SU(2)规范场分解与Bose-Einstein凝聚体中的环流条件

利用SU(2)规范场的单位矢量场分解形式讨论了Bose-Einstein凝聚体中的环流条件.对于二分量Bose-Einstein凝聚,内部态的SU(2)对称性将导致一个拓扑环流条件,这是一个推广的Mer-min—Ho关系.     

Poly（ethylene glycol）-supported Liquid-phase Parallel Synthesis of Di（aryloxyacetyl）thiosemicarbazides

An efficient poly(ethylene glycol) (PEG)-supported liquid-phase parallel approach to di(aryloxyacetyl)thiosemicarbazides is described. PEG-bound phenol reacted with chloroacetic acid to afford PEG-bound phenyloxyacetic acid, which was readily converted into corresponding phenyloxyacetyl chloride. Subsequent nucleophilic substitution with ammonium thiocyanate followed by addition of aryloxyacetic acid hydrazides gave PEG-bound di(aryloxyacetyl)thiosemicarbazides, which were easily cleaved to give the resulting library of 1-aryloxyacetyl-4-(4‘-methoxylcarbonylphenyloxyacetyl)thiosemicarbazides in good to high yield and high purity.     

A New Stigmasterol and a New Eremophilenolide from Ligularia dolichobotrys

A new stigmasterol 3β, 7α, 22-trihydoxystigmast-5-ene (1) and a new eremophilenolide 8α-methoxy-6β-angeloyloxyeremophil-7(1 l)-en-8β, 12-olide-14-oic acid (2) were isolated from Ligularia dolichobotrys Diels. Their structures were deduced on the basis of spectral data.     

The First Total Synthesis of Natural 6β-Cinnamoyloxy-1α- hydroxy-5, 10-bis-epi-eudesm-4-en-3-one

Eudesmane and agarofuran are naturally occurring sesquiterpenoids with characteristic decalin skeletons. These natural products frequently contain multiple hydroxyl groups and contiguous stereocenters. Members from these families show cytotoxic, immuno- s…     

A Mild and Efficient Oxidation of Alcohols in Water

A mild and efficient oxidation of alcohols to the corresponding carbonyl compounds using the PhI(OAc)2 (1.1 eq.) with n-Bu4NBr (8 mol %) in water at room temperature is described.This new procedure is very simple and affords the desired carbonyl compounds in high yields.     

铜模板交联壳聚糖对金属离子的吸附性能研究

研究了壳聚糖对CuSO4、Cu(Ac)2、Cu（NO3)2和CuCl2溶液中铜离子的吸附性能，并以各种铜盐为模板合成了戊二醛交联树脂，考察该树脂了对金属离子的选择吸附性能．结果表明，交联树脂对铜离子有较强的“记忆”功能，且以硫酸铜为模板的壳聚糖较其它盐的模板有更高的吸附量和选择性．     

Rh(acac)(CO)2的振动光谱及其简正坐标分析

Rh(acac)(CO)_2是烯烃氢甲酰化、氢硅化及一氧化碳加氢反应重要催化剂.晶体具有红绿二色性·在4000至80cm~(-1)范围测定了其红外和拉曼光谱;采用简化的一般价力场(SGVFF),对观测谱带进行了简正坐标分析。1 实验方法Rh(acac)(C0)_2按文献方法合成,并重结晶。红外光谱:用CsI压片在P-E 983G红外光谱仪上测试了4000～180cm~(-1)范围内的光谱,分辨率2cm~(-1).550～80 cm~(-1)波段在Digilab FTS-20E/D-V真空型傅氏光谱仪上得到。     

双(2,2-二硝基丙基)肼甲硼氢络合物的合成及性能研究

本文报道了双(2,2-二硝基丙基)肼甲硼氢络合物的合成及其性能。实验表明,该络合物在较低温度下(0～5℃)有一定安定性,放置几天后,基本不变,在稍高温度下(20～25℃)放置1～2小时即迅速分解,自燃或自爆。此外,还讨论了可能的机理。     

PEG-400 as an efficient reaction medium for the synthesis of 2,4,5-triaryl-1H-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles

An efficient protocol for the one-pot multicomponent synthesis of various 2,4,5-triaryl- IH-imidazoles and 1,2,4,5-tetraaryl-1H-imidazoles using PEG-400 as reaction medium is described. This method has the advantages of good yields, less pollution and simple reaction conditions.     

Synthesis of gibbilimbols B and D by a modified Ramberg-Bcklund reaction

Gibbilimbols B and D were synthesized from the facile rearrangement of sulfone in the presence of dibromodifluoromethane and alumina-supported KOH in dichloromethane,followed by refluxing the rearrangement products in conc.HCl and methanol and then treating with thiophenol in the presence of AIBN.