Showing papers in "Journal of The Chinese Chemical Society in 1978"
TL;DR: In this paper, the pyridylidene structure of 4-methylpyridine and its methiodide with p-N, N-dimethylamino-benzaldehyde gave 4-p-N.
Abstract: The reaction of 4-methylpyridine and its methiodide with p-N, N-dimethylamino-benzaldehyde gave 4-p-N, N-dimethylaminostyrylpyridine (I) and 4-p-N, N-dimethylaminostyrylpyridine methiodide (II), respectively, II was also prepared by methylation of I with methyl iodide in methanol. The pyridylidene structure of II, N-benzyl-4-(p-N, N-dimethylaminophenyl) pyridinium chloride (IVa) and its methiodide (Va) was discussed in terms of UV, NMR and mass spectra.
17 citations
TL;DR: Results show that papain is a good catalyst for oligopeptide synthesis in reasonable yield after recystallization and an optical purity as high as 98.6%.
Abstract: Eighteen Z-X-Y-OTNB+ type dipeptides, four Z-Val-Cys(Bzl)-X-OTMB tripeptides and a tetrapeptide Z-Val-Cys(Bzl)-Cys(Bzl)-Asn-OTMB have been synthesized by papain-catalyzed reaction in reasonable yield after recystallization. Z-DL-Ala-OH has been resolved through papain-catalyzed synthesis of Z-L-Ala-Leu-OTMB with an optical purity as high as 98.6%. These results show that papain is a good catalyst for oligopeptide synthesis.
9 citations
TL;DR: In this article, a new numerical method for isolating component spectra from spectra of their mixtures is presented, which is based on a risk function which assigns a relative value for the risk to regard a spectral shape as that of a pure substance.
Abstract: A new numerical method for isolating component spectra from spectra of their mixtures is presented. The method searches the component spectra by optimizing a risk function which assigns a relative value for the risk to regard a spectral shape as that of a pure substance. No prior knowledge of the nature of existing components is required in the analysis. All components conceivable in the set of mixture spectra are simultaneously isolated.
8 citations
TL;DR: The photoreaction mechanism of isoniazid in methanol and ethanol were discussed and the isolated and identified isonicotinaldehyde isonicOTinyl hydrazone was identified.
Abstract: The UV light irradiation of isoniazid (I) in methanol four products, isonicotinic acid (II), isonicotinamide (III), N, N′-bis(isonicotinic acid)hydrazide (IV) and isonicotinaldehyde isonicotinyl hydrazone (V), in ethanol three products, (III), (IV) and acetaldehyde isonicotinyl hydrazone (VI) were isolated and identified. Also, the photoreaction mechanism of isoniazid in methanol and ethanol were discussed.
5 citations
TL;DR: Under the irradiation of the ultraviolet light, Isoeugenol (I) undergoes dimerization in acetone to give diisoeugenol(II) and dehydrodiisoeogenol (III) as discussed by the authors, the structures are determined by the comparison of the mixed m. p., I. R. spectra and T. C. with synthesized authentic samples.
Abstract: Under the irradiation of the ultraviolet light, Isoeugenol (I) undergoes dimerization in acetone to give diisoeugenol (II) and dehydrodiisoeugenol (III). The structures are determined by the comparison of the mixed m. p., I. R. spectra and T. L. C. with synthesized authentic samples. Also the photoreaction mechanism is discussed in detail. The reaction represents a new type and as an exception of photochemical process for the C=C double bond in conjugation with aromatic ring that generally dimerizes to produce cyclobutane type derivatives.
5 citations
TL;DR: From the hexane and acetone extractive of the wood of Keteleeria davidiana Beissner, straight chain saturated hydrocarbons (C13, C14, C17-C14) were also obtained.
