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    24 June 1984, Volume 5 Issue 3
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    Articles
    STUDIES ON THE LANTHANIDE COMPLEXES WITH 18-MEMBERED HEXAAZA MACROCYCLIC LIGANDS
    Wang Genglin, Miao Lan
    1984, 5(3):  281-286. 
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    Fifteen lanthanide, including Eu (Ⅱ), complexes of 18-membered hexaaza macrocyclic ligands and one free macrocyclic compound have been prepared by template reactions. Their compositions and structures were ascertained by elemental analyses, infrared spectra, electrical conductance measurements and DTA-TG analyses. The stability of these solid complexes and their characters in aqueous solution have been studied as well. The results indicated that the complexations of lanthanide ions with 18-membered hexaaza macrocyclic ligands are very stable, but the replacement of the ligands other than macrocycle is taken place easily.
    STUDIES ON PREPARATION AND CHARACTERIZATION OF COMPLEXES OF RARE EARTHS WITH TOLBUTAMIDE
    Zhu Yiqing, Wu Jigui, Deng Ruwen
    1984, 5(3):  287-302. 
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    In this work we have reported the method of preparation of fifteen rare earth complexes with tolbutamide (D860). The composition of the complexes has been determined by chemical analysis. Their physico-chemical property, X-ray powder diffraction, IRabsorption spectra and NMRhave been investigated. The thermal stability of the complexes has been discussed.
    THE EXTRACTION MECHANISMS OF Au AND Pt BY PROPYLENE CARBONATE AND THE PROCESS OF BACK-EXTRACTION
    Wang Naidong, Sun lie, Lin Feng
    1984, 5(3):  303-307. 
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    The effects of impurity ions on the extraction of gold and platinum in the propylene carbonate (PC)-chloroform system and the selection of back-extration condition have been investigated. The extraction mechanisms of gold and platinum were discussed with the slope method, the saturated method, chemical analysis, UV-spectrum and IR-spectrum.
    INFLUENCE OF HEATED TUBE MATERIAL IN A CONSTANT-TEMPERATURE FURNACE ATOMICABSORPTION SPECTROSCOPY
    Zheng Yansheng
    1984, 5(3):  308-310. 
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    In the paper the atomization behaviours of Al, K, Ag and Cd in the ordinary graphite and the glassy carbon tube are studied. The experiment showed that the slopes of calibration curves established for Al, K, Ag and Cd in the glassy carbon tube are larger than those in the graphite tube.Therefore, the analytical sensitivities of the elements are increased by using the glassy carbon as heated tube. The influence of the heated tube material on the shape of the absorption charateristic curve and on trailing phenomena of the signals, occured in the glassy carbon and the graphite tube, are related to the nature of elements. The trailing of signal for Ag and Cd did not appear in two heated tube, But the trailing of the signal for Al and Ktaked place in two heated tubes.
    THE COORDINATION REACTION OF SOME BISAZO DERIVATIVES OF CHROMOTROPIC ACID WITH RARE EARTH ELEMENTS(Ⅱ)——THE DISCUSSION ON THE RELATION BETWEEN THE AUXOCHROMES SOLVENTS AND α-TYPE β-TYPE REACTION
    Ni Zhaoai, Ma Yongfu
    1984, 5(3):  311-314. 
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    The relation between the auxochromes, solvents and a-type, β-type reaction was investigated in this paper. It shows that only the bisazo derivaties of chromotropic acid containing stronger electrophilic auxochromes such as -Cl, -NO2, -COCH3, -COOH can form β-type chelates with rare earth elements, and the auxochromes of -SO3H, -PO3H,-AsO3H2 only form in a-type.This paper points out that under proper conditions the bisazo derivatives which form β-type chelates can be extracted by isoamyl alcohol, but not the a-type.The formation of β-type chelates can be inhibited by some solvents such as ethyl alcohol and acetone. But these solvents can greatly raise the sensitivity of the a-type reaction.
    SPECTROPHOTOMETRIC-COMPLEXOMETRIC TITRATIONS (Ⅱ)——THE TITRATION OF MICRO-QUANTITIES OF ALUMINIUM-MALONIC ACID AS MASKING AGENT
    Chen Yongzhao, Zhang Zhenhua, Chen Huanguang
    1984, 5(3):  315-320. 
