NMR Studies on the Subacute Biochemical Effects of Aristolochic Acid on Rat Serum

The subacute effect of aristolochic acid （AA） on rat serum was studied by NMR method. The biochemical effects induced by AA were characterized by an increase in the amounts of creatinine, trimethylamine N-oxide, acetoacetate, acetate and 3-D-hydroxybutyrate and lactate in serum from ^1H NMR spectra. Principal component analysis was used for further comparing the similarities of ^1H NMR spectral profiles of serum from rats treated with AA and model toxins.     

Study on the inclusion compound of β-cyclodextrin with (η5-cyclopentadienyl)tricarbonylmanganese(0)

The supramolecular inclusion compound of β-cyclodextrin (β-CD, host) with (η5-cyclopentadienyl)tricarbonylmanganese [MnCp(CO)3, guest] was obtained in a crystalline state. The host-guest compound is thermally stable and do not liberate the guest on heating at 100$ in vacuum. It was characteried by elemental analysis,1H NMR, differential scanning thermal (DSC) analysis and TLC. Continueous variation plot by NMR method shows that β-CD formed 1:1 inclusion compound with MnCp(CO)3. On the basis of 1H NMR spectra and the model building with Corey Pauling Koltum (CPK) models, the most probable inclusion mode is proposed.     

Structure of an Extracellular Polysaccharide from a Strain of Lactic Acid Bacteria

A new extracellular polysaccharide (EPS-I) isolated and purified from Z222, a strain of Lactic acid bacteria has been investigated. Sugar composition analysis, methylation analysis and ^1H NMR and ^13C NMR spectroscopy reveal that the EPS-I is composed of a pentasaccharide repeating unit. The sequence of sugar residue was determined by using two-dlmensional NMR spectroscopy, including heteronudear multiple-bond correlation(HMBC) and nuclear overhauser effect spectroscopy (NOESY).     

STUDY ON CASTOR OIL POLYURETHANE/POLY (METHYL METHACRYLATE) AB CROSSLINKED POLYMERS

Castor oil polyurethane/poly(methyl methacrylate) AB crosslinked polymers (ABCP) were synthesized by free radical copolymerization of MMA and vinyl-terminated castor oil polyurethane which was obtained from isocyanate-terminated castor oil polyurethane and hydroxyethyl methacrylate The mechanical properties, transition and relaxation, as well as compatibility and morphology of the ABCP were investigated by changing the component. The results show that the ABCP is a semicompatible system and the compatibility of the two components decreases with increasing content of the hard segment. The mechanical and damping properties of the ABCP are obviously superior to that of their homopolymers. The damping value is mainly controlled by cross[ink density of the ABCP but the T-g value by component.     

Structureal Study of Inclusion COmplex of Adrographolide with β-Cyclodextrin Prepared under Microwave Irradiation

An inclusion complex of β-cyclodextrin with andrographolide (Andro) was prepared by using a convenient method of microwave irradiation.The structure of the inclusion complex was determined by the ^1H NMR,2D NMR spectroscopy as well as the elemental analysis.     

THE ACTION MODE OF CISPLATIN ON DNA-SYNTHESIS AND CHARACTERIZATION OF N7 N1 CROSS-LINKAGE MODEL COMPOUND OF PLATINUM AND GUANOSINE

The title Pt-Guo compound was synthesized and isolated by the reaction between cis-[Pt(NH3)2(H2O)2](NO3)2 and guanosine of mol ratio1:1 in a neutral aqueous solution followed by careful purification with partial crystalization and recrystallizatlon from water at 0℃.The compound was characterized by elemental analysis,molecular weight determination,DTA,and C NMR spectroscopy and its formulawas found to be [8(GuoH-1)7 (OH)2] (NO3)7 8H2O.The isolation of the compound provides direct evidence for the intrastrand cross-linkage between cisplatin and DNA through N7,N1 atoms of two adjacent guanines.     