Abstract: From the hexane and acetone extractive of the wood of Keteleeria davidiana Beissner, α-pinene, β-pinene, limonene, α-copaene, bornyl acetate, β-elemene, caryophyllene, caryophyllene oxide, α-selinene, β∼selinene, selin-11-en-4α-o1, laevojunenol, α-cyperone, stigmasterol, β-sitosterol, tetracosyltetracosanoate, docosanyl tetracosanoate, hexacosanyltetracosanoate, tetracosanol, hexacosanol, docosanol, α-conidendrin and 15-hydroxydehydroabietic acid were isolated Straight chain saturated hydrocarbons (C13, C14, C17-C14) were also obtained
5 citations
TL;DR: In this article, a chromogenic reagent which contains ortho-phenanthroline-EDTA mixture has been developed to decrease the interference of ferric ion after adjusting the acidity of sample at 0.1 N by adding the sulfuric acid.
Abstract: The determination of trace iron(II) is usually interfered by the presence of iron(III) when ortho-phenanthroline colorimetric method is used. In this report a chromogenic reagent which contains ortho-phenanthroline-EDTA mixture has been developed to decrease the interference of ferric ion after adjusting the acidity of sample at 0.1 N by adding the sulfuric acid.
The procedure is also simplified by introducing sulfamate buffer solution (pH= 1.5) without adjusting the acidity of sample with sulfuric acid. If iron(III) is not present in the sample, this method is also applicable. The comparative results are exhibited for the present method and the conventional o-phenanthroline method.
4 citations
TL;DR: In this paper, the base-catalyzed elimination of β-chlorosulfones was used to obtain (E)-1-Alkanesulfonyl- and (E]-1-arylsulfonyls-2-phenylethenes (styryl sulfones).
Abstract: (E)-1-Alkanesulfonyl- and (E)-1-arylsulfonyl-2-phenylethenes (styryl sulfones) were obtained from good to excellent yields by the base-catalyzed elimination of the corresponding β-chlorosulfones. The latter were obtained, respectively, by additions of the alkanesulfonyl- and the arylsulfonyl chlorides to styrene under the catalytic action of copper chlorides.
4 citations
TL;DR: In this paper, 0.25 M of cystine in 1.5 N HC1 as cathode solution was divided by anion-exchange membrane from anode solution (1.5N HC1).
Abstract: Cysteine hydrochloride was prepared by electroreduction of cystine with stainless steel plate as electrodes. 0.25 M of cystine in 1.5 N HC1 as cathode solution was divided by anion-exchange membrane from anode solution (1.5 N HC1). A current of 5.6 A/S was applied and at the end of reaction, crysteine hydrochloride was obtained by evaporation of the cathode solution. The method is more convenient than the existing method.
4 citations
TL;DR: The Ni(RC6H4COO)2L2 complex of nickel(II) aryl carboxylates has been shown to be soluble in common organic solvents as mentioned in this paper.
Abstract: Complexes of nickel(II) aryl carboxylates with a general formula Ni(RC6H4COO)2L2 where R=H, p-CH3. p-Cl, m- & p-NO2; and L = morpholine and piperidine; have been prepared by the interaction of nickel(II) aryl carboxylates with a large excess of appropriate amine. Unlike parent anhydrous nickel(II) aryl carboxylates all these complexes are soluble in common organic solvents.
3 citations
TL;DR: In this paper, the mechanisms of unpaired electron spin delocalization in Co(II) complexes are discussed, and it is found that a σ-delocalization mechanism is in dominant, but the π-contribution can not be ruled out.
Abstract: The proton nmr isotropic shifts of pyridine type ligands coordinated to paramagnetic nickel(II) and cobalt(II) acetylacetonate are reported, and the mechanisms of unpaired electron spin delocalization in these complexes are discussed. It is found that a σ-delocalization mechanism is in dominant, but the π-contribution can not be rule out. The calculations of the geometric factor for Co(II) complexes are done. It is used in the ratio method to separate the contribution of pseudo-contact shift from isotropic shift for Co(II) complexes. The effect of pseudoaromatic chelate ring on contact shift is not so large as previously reported.