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    We found that malonic acid is a specific masking agent for Al in complexometric titration, and by using the DCTA-malonic acid masking method, Al can be indirectly titrated. This paper reports that 3-100μg of Al (in 35 ml) can be accurately spectro-photometrically titrated with this method at pH 5.5 without the interference of the following metal ions: Zr, Th, Sn, Bi, Fe, Ti, Ga, Ce, La, Y, Gd, Cr, Hg, Cu, Ni, Co, Pb, Zn, Cd, Mn, V, Sb, Mo, W, Ca, Mg, etc. The selectivity of the titration is very high. When the Al is titrated at pH 3.5 less metal ions will not interfere, but it allows larger amount of Ca and Mg present.This method was successfully used to determine the microquantities of Al in limestone, dolomite, quartz and tap-waters.
    AN APPLICATION OF COMPUTERS IN ANALYTICAL CHEMISTRY——THE CALCULATION OF THE pH OF THE PRECIPITATION ON SPARINGLY SOLUTION COMPOUNDS IN THE PRESENCE OF MASKING AGENTS
    Zhang Sunwei, Pan Fuyou, Yao Jian, Kong Fangming
    1984, 5(3):  321-326. 
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    In the complex system existing masking agents, others presented the theoretical possibility of calculation the pHof the forming cnoditions of sparingly solution compound, but it is difficult to find a solution of the equation after the values of all the parameters are substituted,especially by mannual calculation if high order equations are involved.In this paper, application of computer can solve a number of complicated problems like the aforesaid. For this purpose we adopted BASIClanguage which did not demand operation and drawing up programs from this, we arranged commonly used program and calculated the pHand obtained results consistent with experimental values.
    THE EFFECT OF NONIONIC SURFACTANTS ON THE MICELLAR SOLUBILIZATION SPECTROPHOTOMETRY (Ⅱ)
    Zheng Yongxi, Wang Zhendi
    1984, 5(3):  327-332. 
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    In acidic medium the intcrreaction of basic dye cations and (or) ion-assoication complexes with r.onionic surfactants (such as Emulsifying agent OP) has been studied. On the basis of comparis on and analysis of corresponding spectra the effect of nonionic surfactants on the micellar solubilization spectrophotometry is described as "PseudohomogeneousExtraction Model" ——the ion-association complexes do not react withthe individual molecules of nonionic surfactants or the micelle, they are only solubilized in the polyethoxy group of nonionic surfactants micelle. This conclusion has been further confirmed by phase separation experiments at the cloud point and by organic solvent extraction.The effect of hydrogen ion concentration [H+] on the decolourizing rate and protonation of basic dye, on the equilibrium and sensitivity of the ion-association complexes has also been discussed. In the presence of nonionic surfactants the reagent blank shows a light-green colour which has λmax =620nm,but the absorbance maxima of the ion-association complexes (CV-PMo and CV-AsMo) which show a dark-blue colour, are all located at 545nm.The method has been used for the spectrophotometric determination of Pand As in the steel.
    THE SYNTHESIS OF CROWN ETHERS(Ⅵ)-——STUDY ON THE SYNTHESIS OF UNSYMMETRIC SATURATED URASHIOL CROWN ETHERS BY THE METHOD OF PHASE TRANSFER CATALYSIS
    Shu Jiayou, Zhang Zhengan, Huang Zaifu
    1984, 5(3):  333-338. 
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    Anumber of new unsymmetric saturated urashiol crown ethers are synthesized by the method of phase transfer catalysis.The reaction takes place in the presence of sodium hydroxids solution containing an optimun quantity of about 0.4 molar of the a: imonium salt.The bis(chloroalkoxy)-dcrivatives, the intermediates needed in the synthesis, are prepared in good yields from catechol, resorcin, hydroquinone and saturated urachiol by the same method.The catalysts which gave good results are tetrabutylammonium hydrogen sulfate, hexadeyltrimethylammonium hydrogen sulfate etc..
    Preface
    SYNTHESIS AND REACTION OF BIS(CYCLOPENTENYLCYCLOPENTADIENYL) Ⅳ B GROUP METAL DERIVATIVES
    Chen Shoushan, Wei Rongbao, Wang Jitao
    1984, 5(3):  339-344. 
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    Bis (cyclopentenylcyclopentadienyl) metal dihalides, (RC5H4)3MX3 (M=Ti,Zr,Hf,R= <这里有图片19840310-339-1.gif> X=F,Cl,Br) and diaryl, disulfocyanide, dihydrosulfide derivatives have been synthesized. The double bond of cyclopentenyl on Cp with HBr, halogen underwent normal electrophilic addition reaction. The 1H NMRspectra of aformentioned derivatives are discussed.