A New Enolate Furostanoside from Asparagus Filicinus

The roots of Asparagus filicinus Buch.-Ham are used to treat lung diseases such asbronchitis, pneumonities and cough in folk medicinel. Some steroidal glycosides havebeen isolated and characterized from the roots of this plant by several research groups'-'.In this paper, we report the isolation of a new unusual furostanol glycoside possessing anenolate moiety, whose strUcture was determined by I D and ZD NMR methods, FABMS,and hydrolysis. Bioassay results showed that the compound exhibit…     

Preparation and Cytotoxicity of Novel Aliphatic Polycarbonate Synthesized from Dihydroxyacetone

A new cyclic carbonate, 2,2-ethylenedioxypropane-l,3-diol carbonate (EOPDC), was synthesized through a two-step reaction from dihydroxyacetone dimer, and polymerized in bulk initiated by Sn(Oct)2 to give a high molecular weight polycarbonate. The structure of monomer and the polymer were characterized by FT-1R, ^1H NMR, ^13C NMR. The cytotoxicity of the obtained polycarbonate was investigated by MTT assay.     

双胍辛醋酸盐杀菌剂及其两种中间体的合成与生物活性

O-methylisourea acetate was synthesized by two procedures from the main raw materials including carbamide, dimethyl sulfate, acetic acid and concentrated sulfuric acid. Its content reaches 98 % and the total yield attains to 70%. 1, 17-Diamino-9-azaheptadecane was first synthesized by two procedures using sebcic acid, 1,8-octanediamine, sodium azide and concentrated sulfuric acid as the main raw materials. Its content reaches 98% and the total yield is 65%. The structure of both were confirmed by FT-IR, ^1H NMR and their available analysis method was established. Fungicide bis-(8-guanidino-octyl )amine acetate was synthesized from these two intermediates and its structure was confirmed by FT-IR and ^1HNMR. Fungicidal activity test showed that it is a kind of broad-spectrum fungicide with notably effect.     

Synthesis, Purification and Characterization of Amphiphilic and Microphase Separated Graft Copolymer Polystyrene-g-Poly(ethylene oxide)

The present paper covers the poly (ethylene oxide) macromer with vinyl benzyl terminal group (PEO-VB) prepared by deactivation of the alkoxide function of mono-functional "living" PEO chains with vinyl benzyl chloride (VBC). The obtained macromers were subjected to careful purification and detailed characterization. A new kind of amphiphilic polystyrene-g-poly(ethylene oxide) (PS-g-PEO) with both mi-crophase separated and PEO side chains was synthesized from radical copolymerization of PEO-VB macromer with styrene monomer. An improved purification method, referred as "selective dissolvation", was established for the isolation of graft copolymers from the grafting products, and the purity and yield of the purified copolymers were satisfactory. The well-defined structure of the purified copolymers was confirmed by IR, 1H NMR and GPC. The bulk composition of the graft copolymers was determined by a well-established first derivative UV spectrometry. Various experimental parameters controlling the copolymeri     

Effect of Specific Structure of Lotus Seed Oligosaccharides on the Production of Short-chain Fatty Acids by Bifidobacterium adolescentis

In order to study the structure of lotus(Nelumbo nucifera Gaertn) seed oligosaccharides and their effect on the proliferation of Bifidobacterium adolescentis, we extracted the oligosaccharides from seeds collected from Jianning County, China. We preliminarily characterized the groups, molecular weights, molecular formulae, component monosaccharides and glycosidic bonds using mass spectrometry(MS) and nuclear magnetic resonance(NMR) after isolation and purification. The lotus seed oligosaccharides contained glycosidic bonds Manp-(1→), Galp-(1→), α(1→6)-Glup and α(1→6)-Manp; and mannose was the chief component monosaccharide. NMR analyses showed that α-glycosidic bonds and pyranoid rings were predominant in the oligosaccharides. The MS analyses showed that lotus seed oligosaccharides consisted of three oligosaccharides of different polymerization degree, with relative molecular weights of 342, 504 and 666 Da, and corresponding molecular formulae C12H22O11, C18H32O16 and C24H42O21. Research on the effect of lotus seed oligosaccharides on the proliferation of B. adolescentis showed that they effectively promoted the production of acetic, propionic and butyric acids by B. adolescentis through fermentation, and their effect was stronger than that of fructo-, xylo- and isomalto-oligosaccharides. Lotus seed oligosaccharides have potential as a new functional probiotic and lotus seeds should be further explored and utilized as a source of oligosaccharides.     