TL;DR: In this paper, dilithium derivatives of ketoximes react with alkyl halides to give α-substituted oximes, and the product oximes are the less stable (Z-) oximes.
Abstract: Dilithium derivatives of ketoximes react with alkyl halides to give α-substituted oximes. The dilithium derivatives are proposed to involve chelate formation. And the product oximes are the less stable (Z-) oximes.
TL;DR: In this article, the reaction of biscyclopentadienyl niobium(IV) dichloride and bisindenyl ndichloride with sodium or potassium salts of various pseudohalides have been studied.
Abstract: Reactions of biscyclopentadienyl niobium(IV) dichloride and bisindenyl niobium(IV) dichloride with sodium or potassium salts of various pseudohalides have been studied and the pseudohalide complexes so formed of the formulae (C5H5)2Nb(Ps)2 and (C2H7)2Nb(Ps)2 where Ps may be NC, NCO, NCS, or N3, have been isolated. The complexes have been characterised on the basis of physical measurements, analytical data and infrared spectral studies.
TL;DR: The axial CD spectra of a single crystal of Zn(en)3(NO3)2 doped with 1-50% Ni(en),3 (NO3),2 have been observed at temperatures from ambient to 5 K as discussed by the authors.
Abstract: The axial CD spectra of single crystal of Zn(en)3(NO3)2 doped with 1-50% Ni(en)3(NO3)2 have been observed at temperatures from ambient to 5 K. The increase in R of the 3E[3T3g(F)] transition as the temperature decreases is consistent with the magnetic dipole allowed character of the parent octahedral transition. The electric and magnetic dipole forbidden transition to the 3T1g(F) octahedral level gives rise to a relatively weak axial CD band with an unusual temperature dependent splitting. This structure is attributed to electric quadrupole intensity, which is allowed for transitions to both the E and 3A2[3T1g(F)] levels in D3 symmetry.
TL;DR: In this paper, the effect of temperature, agitation, and content of gold in the solution on the thickness of electroplated gold at various current densities can be easily explained by their effect on the limiting current.
Abstract: The effect of temperature, agitation, and content of gold in the solution on the thickness of electroplated gold at various current densities can be easily explained by their effect on the limiting current. Diffusion coefficient of aurocyanide ion, thickness of diffusion layer, and the activity of aurocyanide ion in the bulk solution are the three major factors to affect the limiting current. It was found that the change of temperature will affect both diffusion coefficient and thickness of diffusion layer. However, the thickness of diffusion layer is mainly determined by the means of agitation.
TL;DR: In this article, the reactions of oligomeric difluorosilylenes with cis-and trans-difluoroethylene are studied and the stereochemistry suggests an integrated reaction mechanism in which both addition and insertion pathways share a common diradical transition state.
Abstract: The reactions of oligomeric difluorosilylenes with cis -and trans -difluoroethylene are studied. All six new products are characterized and the stereochemistry suggests an integrated reaction mechanism in which both addition and insertion pathways share a common diradical transition state.
TL;DR: From the hexane extractive of the wood of Pinus luchuensis Mayer, α-pinene, β-pinenes, camphene, camphor, 4-terpineol and carvacrol were isolated.
Abstract: From the hexane extractive of the wood of Pinus luchuensis Mayer, α-pinene, β-pinene, camphene, camphor, 4-terpineol, α-terpineol, carvacrol, tetracosanol, hexacosanol, octacosanol, β-sitosterol, stigmasterol, methyl dehydroabietate, pinosylvin monomethylether, pimaric acid, dehydroabietic acid and straight chain hydrocarbons C23-C35 were isolated.
TL;DR: In this paper, the stability constants for the formation of [Cu(tet a)X]+(blue) from [Cu (tet b)X]+ (blue) and X- (where X=Cl, Br, I) were determined by spectrophotometric method at 15°, 25° and 35°C.