    Articles
    STUDY ON HIGH-TEMPERATURE LIQUID CRYSTALS AS STATIONARY PHASES FOR GAS-LIQUID CHROMATOGRAPHY(Ⅰ)——SEPARATION OF PHENANTHRENE, ANTHRACENE AND CARBAZOLE USING BIPHENYLENE BIS-(p-n-ALKOXYBENZOATE) LIQUID CRYSTALS AS STATIONARY PHASES
    Fu Ruonong. Wu Wenhui, Li Guozhen
    1984, 5(3):  345-349. 
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    The high-temperature liquid crystals p-biphenylene bis-(p-n-alkoxy-benzoate) homologs, in which alkyl group is propyl, butyl, amyl, hexyl, heptyl and nonyl, have been used as stationary phases for gas-liquid chromatographic separation of ph'enanthrene, anthracene and car-bazole. For comparsion some conventional liquid phases such as OV-101, OV-25, OV-210, OV-225 and Versamide-930 were studied as well.To find some better liquid phases relative retention was determined on 0.5m columns packed with these stationary phases. It is found that BPBBB (with Butyl group) and BPBAmB (with Amyl group) are better to separate the mixture of phenanthrene, anthracene and carbazole. On a 0.5m column packed with the liquid crystal BPBAmBon Chromosorb W NAW, the mixture can be separated satisfactorily within 16 minutes.
    SYNTHESIS OF 4-FLUORO-1,2-DIHYDRO-3,6- PYRIDAZINDIONE AND ITS DERIVATIVES
    Tian Guanrong, Lin chengji
    1984, 5(3):  350-354. 
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    4-Fluoro-1,2-dihydro-3,6-pyridazindione( Ⅱ ) and 1-phenyl-3-hydro-xy-4-fluOro-6-pyridazinone (Ⅶ) were prepared by reaction of fluoro maleic anhydride with hydrazine hydrate and phenyl hydrazine, respectively. (Ⅱ) reacted with phosphorus oxychloride to afford 3,6-dichloro-4-fluoro-pyridazine( Ⅲ ). ( Ⅲ ) reacted with sodium methoxide, in equal molar ratio, to give 3-methoxy-4-fluoro-6-chloro-pyridazine (Ⅳ), while in 1 to 3 ratios, to give 3,4-dimethoxy-6-chloro-pyridazine (Ⅴ). (Ⅲ) reacted with sodium o-metnyl-phenoxide, to give 3-o-methyl-phenoxy-4-fluoro-6-chloro-pyridazine(Ⅵ). In(Ⅲ), nucleophilic displacement is taken place preferably at 3th position. (Ⅱ), (Ⅲ), (Ⅳ), (Ⅵ) and (Ⅶ) are new compounds. (Ⅱ) has a plant growth regulator property and (Ⅶ) has an anticonvulsemt effect.
    THE FATTY ACIDS, STEROLS AND TRITERPENE ALCOHOLS IN SEED OIL OF CAMELLIA WEININGENSIS
    Yan Meihe, Li He
    1984, 5(3):  355-360. 
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    The study of the fatty acids contents in Camellia weiningensis Li sp. nov (Theaceae) seed oil was carried out by using two analytical methods.The unsaponifiables of this oil were separated by silica gel column chromatography into four fractions. The present paper deals with the composition of triterpene alcohols, 4-methylsterols and sterols. All these fractions were analysed by TLCand GLCtheir major mponents were identified by melting point determination, optical rotation, GLC, TLC, IRand MSa-Spinasterol, △7-stigmastenol, β-amyrin, germanicol, ψ-taraxasterol, tirucalladienol,butyrospermol and dammaradienol were isolated and identified. 7-Avenasterol, a-amyrin, citrostadienol and cycloeucalenol were identified. Trace quantities of △5-sterols were also separated by designed TLCon silica gel and cholesterol, campesterol, stigmasterol and β-sitosterol were identified.No evidence of nonedibles was found in this oil.
    SYNTHESIS OF SOME 1-ACYL BENZIMIDAZOLE AND 1-ACYL IMIDAZOLE DERIVATIVES
    Chen Ruyu, Liu Tianlin, Zuo Xiangrikui
    1984, 5(3):  361-365. 
