2000 Volume 11 Issue 3

The Sulfinatodehalogenation Reaction of α,α-Difluorobenzyl Halides with Sodium Dithionite
Jin Tao LIU , He Jun LU
2000, 11(3): 189-190
[Abstract](197) [FullText HTML] [PDF 80KB](0)
Abstract:
The sulfinatodehalogenation reaction of α,α-difluorobenzyl halides,ArCF2X (Ar=C6F5,C6H5; X=Br,I),with sodium dithionite took place readily in aqueous acetonitrile under mild conditions,giving the corresponding sodium sulfinate. The 1:1 adducts were obtained when alkenes were added to the reaction system in some cases.
Tetrahydrofuran Ring Opening with Acyl Chlorides or Anhydrides Catalyzed by Gallium Triiodides:A Novel and Facile Method for the Preparation of Iodo Esters
Hua Yue WU , Ren Er CHEN , Yong Min ZHANG
2000, 11(3): 191-194
[Abstract](197) [FullText HTML] [PDF 132KB](0)
Abstract:
Tetrahydrofuran ring can be opened with acyl chlorides or anhydrides catalyzed by gallium triiodides to afford iodo esters under mild conditions in good yields.
Synthesis of β-aminoesters and α-selenoesters via Active Metal Bismuth Produced by Sm/BiCl3 System in Aqueous Media
Yun Kui LIU , Yong Min ZHANG
2000, 11(3): 195-198
[Abstract](193) [FullText HTML] [PDF 111KB](1)
Abstract:
Active metal bismuth is produced in situ via Sm/BiCl3 system in aqueous media. Promoted by this active species,β-aminoesters and α-selenoesters are synthesized via reaction of α-bromoesters with 1-(a-aminoalkyl) benzotriazole and diselenides in moderate to good yields.
Et2AlCl-Mediated Reaction of α-4(20)-Epoxy-5α-hydroxy Taxinine B
Qian CHENG , Takayuki ORITANI , Tohru HORIGUCHI
2000, 11(3): 199-202
[Abstract](195) [FullText HTML] [PDF 185KB](0)
Abstract:
An α-4(20)-epoxy-5α-hydroxytaxinine B 1,when treated with diethylaluminum chloride,underwent reactions involving intramolecular substitution along with deacetylation or addition leading to new rings. Two novel 1-deoxy compounds 2 and 3 were isolated and fully characterized.
Novel Hydroperoxides of 1-Imino-3,3-Disubstituted-1,3-Dihydro Isobenzofuran
Wen Ge YAN , Bai Ling XU , Zong Ru GUO , Xiao Tian LIANG , Guang Zhong YANG
2000, 11(3): 203-206
[Abstract](206) [FullText HTML] [PDF 113KB](0)
Abstract:
Some 1-imino-3,3-disubstituted-1,3-dihydro isobenzofuran and 2-(1,1-disubstituted hydroxymethyl) benzamide derivatives have been obtained by the aminolysis of phthalide in the presence of triethylamine/aluminum chloride. 1-Benzylimino-3,3-disubstituted-1,3-dihydro isobenzofuran can be peroxidized to the corresponding hydroperoxides on exposure to the air for a long period. The structure was characterized by single crystal X-ray diffraction and the possible mechanism was suggested.
Synthesis of Pyrrole-Imidazole Polyamide
Jun Hua XIAO , Gu YUAN , Wei Qiang HUANG , Fei Li TANG , Albert S. C. CHAN , K. L. Daniel LEE
2000, 11(3): 207-208
[Abstract](202) [FullText HTML] [PDF 76KB](0)
Abstract:
One simple and versatile method is established for the synthesis of DNA recognition molecules-polyamides containing alternating N-methylpyrrole and N-methylimidazole without necessitating NH2- group protection.
An Improved and Efficient Preparation of the Chiral NAD(P)H Model (SS)-1-Benzyl-3-(p-tolylsulfinyl)-1,4-dihydropyridine
Jing LI , You Cheng LIU , Jin Gen DENG
2000, 11(3): 209-211
[Abstract](202) [FullText HTML] [PDF 127KB](0)
Abstract:
An improved procedure for the preparation of chiral NAD(P)H model,(SS)-1-benzyl-3-(p-tolylsulfinyl)-1,4-dihydropyridine,with satisfactary chemical yield and excellent enantiopurity is reported.