Abstract: The stability constants for the formation of [Cu(tet a)X]+(blue) from [Cu(tet a)]2+(blue) and X- (where X=Cl, Br, I) were determined by spectrophotometric method at 15°, 25° and 35°C. The corresponding ΔH° and ΔS° values were obtained from the variations of the stability constants between 15° and 35°C. For the same halide ion, the stability constant of [Cu(tet b)X]+ (blue) is larger than that of [Cu(tet a)X]+(blue).
TL;DR: In this paper, it was inferred that the structures for iron(II) dichloride with monoacetyl and 1, 1′-diacetylferrocence thiosemicarbazone are monomer and polymer respectively.
Abstract: Complexes of iron(II) dichloride with monoacetyl and 1, 1′-diacetylferrocence thiosemicarbazone have been prepared and characterized by means of optical spectra and magnetic measurement, and these structures have been investigated by Mossbauer spectra It is inferred that the structures for iron(II) complexets of monoacetylferrocence thiosemicarbazone and 1, 1′-diacetylbis (thiosemicarbazone) are monomer and polymer respectively
TL;DR: In this article, six new complexes of thallium(III) of the formula (π-D)2Tl(L) (where D= cyclopentadienyl or indenyl group and L=nitro, nitrito or nitrato group) have been prepared and characterised on the basis of I. R. studies and some thermal properties of these complexes.
Abstract: Six new complexes of thallium(III) of the formula (π-D)2Tl(L) (where D= cyclopentadienyl or indenyl group and L=nitro, nitrito or nitrato group) have been prepared and characterised on the basis of I. R. studies and some thermal properties of these complexes.
TL;DR: In this article, binuclear bridged complexes of composition Cu2(RC6H4COO)2L2 are regarded as binuclear bridges of composition, where R is o-, m-, p-CH2; o-,m-Cl: o-NO2; m-,p-CH 2O; and L is 2-, 3-, and 4-picNO ligand.
Abstract: Copper(II) aryl carboxylates on interaction with 2-picoline N-Oxide (2-picNO), 3-picoline N-Oxide (3-picNO) and 4-picoline N-Oxide (4-picNO) in acetone or ethyl acetate yield 1:1 adducts. These are regarded as binuclear bridged complexes of composition Cu2(RC6H4COO)2L2 where R is o-, m-, p-CH2; o-, m-Cl: o-NO2; m-, p-CH2O; and L is 2-, 3-, and 4-picNO ligand. With 4-picNO some 1:2 adducts have also been obtained.
TL;DR: A series of N-homocyclyl carbamoyl derivatives of maleamic acid and maleimide was prepared for hypocholesteremic and sulfhydryl-binding tests.
Abstract: A series of N-homocyclylcarbamoyl derivatives of maleamic acid and maleimide was prepared for hypocholesteremic and sulfhydryl-binding tests. The synthetic reactions involved in the controlled aminolysis of maleic anhydride with appropriate mono-substituted ureas and the resulting carbamoylmaleamic acids were then thermally dehydrated to the corresponding carbamoylmaleimides. The monosubstituted ureas required in this synthesis were obtained by the action of amines on isocyanic acid produced in situ from nitrourea on heating in aqueous alcoholic solution.
TL;DR: In this paper, a thermal transesterification of phenylurethane with n-octanol was carried out in DMSO and it was found that the reaction followed first order kinetics with an average rate constant of 8.630 × 10−5 sec −1 at 140°C.
Abstract: Thermal transesterification of phenylurethane with n-octanol was carried out in DMSO. It was found that the reaction followed first-order kinetics with an average rate constant of 8.630 × 10−5 sec −1at 140°C. High pressure liquid chromatograph technique was employed to analyze chemical species in the course of the reaction. The reaction obeyed Arrhenius equation closely between 133°C and 155°C with activation energy of 29.6 kcal/mole and entropy of activation of −8.2 cal/mole deg at 140°C. An intramolecular cyclic intermediate mechanism was proposed for this reaction.