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    24 new l-acyl-2-phenoxymethyl benzimidazoles and derivatives of 1-phenoxyacetyl imidazole have been prepared by the reaction of 2-sub-stituted benzimidazoles or imidazole with acyl chloride in the presence of organic bases such as trithylamine, pyridine or imidazole itself. The derivatives 1-phenoxyacetyl imidazole were readily converted into their imidazole salts when they were exposed to the air.It has been shown that some of them enhance or inhibit the growth of wheat from the results of wheat coleoptile segment test.
    STORK ACYLATION WITH N-METHYLPIPERAZINE AS THE AMINE COMPONENT IN THE FORMATION OF ENAMINES
    Li Liangzhu, Su Ruilan
    1984, 5(3):  366-368. 
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    Instead of usual cyclic secondary amines such as morph'oline etc., the N-metlylpiperazine was used in the Stork enamine acylation reactions and the following facts were found:1.The external neutralizer, such as TEA, used in usual procedure cannot be added now because a tertiary amine group is present in the N-methylpiperazine ring, but the yields of acylated enamines are less than that where TEAis added.2. The isolation of acylated enamine hydrochlorides is still difficul't for these hydrochlorides are h'ydroscopic and decompose readily on standing.3. In acylation reactions the diacylated products are also formed.
    THE TRANSITION STATE THEORY OF CHEMICAL REACTION RATE
    Deng Conghao
    1984, 5(3):  369-374. 
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    The elementary chemical reactions are assumed to pass via the transition states. From the Hersenberg equation of motion, it is proved that the probabilities of transition states are stationary. From this theorem and the Hersenberg equation of motion there are derived the micro and macro reaction rate constants of both the direct and complex models of reactions.
    HETERO-ATOM ZEOLITE(Ⅱ)-STUDIES ON THE CRYSTAL STRUCTURES OF B-Si PENTASIL ZEOLITE MOLECULAR SIEVES
    Pang Wenqin, Li Guowen, Li Wangrong, Zhang Wanjing, Lin Bingxiong
    1984, 5(3):  375-380. 
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    The crystal structure of B-Si pentasil zeolite molecular sieves has been determined by means of the X-ray diffraction for polycrystalline materials and has been refined with Rietvelds method. The parameters ofthe cell are : a= 19.983(1)Å; b= 19.973(1) Å; c= 13.303(1)Å. Its space group is D2h16-Pnma, The framework topology found agrees with reported Si-Al ZSM-5 zeolite molecular sieves. It is concluded from the structure detemination that Bis introduced into the framework of this sample.
    DISCUSSION ON THE ELECTROKINETIC EFFECTS BY WAY OF NONLINEAR NON-EQUILIBRIUM THERMODYNAMICS
    Kang Chenghua
    1984, 5(3):  381-384. 
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    This paper discusses the electrokinetic effects by way of nonlinear non-equilibrium thermodynamics. First, it explains the inconsistency of the experimental values with the old theory. Second, the paper introduces the approximate conditions, under which the old theory is used to deal with the electrokinetic effects. Last, a new idea is put forward that under certain conditions, so far as some liquid and membrane are concerned, the electrokinetic effects might appear to be of the dissipative structures when △P and △φ reach a certain value.
    THE POLYCZNTRAL GTO BASIS SET FOR AB INITIO CALCULATION
    Peng Zhouren, Du Qishi
    1984, 5(3):  385-388. 
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    In the present investigation the polycentral GTObasis set for ab initio LCAO-MO-SCFcalculation is given. The ab initio FORTRAN Ⅳ general program ABHFusing this basis set is written by us. The calculations of the energy, dipole moment, virial value, especially the Hell-mann-Feynman force obtained from this basis set are better than the ones obtained from the previous STO-GTObasis sets. This basis set is particularly appropriate for calculation of the polarized molecules. Tt provides a way of study of the chemistry by means of the force.
    IRREDUCIBLE TENSOR OPERATOR METHOD FOR CALCULATING ENERGY SPECTRUM OF TRANSITION- METAL IONS IN CRYSTALS
    Ma Dongping, Xu Yisun, Hu Zhixiong
    1984, 5(3):  389-394. 
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    We have analysed the formulas of generalized Wigner-Eckart theorems in reference〔10〕 and the characteristics of the wave functions of mixed states due to mixing of aLby Vc. Four corollaries and the results associated with the corollaries are derived. The calculation of matrix elements in the mixed states,is reduced to a simple calculation of matrix elements in the unmixed states, or the calculation of all non-zero matrix elements between two octahedral field terms is reduced to a simple calculation of a matrix elements in mixed states.By using this method, these problems involved energy spectrum of dn ions in a trigonally or tetragonally distorted octahedral crystal field can be overall dealt with in detail.
