia. Their structures have been elucidated by spectral analysis and chemical methods
A new triterpene saponin; 3-0-{β-D-xylopyranosyl(1-2) [β-D-glucuronopyranosyl(1-3)]}β-D-glucopyranosyl-oleanolic acid (Ⅲ) along with two known triterpene saponins has been isolated from the root of Aralia spinifolia. Their structures have been elucidated by spectral analysis and chemical methods
1992, 3(4): 291-292
Abstract:
The structure and properties of Sm complex with β-alanine have been studied by quantum chemical calculation, The theoretical result agree well with the experimental ones obtained in studies on rare earth complexes with amino acids
The structure and properties of Sm complex with β-alanine have been studied by quantum chemical calculation, The theoretical result agree well with the experimental ones obtained in studies on rare earth complexes with amino acids
1992, 3(4): 293-294
Abstract:
Lanthanide complexes of acetylacetonate-meso-5-(4-hydroxy)-10,15,20,trimethoxyphenylporphyrin, Ln(HMpp)acac (Ln=Dy, Er, H=hydroxy group, M=methoxy group, hacac=acetylacetone, pp=phenylporphyrin) have been prepared and characterized on the basis of elemental analyses, infrared spectra, and ultra-violet visible spectra
Lanthanide complexes of acetylacetonate-meso-5-(4-hydroxy)-10,15,20,trimethoxyphenylporphyrin, Ln(HMpp)acac (Ln=Dy, Er, H=hydroxy group, M=methoxy group, hacac=acetylacetone, pp=phenylporphyrin) have been prepared and characterized on the basis of elemental analyses, infrared spectra, and ultra-violet visible spectra
1992, 3(4): 295-298
Abstract:
Five solid complexes of rare earth with L-methionine have been prepared. The interaction of rare earth with the ligand has been studied by NMR and IR spectroscopy
Five solid complexes of rare earth with L-methionine have been prepared. The interaction of rare earth with the ligand has been studied by NMR and IR spectroscopy
1992, 3(4): 299-300
Abstract:
A highly sensitive and fairly selective spectrofluorimetric method has been developed for the determination of germanium with morin in tap water and health drink. The fluorescent reaction and optimal conditions of germanium with morin in phosphoric acid medium were studied. The detection limits of germanium in tap water and health drink were found to be 0.2 and 0.7μd/L respectively
A highly sensitive and fairly selective spectrofluorimetric method has been developed for the determination of germanium with morin in tap water and health drink. The fluorescent reaction and optimal conditions of germanium with morin in phosphoric acid medium were studied. The detection limits of germanium in tap water and health drink were found to be 0.2 and 0.7μd/L respectively
1992, 3(4): 301-302
Abstract:
A new ELM was prepared for the study on transport of Mo(Ⅵ) ion. Under the experimental conditions, Mo(Ⅵ) can be transported completely and separated from the co-lons.The emulsion liquid membrane(ELM) with Tri-n-octylamine(TOA) as a carrie[1-3] used for the transport of Mo(Ⅵ) ions and its separation from some cations have been reported in this paper. The transport percentage of Mo(Ⅵ) ion through ELM in 5 min corresponds to that of the literature[3] in 165 min
A new ELM was prepared for the study on transport of Mo(Ⅵ) ion. Under the experimental conditions, Mo(Ⅵ) can be transported completely and separated from the co-lons.The emulsion liquid membrane(ELM) with Tri-n-octylamine(TOA) as a carrie[1-3] used for the transport of Mo(Ⅵ) ions and its separation from some cations have been reported in this paper. The transport percentage of Mo(Ⅵ) ion through ELM in 5 min corresponds to that of the literature[3] in 165 min
1992, 3(4): 303-304
Abstract:
In situ x-ray diffraction electrochemical method is used to study the activation of silver electrode in KCl solution and UPD lead on silver electrode surface. We found that the activation makes the silver crystal thicker in (111), and the arrangement of water molecules on the silver electrode surface with UPD lead is partially ordered
In situ x-ray diffraction electrochemical method is used to study the activation of silver electrode in KCl solution and UPD lead on silver electrode surface. We found that the activation makes the silver crystal thicker in (111), and the arrangement of water molecules on the silver electrode surface with UPD lead is partially ordered
1992, 3(4): 305-306
Abstract:
The redox behaviours of a donor-acceptor model compound. p-tricyano-ethenyl-N, N-dimethyl aniline was investigated by electrochemical and spectroelectrochemical methods. The results indicate that charge transfer between the donor(amino) and the acceptor(cyanoethenyl) groups takes place in the process of oxidation of this compound
The redox behaviours of a donor-acceptor model compound. p-tricyano-ethenyl-N, N-dimethyl aniline was investigated by electrochemical and spectroelectrochemical methods. The results indicate that charge transfer between the donor(amino) and the acceptor(cyanoethenyl) groups takes place in the process of oxidation of this compound
1992, 3(4): 307-310
Abstract:
Starting from camphene and NBS the 1-bromomethyl-7, 7-dimethylblcyclo-[2.2.1]hept-2-yl acrylate [BMCHA] has been synthesized by two steps. The polymerization kinetics equation of this monomer was obtained as follows:Rp=K[BPO]0.50[BMCHA]1.0 and the apparent activation energy of the polymerization was evaluated to be 82.96KJ/mol
Starting from camphene and NBS the 1-bromomethyl-7, 7-dimethylblcyclo-[2.2.1]hept-2-yl acrylate [BMCHA] has been synthesized by two steps. The polymerization kinetics equation of this monomer was obtained as follows:Rp=K[BPO]0.50[BMCHA]1.0 and the apparent activation energy of the polymerization was evaluated to be 82.96KJ/mol
1992, 3(4): 311-314
Abstract:
Under steady-state conditions, using the concept of steady-state reaction layer, the general currents of ECE and DISP1 reactions at microdisk electrode are derived. From these equations, some kinetic and electrode reaction parameters can be obtained
Under steady-state conditions, using the concept of steady-state reaction layer, the general currents of ECE and DISP1 reactions at microdisk electrode are derived. From these equations, some kinetic and electrode reaction parameters can be obtained
1992, 3(4): 315-318
Abstract:
The electrochemi luminescence of a new reagent 6-<2-hydroxy-4-diethylaminophenylazo>-2, 3-dihydro-1, 4-phthatazine-1, 4-dione in basic aqueous solution was studied. Trace amount of silver(I) showed significant effect on the efficiency of light emission of HDEA during a positive trigonometrical wave pulse was exerted on the electrodes In the present paper, the ecl spectra of HDEA have been measured. λmax is 410 nm. The reaction of HDEA chemiluminescence and the circular voltammetry, ultraviolet-visible spectrometry for the system have been investigated. The possible mechanism of the ecl of HDEA-KCL-KOH-Ag(I) system has been proposed
The electrochemi luminescence
REDUCED EXTENT METHOD FOR THERMOKINETICS Ⅰ. MATHEMATICAL MODELS FOR KINETICS OF REVERSIBLE REACTIONS
1992, 3(4): 319-322
Abstract:
Some new mathematical models of reversible reaction kinetics have been suggested, and a reduced extent method for studies of thermokinetics of reversible reactions has been proposed
Some new mathematical models of reversible reaction kinetics have been suggested, and a reduced extent method for studies of thermokinetics of reversible reactions has been proposed
1992, 3(4): 323-324
Abstract:
A novel electrochromic display composed of polymeric solid electrolyte and ferroin electroactive species has been assembled, which presents a reversible variation of the color between light blue and red when a potential of 0.98 and 0.75 V is applied respectively. The results indicate that the response speed is increased by lowering the concentration of ferroin without decreasing color contrast
A novel electrochromic display composed of polymeric solid electrolyte and ferroin electroactive species has been assembled, which presents a reversible variation of the color between light blue and red when a potential of 0.98 and 0.75 V is applied respectively. The results indicate that the response speed is increased by lowering the concentration of ferroin without decreasing color contrast
1992, 3(4): 325-328
Abstract:
Using ethylenediamine as template, we have hydrothermally synthesized three new microporous aluminophosphate crystals which were named AlPO4-CJ3, AlPO4-CJ6, AlPO4-CJ7, and characterized by means of X-ray powder diffraction, infrared spectroscopy, SEM, 13C solid state NMR and TG-DTA techniques
Using ethylenediamine as template, we have hydrothermally synthesized three new microporous aluminophosphate crystals which were named AlPO4-CJ3, AlPO4-CJ6, AlPO4-CJ7, and characterized by means of X-ray powder diffraction, infrared spectroscopy, SEM, 13C solid state NMR and TG-DTA techniques