Study on the Supramolecular Interaction of β-Cyclodextrin with Gemfibrozil by Spectrofluorimetry and Its Analytical Application

The supramolecular interaction of gemfibrozil with β-cyclodextrin （β-CD） was studied by spectrofluorimetry. The mechanism of the inclusion was discussed by spectrofluoremetry, infrared spectrum and ^1H NMR spectrum. The results showed that a 1 ： 1 （β-CD ： gemfibrozil） complex was formed with an apparent association constant of 3.844 × 10^3 L·mol^-1. Based on the enhancement of the fluorescent intensity of gemfibrozil, a spectrofluorimetric method for the determination of gemfibrozil in bulk aqueous solution in the presence of β-CD was developed. The linear range was 3.30 ng·mL^- 1 -6.00 ug·mL^-1 with the detection limit of 0.980 ng·mL^-1. There was no interference from the excipients normally used in tablet composition and the serum main compositions. The proposed method was then successfully applied to the determination of gemfibrozil in capsules and serum.     

Synthesis of 3-Benzyloxy-6-methyl-7-methoxyphenanthrene-9-carboxaldehyde with Utilize Intramolecular Heck Reaction as the Key Step

The substituted phenanthrene-9-carboxyaldehydes are very important intermediates for the syntheses of phenanthroindolizidine and phenanthroquinolizidine alkaloids. The novel title compound was prepared from the reaction of 5 steps starting from the condensation of 3-methoxyl-4-methyl-phenylacetic acid and 4-（benzyloxy）-2-iodobenzaldehyde, followed by esterification, cyclization, reduction, and oxidation. A new method for the preparation of phenanthrene ring via palladium-catalyzed intramolecular Heck reaction was described. The title compound was characterized by IR, ^1H NMR, ^13C NMR, elemental analysis, and MS.     

Studies on the Self-condensing Vinyl Polymerization of a Novel Maleimide Inimer

The self-condensing vinyl polymerization(SCVP) of a novel maleimide inimer(initiator-monomer) 1, N-(4-α-bromobutyryloxy phenyl) maleimide with the complex of CuBr/Bipy (2, 2‘-bipyridine) as the catalyst was studied. GPC was used to determine the molecular weight and the results show that the molecular weight increases exponentially with polymerization time during the first hour, and then the rate of increase molecular weight slows down. The molecular weight also increases with increasing dosage of the catalyst. The coincidence of the molecular weights determined by ^1H NMR and GPC proves that the polymer obtained from the SCVP of inimer 1 has a linear structure, whichis further verified by ^13C NMR spectrum. A hyperbranched polymer was obtained by the copolymerization of inimer 1 and styrene.     

Non-polar Solvent Microwave-Assisted Extraction of Volatile Constituents from Dried Zingiber Officinale Rosc.

A new method, non-polar solvent microwave-assisted extraction （NPSMAE）, was applied to the extraction of essential oil from Zingiber officinale Rosc. in closed-vessel system. By adding microwave absorption mediumcarbonyl iron powders （CIP） into extraction system, the essential oil was extracted by the non-polar solvent （ether） which can be heated by CIP. The constituents of essential oil obtained by NPSMAE were comparable with those obtained by hydrodistillation （HD） by GC-MS analysis, which indicates that NPSMAE is a feasible way to extract essential oil from dried plant materials. The NPSMAE took much less extraction time （5 min） than HD （180 min）, and its extraction efficiency was much higher than that of conventional polar solvent microwave-assisted extraction （PSMAE） and mixed solvent microwave-assisted extraction （MSMAE）. It can be a good alternative for the extraction of volatile constituents from dried plant samples.     