    THALLIUM-205 NUCLEAR MAGNETIC RESONANCE STUDY OF THALLIUM COMPLEX WITH 18-CROWN-6 IN AQUEOUS SOLUTION
    Pan Guihuang
    1984, 5(3):  395-397. 
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    The thermodynamics parameters for the reaction of 18-crown-6 with Tl( I ) in water were determined by using NMR. The stability constant, enthalpy, entropy, and free energy were calculated to be lgK = 2.11 ±0.02, AH = -4.49±0.17 kcal/mol, △S = -5.35 ±0.54 cal/mol and △G0=-2.88 kcal/mol at 25.1℃, respectively. These values were in good agreement with values reported in the literature.
    SYSTEMATIC CHECK OF SYMMETRY GROUP TABLES (CONTINUED)——PROOF ON THE ERROR OF THE GENERAL FORMULA B OF THE SPACE GROUP P42/nnm
    Jin Songchun, Jin Zhongsheng, Liu Yongsheng, Guo Dongyao
    1984, 5(3):  398-400. 
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    Amistake in the expression of the structure factor for the space group P42/nnm (No. 134, Origin at 42m) was found and corrected by the use of the theorems of the structure factor type.
    CORRELATION BETWEEN ACIDITY AND ACTIVITY OF RARE-EARTH EXCHANGED Y ZEOLITE CRACKING CATALYSTS AND OTHER SOLID ACIDS
    Li Rongsheng, Zhang Wuyang, Song Ruifang
    1984, 5(3):  401-403. 
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    Taking cracking of cumene as the model reaction and using Hammett indicator method, high temperature ammonia adsorption method and ESRtechnique, we have studied primitively the correlation between activity, coking and acidity of 4 rare-earth exchanged Yzeolite cracking catalysts and other solid acids.From our results can be seen:1. More active sites of catalysts are favorable to coking, leading their faster deactivation.2. For cracking of cumene at 250℃ the active sites which make contribution to cracking activity seem to be.Sites whose range of strength is H0≤5.6, according to Hammett indicator method;Sites whose range of desorption temperature is T>250℃, according to high temperature ammonia adsorption method.
    TRANSPORT OF SOME CATIONS ACROSS THE LIQUID MEMBRANE BY CROWN COMPOUNDS
    Zhu Jiaqin, Yang Yansheng
    1984, 5(3):  404-406. 
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    Transport rates of La3+,Fe3+,Ca3+,Na+ ions,as well as the amount and selectivity ratio of transport for La3+ , Sm3+ , and Er3+ ions across the liquid membrane by DB-18-C-6 and B-15C-5 were determined.It was found that from a chloride solution the transport rates for Ca2+ , La3+ , Fe3+ and Na+ ions are very small. For DB-18-C-6 as carrier, during 12 hrs., the amount of La3+ and Na+ ions transported are 49.7% and 54% respectively, and the selectivity ratio for Na+/La3+ is about 1.08. For B-15-C-5 as carrier the amount of La3+ and Na+ ions are 47.5% and 54.0% respectively, and the selectivity ratio for Na+/La3+ is about 1.13.While for picrate solution the amount of La3+ , Sm3+ and Er3+ions transported are 24.1%, 46.0% and 14% respectively, and the selectivity ratio for Sm3+/Er3+ , Sm3+/La3+ and La3+/Er3+ are 3.28, 1.91 and 1.72 respectively.
    MOSSBAUER STUDY OF THE CORROSION PRODUCTS OF BOILER TUBES
    Hong Ruiyu, Lin Xuehao
    1984, 5(3):  407-409. 
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    The corrosion products of boiler tubes, economizer and superheater were studied by Mossbauer spectroscopy. It was found that the a-Fe2O3 content in the corrosion products increased, but the Fe3O4 content decreased, with increase of corrosion time. The corrosion process of boiler tubes should be. formation of Fe3O4 first, and further oxidation of Fe3O4 to a-Fe2O3 . It was also found that IB/IA was<<2 in Fe3O4. This phenomenon was probably caused by incorporating some other ions into Fe3O4. The results were complemented by X-ray diffraction, infrared spectra, chemical analysis and electron probe analysis.
    STUDIES ON NEW TYPE CARBON-CARBON BOND INITIATORS
    Liu Youcheng, Yang Dilun, Lu Huilin
    1984, 5(3):  410-414. 