TL;DR: In this article, a nmr spectroscopy-based reaction path was proposed for trimethylsilylation of naphthalene under certain conditions, and the possible reaction path has been determined.
Abstract: Direct trimethylsilylation of naphthalene under certain condition has been found to afford substitution as well as addition products: 1-and 2-trimethylsilylnaphtalene (I, II), 1-trimethylsilyl-1,4-dihydronaphthalene (III), trans-1,2-bis(trimethylsilyl)-1,2-dihydronaphthalene (IV-a) and its isomer (IV-b), and 1,2,4-tris(trimethylsilyl)-1,2-dihydronaphthalene (V). The configuration has been determined by nmr spectroscopy, and the possible reaction path was proposed.
TL;DR: In this article, the interaction between trans-1,2-diaminocyclohexane-N, N, N', N'-tetraacetic acid (H1DCTA or H4Z) and Mn(II) and Ni(II), has been investigated.
Abstract: The interaction between trans-1,2-diaminocyclohexane-N, N, N', N'-tetraacetic acid (H1DCTA or H4Z) and Mn(II) and Ni(II) ions has been investigated. The formation constants of the hydrogen chelates (MHZ−), and of the normal chelates (MZ2−), have been measured at 20, 30 and 40°C, and an ionic strength of 0.10 (KNO3). The former was done by a titration technique and the latter by a mercury indicator electrode method. Enthalpy and entropy changes characterizing the formation of the normal chelates have been calculated at 25°C.
TL;DR: In this paper, spiropentane was photolyzed using xenon 1470A resonance light source at room temperature and the photolysis products were analyzed by means of FID-gas-chromatographic technique.
Abstract: Spiropentane was photolyzed using xenon 1470A resonance light source at room temperature. The photolysis products were analyzed by means of FID-gas-chromatographic technique. Through the information about the yields of products, the major primary process of this light-molecule interaction was assigned as C-C bond breakage. Methylenecyclobutane, which has been an identified isomerization product of excited spiropentane molecule, was not able to be produced at present high excitation energy.
TL;DR: In this paper, the stationary phase of cation ion exchange resin was used for liquid chromatography of benzoic acid and phthalic acid, and aqueous ethanol was used as the mobile phase.
Abstract: This is to report a study in which cation ion-exchange resin serves as the stationary phase for liquid chromatography of benzoic acid and phthalic acid and aqueous ethanol acts as the mobile phase. No ion. exchange phenomenon is involved. It is rather a solvent action on the polymer matrix for the organic solutes. It was found that the elution volumes depend on the pKa values of the acids; the higher the pKa value the more the retention volume.
TL;DR: In this article, a polystyrenesulfonic acid resin in the hydrogen form is used for chromatographic separation of adenine, caffeine, theobromine, theophylline, tannic acid, xanthine and tea components with aqueous ethanol as eluent.
Abstract: A polystyrenesulfonic acid resin in the hydrogen form is a useful stationary phase for chromatographic separation of adenine, caffeine, theobromine, theophylline, tannic acid, xanthine and tea components with aqueous ethanol as eluent. The results indicated that caffeine, theophylline, theobromine, adenine, xanthine and tannic acid could be separated on a column of Dowex-50W-X8(H)+ by elution with 25% ethanol as eluent.
TL;DR: In studies of the phosphorylated proteins in Walker-256 carcinosarcoma, it was established that the ratio of P-N linkages to P-O linkages on histone H1 varied between 0.6 to 1.0.
Abstract: In studies of the phosphorylated proteins in Walker-256 carcinosarcoma, it was established that the ratio of P-N linkages to P-O linkages on histone H1 varied between 0.6 to 1.0. Histone H1 was phosphorylated in vivo and isolated under all neutral conditions employing a dextran/polyethylene glycol two-phase system and Bio-Rex 70 chromatography.