First Total Synthesis of Optically Active Oplopandiol Acetate, a Potent Antimycobacterial Polyyne Isolated from Oplopanax horridus
Liang XU , Xi Han WU , Guang Rong ZHENG , Jun Chao CAI
2000, 11(3): 213-216
[Abstract](188) [FullText HTML] [PDF 133KB](1)
Abstract:
The first stereoselective total synthesis of oplopandiol acetate 1,a potent antimyco-bacterial polyyne isolated from Oplopanax horridus,is presented. And its absolute configuration is confirmed to be (11S,16S).
An Improved Synthesis of the Natural Product Isorhapontigenin
Lian QIAN , Zhi Song PIAO , Lin WANG , Zhi Zhong ZHAO
2000, 11(3): 217-218
[Abstract](180) [FullText HTML] [PDF 63KB](0)
Abstract:
We have developed an alternative route to synthesize the natural product,isorhapotogenin. The synthetic product was characterized by IR and 1H-NMR in comparison with the corresponding natural product.
Electron Transfer Reaction between M-C6H6 and M+-C6H6 Complexes in the Gas Phase:Density Functional Theory Study
Ai Ping FU , Dong Mei DU , Zheng Yu ZHOU
2000, 11(3): 219-222
[Abstract](176) [FullText HTML] [PDF 186KB](0)
Abstract:
DFT/BLYP method is used to theoretically investigate the electron transfer (ET) reactions between M (Li,Na,Mg)-C6H6 and M+-C6H6 complexes in the gas phase. The geometry optimization of the precursor complexes and the transition state in the process of ET reaction was performed at 6-31G basis set level. The activation energy,the coupling matrix element and the rate constant of the ET reaction are calculated at semi-quantitative level.
Cobalt-catalyzed Photochemical Methoxycarbonylation of Olefins with Carbon Dioxide under Ambient Conditions
Jing Mei YIN , Ming GUO , Rui WANG , Guang Yun ZHOU , Da Bin GAO , Xiang Sheng WANG , Xin Wen GUO , Jian Qin ZHUANG
2000, 11(3): 223-224
[Abstract](169) [FullText HTML] [PDF 81KB](0)
Abstract:
The methoxycarbonylations of cyclohexene and 1-decene with CO2 can take place under ambient conditions by catalysis of[Co]([Co]=Co(acac)2,Co(OAc)2,CoCl2) in the presence of ultraviolet irradiation.
Two Novel Poly-Oxygen Bipyridine Alkaloids from Speranskia tuberculata
Jian Gong SHI , Han Qing Wang , Min WANG , Guang Xiong ZHOU , Yong Chun YANG , Wen Yan HU
2000, 11(3): 225-228
[Abstract](175) [FullText HTML] [PDF 116KB](0)
Abstract:
Two novel poly-oxygen bipyridine alkaloids,speranculatines A (1) and B (2) have been isolated from Speranskia tuberculata. Their structures were elucidated by spectroscopic methods including 2D NMR techniques and X-ray crystallographic analysis.
Abietane Quinones from Rabdosia serra
Xiao CHEN , Feng Jie DENG , Ren An LIAO , Qing Lan XIE , Xiao Hua XU
2000, 11(3): 229-230
[Abstract](177) [FullText HTML] [PDF 85KB](0)
Abstract:
A new abietane quinone diterpenoid was isolated,together with horminone,16-acetoxy-7-0-acetylhorminone,β-sitosterol,stigmasterol,ursolic acid and palmitic acid from the leaves of Rabdosia Serra (MAXIM) Hara. The new compound was elucidated as 16-acetoxy-7α-ethoxyroyleanone.
Two New Iridoid Glucosides from Clerodendrum serratum
Hui YANG , Bei JIANG , Zhi NA , Yun Pin GUO , Han Dong SUN
2000, 11(3): 231-234
[Abstract](168) [FullText HTML] [PDF 132KB](0)
Abstract:
Two new iridoid glucosides,serratoside A and serratoside B,were isolated from the aerial parts of Clerodendrum serratum var. amplexifolium Moldenke. Their structures were elucidated by spectral and chemical methods.
A New Taxane Diterpenoid from the Seeds of Taxus yunnanensis
Qing Wen SHI , Takayuki ORITANI , Ding ZHAO
2000, 11(3): 235-238
[Abstract](177) [FullText HTML] [PDF 132KB](0)
Abstract:
A new taxane diterpenoid with a rearranged 5/7/6-membered ring system was isolated from the seeds of the Chinese yew,Taxus yunnanensis. Its structure was established as 9α-acetoxy-5α-cinnamoyl-11(15→1)-abeotaxa-4(20),11-diene-10β,13α,15-triol on the basis of spectroscopic analysis. Its relative stereochemistry is proposed from the results of a NOESY experment.