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    Diethyl 2,3-dicyano-2, 3-diphenylsuccinate (I) was synthesized by oxidative coupling" reaction of ethyl a-cyanophenylacetate with Cu++-TMEDA-O2 system. The structure of Iis determined on the basis of IR, 1HNMR, UV, MSand elemental analysis, and through alkaline hydrolysis of Ito 2,3-diphenylsuccinonitrite. The configuration of Iis identified to be the meso-isomer by x-ray crystallographic analysis in collaboration with the Institute of Physical Chemistry of Beijing University. The conversion-time curves are determined when Iwas used as initiator in the bulk polymerization of styrene at 80, 90,100, 110 and 120℃ respectively. Mw, Mn and dispersion coefficients of polymers obtained with a fixed amount of Ias initiator in the bulk polymerization of styrene at 70, 80, 90, 100, 110, 120 and 150℃ or with various amounts of Ias initiator at 100℃ are determined by GPC. The results show that Iis a safe and efficient carbon-carbon bond initiator.
    Preface
    A KINETIC STUDY OF ALTERNATING COPOLYMERIZATION OF BUTADIENE AND PROPYLENE BASED ON VANADIUM-ALUMINIUM CATALYST (Ⅱ) ——DETERMINATION OF KINETIC PARAMETERS AND EQUATION FOR AVERAGE DEGREE OF POLYMERIZATION
    Jiao Shuke, Huang Baochen, Qi Yincheng
    1984, 5(3):  415-420. 
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    Initiation, propagation and chain transfer process of B-Palternating copolymerization were studied. We used the extrapolation to get the active center concentration and various kinetic parameters such as kp , k11, Ep and Etr etc. We also distingushed two kinds of chain transfer processes i.e. monomer transfer and β-Htransfer and their relative contribution. According to the experimental data the equation for the average degree of polymerization may be expressed as  Finally, the average life time t of living polymer chain was obtained. Using different methods, the accuracy of those methods was discussed.
    Articles
    A STUDY OF THE CURING KINETICS OF EPOXY RESINS BY SPLINE SIMULATION FUNCTION
    Huang Jifu, Wang Ueren, Zhang Baolong, Lu Yanling, Hu Xiangwei, Chen Guohua, Yang Biao, Liu Zhixin
    1984, 5(3):  421-426. 
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    Spline simulation function has been applied to the study of the curing kinetics of epoxy resins and better accuracy of DSC simulated curves and more satisfactory kinetic parameters were obtained. The values of apparent activation energies, E, obtained from the isothermal curves were in the range of 10-12 kcal/mol, which agreed with the results of our previous TBAexperiment as well as those reported in the literature. Similar results (apparent activation energy Eand reaction order n) were observed from the dynamic DSCexperimental curves of the reaction systems.
    THE MOLECULAR WEIGHT AND SEGMENT DISTRIBUTIONS OF BINARY COPOLYMERS(Ⅰ)——LIVING COPOLYMERIZATION
    Yang Meilin, Shen Jiacong, Tang Aoqing
    1984, 5(3):  427-431. 
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    Polydimcnsional Poisson's distribution function, which can characterize both molecular weight and arbitrary length segment distributions of the binary living copolymers, has been first derived by the method of combining probability with kinetics. It can be transformed into poly-dimensional Gaussian distribution for simplifying calculation. Aformula for calculating the theoretical GPCchromatogram of the product in the living binary copolymerization has also been obtained by using this distribution function and the additivity of hydrodynamic volumes
    A QUANTUM BIOCHEMICAL APPROACH TO THE INTERACTIONS OF CYCLIC AMP AND GMP WITH PROTEIN KINASE (Ⅱ) ——THE ELECTRONIC STRUCTURES OF 5'-CH2-cAMP AND cGMP
    Wang Zhizhong, Guo Chunxiao, Zhang Xuezhong, Cheng Yuhua
    1984, 5(3):  432-436. 
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    In this paper we have calculated the electronic structures of the cyclic nucleotides cAMPand cGMPby means of the CNDO/2 method. On basis of the computed charge distributions in the molecules the possible interaction mechanism between the mentioned nucleotides and protein kinase has been discussed. We have showed that in this interactions the essential part perhaps is the sugar-cyclic phosphate one, and it includes electrostatic interactions of both 3' and 5' and exocyclic oxygen atoms and also the hydrogen bond interactions of oxygen atoms O3', O5' and O2'. At the same time, we have also discussed the possible actions of bases in regulating activity of two cyclic nucleotides. In addition we have analyzed some hydrogen bonding in both nucleotides cyclic cAMP and cGMP.
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