制备1—氰基—2,3,5—三—O—苯甲酰基—β—D—呋喃核糖的简便方法

制备１┐氰基┐２，３，５┐三┐Ｏ┐苯甲酰基┐β┐Ｄ┐呋喃核糖的简便方法张万轩＊雷策南黄锦霞陈家威（湖北大学化学系武汉４３００６２）关键词鸟苷，制备，氰基三苯甲酰基－β－Ｄ－呋喃核糖，三甲基氯硅烷１９９６－０８－１２收稿，１９９７－０３－０５修回１－氰...     

吡咯和呋喃气相质子化过程的密度泛函理论研究

Density functional theory and ab initio calculations have been used to determine structures and stabilities of the protonated aromatics species AH^＋ and AH2^2＋ （A=pyrrole, furan）. Possible mechanisms and relative energetics for protonation of pyrrole and furan by H3O^＋ and AH^＋ in the gas phase have been explored. Calculations show that the Cα-protonated species was the most stable structure for AH^＋, and the protonated AH^＋ might accommodate the second proton to yield AH2^2＋ if the free proton was available. The gas-phase H3O^＋ could protonate pyrrole and furan with significant exothermiCity and almost without barrier. The proton transfer from AH4^＋ to pyrrole and furan has a barrier ranging from 33.5 to 39.3 kJ/mol in the gas phase.     

葡萄糖、果糖和蔗糖在甲酰胺溶液中的体积性质

报导了含葡萄糖、果糖和蔗糖的甲酰胺溶液的密度数据，无限稀释表观摩尔体积和体积第二维里系数．利用改进的定标粒子理论、基团几何模型和基团加合方法，求解了溶质的空腔生成体积，溶质-溶剂间的氢键作用对体积性质的影响，并和水溶液中的情况进行了比较．     

稀土与含硫有机配体配合物的研究 Ⅳ.轻稀土元素与3-苯基-5-(呋喃-2)吡唑啉二硫代甲酸固体配合物的合成及性质

吡唑啉类化合物具有杀菌特性和植物生长调节作用,3-苯基-5-(呋喃-2)吡唑啉二硫代甲酸盐能与许多过渡金属离子形成稳定的配合物。而与稀土的配合物尚未报道。为考察稀土与含硫有机配体形成配合物的条件及该配合物的性质,我们在非水体系和保护气氛     

固相萃取高效液相色谱-质谱法测定动物组织中硝基呋喃代谢产物

研究了对动物组织中4种硝基呋喃类代谢产物AOZ、AMOZ、SEM和AHD的自动固相萃取HPLC-MS分析方法，分别以2-氯苯甲醛和2-硝基苯甲醛作为衍生化试剂，分别用AMOZ-d5、AOZ-d4作内标，用ENSPE柱进行提取，以乙腈-0．1％甲酸为流动相，采用梯度洗脱，可在15min内将4种代谢产物完全分离并进行测定。回收率为85％-90％；检出限可达0．5μg／kg。采用两种衍生化方法可获得较多的定性确证信息。采用本方法研究了硝基呋喃在鸡饲养过程中的残留规律。     

Two New Isobutyltartrate Monoester from Coeloglossum viride （L.） Hartm.var.bracteatum（Willd.） Richter

Two new isobutyltartrate monoesters,coelovirin A (1) and B(2),were isolated from the rhizomes of Coeloglossum viride (L.) Hartm. var. bracteatum (Willd.) Richter (Orchidaceae). Their structures were elucidated as (2R,3S)-2-isobutyltartrate-1-(4-β-D-glucopyranosyloxybenzyl) ester 1 and (2R,3S)-2-isobutyltartrate-4-(4-β-D-glucopranosyloxybenzyl) ester 2 on the basis of physical constants and spectroscopic methods including 2D NMR techniques.     

A Novel Asymmetric Synthesis of （-）-cis-1, 3-Dibenzylhexahydrofuro[3, 4-d]imidazole-2,4-dione

(-)-cis-1, 3-Dibenzyl-hexahydrofuro[3, 4-d]imidazole-2, 4-dione was prepared by a new synthesis method from meso dicarboxylic acid and dehydroabietylamine by asymmetric reduction in good yield with up to 91.6% e.e. value.     

呋喃同系物C4H4X(X=O,S,Se,Te)非线性光学性质的TDDFT-SOS理论研究

用含时密度泛函理论(TD-DFT)组合态求和(SOS)方法计算了呋喃同系物[呋喃(C4H4O)、噻吩(C4H4S)、硒吩(C4H4Se)、碲吩(C4H4Te)]的非线性光学性质.计算结果表明,体系的三阶NLO系数(γ)随着杂原子被重原子的取代而逐步增大,B3LYP等4种势函数计算的NLO系数基本一致.计算的色散关系曲线表明,标题化合物在宽频区存在小的色散作用,是一类具有应用前景的NLO材料.     

Synthesis of Novel Nucleoside Analog （3R）-2,3-Dideoxy-3-（N-hydroxy-N-methylamino）-L-arabinofuranosyl Uracil

The synthesis of novel nucleoside analog (3R)-2,3-dideoxy-3-(N-hydroxy-N-methylamino)-L-arabinofuranosyl uracil was studied. A twelve-step synthetic route, started from L-ascorbic acid, was designed, and the final product was obtained in 20.8% yield.