Muricatenol, a Linear Acetogenin from Annona muricata (Annonaceae)
De Yu LI , Jing Guang YU , Xiu Zhen LUO , Lan SUN , Shi Lin YANG
2000, 11(3): 239-242
[Abstract](190) [FullText HTML] [PDF 102KB](1)
Abstract:
Muricatenol 1,a new acetogenin,has been isolated from the seeds of Annona muricata L.. Compound 1 is a C37 acetogenin without any THF rings,with four hydroxyls and one double bond in the long aliphatic chain. The hydroxyls of 1 are located at C-4,C-10,C-18 and C-19,respectively. The vicinal diol at C-18/C-19 is threo-configuration,and the double bond at C-14/C-15 is cis-configuration.
DSC Study on Brain Tubulin and the Effect of Cisplatin
Xiao Lei ZHOU , Yong YANG , Bao Huai WANG , Zhi Fen LI , Ai Xiao LIU , Lung Fei YEN
2000, 11(3): 243-246
[Abstract](183) [FullText HTML] [PDF 165KB](0)
Abstract:
The thermal property of the polymerization of brain tubulin was studied by a high-sensitivity differential scanning calorimeter. The phenomenon that heat flows increased and decreased consistently and obviously was observed. This phenomenon was called heat flow oscillation. It was probably correlated to the dynamic instability of microtubules. The effect of cisplatin on it was reported,too.
Interaction of Nicotine and Bovine Serum Albumin
Yan WANG , Yan CHENG , Hong Fang SUN
2000, 11(3): 247-250
[Abstract](180) [FullText HTML] [PDF 156KB](0)
Abstract:
The binding of nicotine to bovine serum albumin (BSA) was studied by UV absorption,fluorescence,and 1H NMR methods. With the addition of nicotine,the absorption band of BSA at about 210 nm decreased gradually,moved to longer wavelengths,and narrowed. BSA fluorescence of tryptophan residue was quenched by nicotine. The 1H NMR peaks of nicotine moved to downfield by the addition of BSA. The experimental results showed that nicotine was capable of binding with BSA to form a 1:1 complex. BSA's high selectivity for nicotine binding suggests a unique role for this protein in the detoxification and/or transport of nicotine.
The Photochemical Study of HSA and BSA with Resonance Light-Scattering and Fluorescence Spectra
Hong LIANG , Xing Can SHEN , Fang LI , Zhi Liang JIANG
2000, 11(3): 251-254
[Abstract](174) [FullText HTML] [PDF 165KB](0)
Abstract:
The resonance light-scattering (RLS) of human serum albumin (HSA) and bovine serum albumin (BSA) is reported for the first time,and applied to study photochemical reaction of HSA and BSA. The fact of photocrosslinking self-association effect in HSA and BSA solutions is identified by the enhancement of RLS. The fluorescence quenching at about 350 nm and 700 nm proves that tryptophan (Trp) residues are one of the photochemical activity sites in HSA and BSA molecules. The Rayleigh scattering (RS) spectra of HSA and BSA that were neglected in fluorescence spectra before are found at about 296 nm,592 nm and 888 nm for the first time,and are of adventageous to studying the aggregation of HSA or BSA. The possible photochemical reaction mechanism is also proposed.
Study on Fluorescence Property of Sparfloxacin Derivatizing System and its Application
Li Ming DU , Jing ZHOU , Qing Qin XU , Zhe Feng FAN , Rong YUAN
2000, 11(3): 255-258
[Abstract](168) [FullText HTML] [PDF 166KB](0)
Abstract:
In acid medium,sparfloxacin is oxidized by nitrous acid,then reacts with hydrobromic acid to form a new fluorescence substance,which can emit the strong fluorescence,which is 151 fold more than that of sparfloxacin itself. By this,a new sensitive method for the determination of sparfloxacin in human urine by derivative-synchronous fluorescence is presented with good results.
NMR Studies of 3-Acylcamphor
Zheng Ning LI , Xiu Mei LIU , Zhuo ZHENG , Hui Lin CHEN , Xiu Wen HAN
2000, 11(3): 259-260
[Abstract](175) [FullText HTML] [PDF 87KB](0)
Abstract:
NMR studies of some chiral 3-acyclcamphor were conducted. A complete assignment was given to 3-(4-pyridyl)carbonylcamphor by the 2D NMR technology. Assignments were also given to other β-diketones. The results showed that those 3-acylcamphors exist in the enol forms,while 2-benzoyl menthone exists in diketon form.