A Novel Dimeric Eremophilane from Ligularia virgaurea spp. oligocephala

A novel dimeric eremophilane, ligulolide B, was isolated from the alcoholic extract of the whole plant of Ligularia virgaurea spp. oligocephala. The structure was elucidated by various spectroscopic methods including intensive 2D NMR techniques （^1H-^1H COSY, gHMQC, gHMBC and ^1H-^1H NOESY） and HR-ESI-MS.     

A new isoflavonolignan from Pueraria alopecuroides Craib

A new isoflavonolignan has been isolated from the Pueraria alopecuroides Craib. The structure was elucidated by the combination of 1D, 2D NMR analysis and mass spectrometry.     

The structural analysis of the inclusion complex of β-cyclodextrin with m-nitrophenoxyacetic acid

The inclusion complex of β-cyclodextrin with m-nitrophenoxyacetic acid was studied by single crystal X-ray diffraction,2D NMR spectroscopy and semi-empirical methods AMI.The crystallographic study shows that two β-cyclodextrins are held together by hydrogen bonds to form head-to-head dimers.The disordered guest molecule adjusts itself to attain the most stable accommodation into the cavity in which the nitro group is located at the dimer interface while the carboxyl group is buried in the primary hydroxyl groups of β-cyclodextrin.The guest inside the cavity is disordered over two sites and exhibits mobility.Moreover,2D NMR spectroscopy and theoretical study show the same inclusion behavior.In comparison to the inclusion complex of β-cyclodextrin with p-nitrophenoxyacetic acid,the host-guest stoichiometries are different,i.e.,2:1 for m-nitrophenoxyacetic acid and 1:1 for p-nitrophenoxyacetic acid,while the inclusion orientation and the packing pattern of the host are similar in both complexes.     

Comparative Analysis of the Volatile Components in the Fresh Roots and Rhizomes of Curcuma wenyujin by Static Headspace Gas Chromatography Mass Spectrometry

Static headspace GC-MS method coupled with H/D exchange was firstly developed to determine and identifythe volatile components in the fresh root and rhizome of Curcuma wenyujin.The TIC chromatograms of 3 batchesof fresh roots harvested at different time showed significant difference in the volatile components:the constitutionwas the same but the content of them was different.More than 60 volatile components in fresh roots(Root of C.wenyujin)and rhizomes(Rhizome of C.wenyujin)of C.wenyujin were detected,of which 51 and 48 volatile com-ponents were identified respectively.The fresh roots and rhizomes of C.wenyujin were found to have the similarvolatile components.The contents of these components were calibrated by the response of β-elemene.In addition,the principal active component,β-elemene,was further confirmed and relatively quantified by its standard.γ-terpinene showed obvious allylic hydrogen/deuterium exchange using deuterium oxide which gave a new methodto identify some compounds containing allylic hydrogen.At the same time,the active hydrogen compounds werealso further confirmed.The results show that HS-GC-MS method is a fast,simple and efficient way for the analysisof volatile components from medical plants.     

Spectroscopic Study on Interaction of β-Cyclodextrin with Triprolidine Hydrochloride

The complexation of triprolidine hydrochloride （TRP） and β-cyclodextrin （β-CD） in deuterium oxide was investigated by 400 MHz 1^H NMR spectroscopy. The 800 MHz 2D ROESY data revealed that two 1 ：1 and one 2 ： 1 β-CD-TRP inclusion complexes were formed. Both aromatic moieties （p-tolyl and pyridyl ring） has entered into the β-CD cavity, confirming the existence of two different equilibria for 1 ： 1 inclusion complexes in which p-tolyl ring of the guest is more tightly held by the host cavity. The ROE intermolecular interactions provided the plausible structures of these 1 ： 1 and 2 ： 1 stoichiometric inclusion complexes of β-CD-triprolidine hydrochloride in solu- tion.