The First Total Synthesis of 3-Oxo-11,12,13-trihydroxyeudesm-4-ene

The first total synthesis of 3-oxo-11,12,13-trihydroxyeudesm-4-ene,a highly oxygen- ated natural eudesmane, was described.

The Chemical Constituents of Amoora yunnanensis

Two new sterols, 3 beta, 7 alpha, 16 beta -trihydroxy-stigmast-5,22-diene (1), 3 beta, 7 alpha, 16 beta -trihydroxy-stigmast-5-ene (2), were isolated together with six known compounds, ergosta-5, 24(28)-dien-3 beta, 7 alpha -diol (3), ergosta-5,24(28)-dien-3 beta, 7 beta, 16 beta -triol (4), beta -amyrone (5), beta -amyrin (6), 11 alpha, 12 alpha -epoxy-14-taraxeren-3-one (7), and 6-guaiene-4 alpha, 10 alpha -diol (8) from the EtOH extract of the bark of Amoora yunnanensis (H. L. Li) C. Y. Wu. Their structures were deduced on the basis of spectral data.

白车轴草化学成分的分离与鉴定

目的为白车轴草(Trifolium repensL.)的药效物质基础提供依据。方法利用制备薄层、反复硅胶、Sephadex LH-20、开放ODS柱色谱等方法进行分离纯化,根据理化性质及波谱分析对分离得到的化合物进行结构鉴定。结果分离得到10个化合物,分别鉴定为伞形花内酯(umbelliferon,1)、芒柄花素(formononetin,2)、水杨酸(salicylic acid,3)、双白瑞香素(daphnoretin,4)、4′-methoxy-coumestrol(5)、trifoliol(6)、美迪紫檀素(medicarpin,7)、环阿尔廷-25-烯-3β,24ξ-二醇(cycloart-25-en-3β,24ξ-diol,8)、3β-hydroxy-7α-methoxy-24β-ethyl-cholest-5-ene(9)、soyasapogenol B(10)。结论化合物8、9为首次从车轴草属植物中分离得到,化合物1、3、4为首次从白车轴草中分离得到。

DBU-based CO2 absorption-mineralization system: Reaction process,feasibility and process intensification

Amine-based carbon dioxide(CO2)capture is still limited by high desorption energy consumption.Fixing CO2 into carbonate is a safer and more permanent method.In this work,calcium oxide(CaO)is introduced to perform chemical desorption instead of thermal desorption on 1,8-diazabicyclo[5.4.0]undec-7-ene(DBU)aqueous solution after CO2 absorption.The X-ray diffraction(XRD)patterns of solid products show the formation of calcite calcium carbonate(CaCO3),which prove the feasibility of this method.The effects of reaction temperature,reaction time and Ca2+/CO32-molar ratios on the related reactions in CO2 absorption-mineralization process and CaCO3 precipitation are discussed,and purer CaCO3 is obtained by ultrasonic treatment.The CaCO3 content can be increased to 95.8%and the CO2 desorption ratio can achieve 80%by 30 min ultrasonic dispersion treatment under the conditions(40℃,180 min,Ca2+/CO32-molar ratio=1.0).After five cycles,DBU aqueous solution shows stable CO2 absorption and mineralization ability.Fourier transform infrared spectroscopy(FT-IR)spectra of the reaction process also indicate the regeneration of the solvent.Compared with thermal desorption,this process is exothermic,almost without no additional heat.

Synthesis and photochromic behavior of mono-,and biphotochromic system linked by p-phenylene bridge

The synthesis of mono- and bis-1,3-diazabicyclo[3.1.0]hex-3-ene derivatives with indole ring and p-phenylene spacer, which behave as photochromic materials, is reported. The structure-photochromic behavior relationship （SPBR） of the synthesized compounds has been analyzed.

Two New Sterols from Amoora yunnanensis

Two new sterols. 3 beta,7 alpha, 16 beta-trihydroxy-stigmast-5,22-diene 1,3 beta,7 alpha,16 beta-trihydroxy-stigmast-5-ene 2. were isolated together with two known ergosterols, ergosta-5,24(28)-diene-3 beta.7 alpha-diol, ergosta-5,24(28)-diene-3 beta,7 beta,16 beta-triol from the bark of Amoora yunnanensis (H. L. Li) C. Y. Wu. Their structures were deduced on the basis of spectral data.

Crystal and molecular structure of 2,3-benzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2-ene

The crystal structure of 2,3-benzo-1,4,7,13-tetraoxa-10-selenacyclopentadeca-2-ene was de- termined,C_(14)H_(20)O_4Se,M_r:331.27,orthorhombic,Pbca,a=18.445(3),b=16.334(4),c9.232(2) ,V=2781.3 ~3,Z=8,Dx=1.582 Mg m^(-3),λ(Mo K_α)=0.71073 ,μ=26.77 cm^(-1),F(000)=1360, T=297 K,R=0.0329,R_w=0.0438 for 2192 reflections with I>3 σ(I).The crystal structure is closely related to that of benzo-15-crown-5(at 123 K),whereas the molecular geometry of the two coronands is different according to their torsion angles calculated and the shapes exhibited.

光皮木瓜叶化学成分

目的:研究光皮木瓜Chaenomeles sinensis叶的化学成分。方法:通过各种色谱法对光皮木瓜叶的甲醇提取物二氯甲烷部位进行分离纯化,利用质谱和核磁共振等光谱技术鉴定化合物结构。结果:从中分离鉴定了11个化合物,分别为10-廿九烷醇(1),植物醇(2),β-谷甾醇(3),(24R)24-ethyl-7α-hydroperoxy-cholest-5-en-3β-ol(4),硬脂酸(5),3β,27-dihydroxy-urs-12-ene(6),白桦脂酸(7),二十烷醇(8),熊果酸(9),2α,3α,19α-三羟基乌索-12-烯-28-酸(10),2α-羟基白桦脂酸(11)。结论:其中化合物2,4,6,8首次从该属中分离得到。