The Transient Time-Resolved Absorption Spectra of 1-Naphthylacetic Acid
Wen LI , Chen Ho TUNG , Jian Ping YE
2000, 11(3): 261-262
[Abstract](175) [FullText HTML] [PDF 60KB](0)
Abstract:
The transient absorption spectra of 1-naphthylacetic acid in tetrahydrofuran have been obtained by laser flash photolysis technique. The transient species bands are at 509.535 and 553 nm. These peak intensities increase in the maximum values at 10.4 μs.
Study on Speciation of Pr(Ⅲ) in Human Blood Plasma by Computer Simulation
Yan Min LIU , Jing Fen HAN , Zhi Jian WU , Yue WANG , Kui Yue YANG , Chun Ji NIU , Jia Zuan NI
2000, 11(3): 263-264
[Abstract](180) [FullText HTML] [PDF 82KB](0)
Abstract:
Speciation of Pr(Ⅲ) in human blood plasma has been investigated by computer simulation. The speciation and distribution of Pr(Ⅲ) has been obtained. It has been found that most of Pr(Ⅲ) is bound to phosphate and to form precipitate. The results obtained are in accord with experimental observations.
An Excellent Gas Chromatographic Stationary Phase for Separation of Phenol and Cresol Isomers——Heptakis(2,6-di-O-pentyl-3-O-allyl)-β-Cyclodextrin
Yue Qin ZHANG , Xue Yan SHI , Ruo Nong FU
2000, 11(3): 265-266
[Abstract](178) [FullText HTML] [PDF 68KB](0)
Abstract:
Heptakis(2,6-di-O-pentyl-3-O-allyl)-β-cyclodextrin as an excellent gas chromato-graphic stationary phase separating phenol and cresol isomers is described.
The lipase monolayer film self-assembly on the negatively charged poly(ethylene terephthalate) substrate
Xian Fu LIN , Lin HE , Li Heng XU , De Shui LU , Zhi Chun CHEN
2000, 11(3): 267-270
[Abstract](175) [FullText HTML] [PDF 195KB](0)
Abstract:
The PET-CO2- film was prepared and the lipase was assembled on the surface of the PET-CO2- substrate. The structure at the surface and activity of lipase/PET monolayer were studied by ATR-FTIR and AFM,and other methods.
The Structural Conversion in Microemulsion Systems of C12H25SO3Na-C4H9OH-C7C16-H2O
Chun Sheng MO
2000, 11(3): 271-274
[Abstract](188) [FullText HTML] [PDF 198KB](0)
Abstract:
An investigation of the structural conversion in microemulsion system of sodium dodecylsulfonate-butanol-heptane-water was carried out by cyclic voltammetry and conductivity techniques.
Adsorption and Reaction of CO on Mo(100)-c(2×2)-N Surface Studied by HREELS
Jun Fa ZHU , Jian Chang GUO , Run Sheng ZHAI , Xin He BAO , Shu Xian ZHUANG
2000, 11(3): 275-278
[Abstract](179) [FullText HTML] [PDF 204KB](0)
Abstract:
High resolution electron energy loss spectroscopy (HREELS) has been used to investigate the adsorption and reaction of CO on the Mo(100)-c(2×2)N surface. CO directly adsorbed on the N atoms from the c(2×2) layer to form isocyanate (NCO) surface species was found in addition to CO adsorbed on the molybdenum atoms at 120 K,indicating that both Mo and N atoms of the Mo(100)-c(2×2)-N surface are of high reactivities for CO adsorption.
Speciation of aluminum in acidic natural water equilibria with mineral phase kaolinite by chemical equilibrium calculation
Feng LIU , Shu Ping BI
2000, 11(3): 279-282
[Abstract](183) [FullText HTML] [PDF 210KB](0)
Abstract:
This paper presents a computer model using thermodynamic relationships and mass balance to investigate the speciation of aluminum in acidic natural water equilibria with mineral kaolinite. Factors affecting the distribution are discussed. Compared with the case of equilibria with gibbsite, some unique characteristics are discovered. The model is verified by analyzing practical water samples. Effect of errors in thermodynamic data on calculation is evaluated by the Monte Carlo simulation.
Address:Zhongguancun North First Street 2,100190 Beijing, PR China Tel: +86-010-82449177-888
Powered By info@rhhz.net