Asymmetric Hydrogenation Synthesis of （S）-（＋）-2-（6＇-methoxyl-2-naphthyl） propionic Acid by Cinchona Modified Pd（0）-α-FeOOH Catalyst

Asymmetric hydrogenation of (6-methoxyl-2-naphthyl)-2-acrylic acid catalyzed by cinchona modified Pd(0)-α-FeOOH was reported and ee‘s of (S)-( )-2-(6‘-methoxyl-2-naphthyl)propionic acid ((S)-( )-naproxen) up to 98% was achieved firstly.     

Studies on the Synthesis of a Natural Product—Piceatannol and its Analogs

Piceatannol,(E)-3,3′,4,5′-tetrahydroxy stilbene, a natural polyhydroxy stibene, possesses many biological activities, its synthesis has been reported. We designed another route of its synthesis, which can be controlled more easily. The synthetic product was characterized by elemental analysis,IR,MS and ^1H-NMR. Its analogs were synthesized by the similar method.     

Saluenolide A,A Novel Eremophilanolide from Senecio saluenensis

From Senecio saluenensis, a novel eremophilanolide Saluenolide A was isolated. Its structure was elucidated by 2D-NMR technique and X-ray diffraction.     

Sebiferone,a New Triterpenoid from Stem Bark of Sapium sebiferum （L.）Roxb.

From the stem bark of Sapium sebiferum a new triterpenoid,anmed sebiferone (1),was isolated.The structure of the new compound was clucidated as 3β-acetoxy-D-friedoolen-14-en-1-one-28-oic acid on the basis of spectral and chemical methods.     

Four New Isovalertatins M33, D13, D33, and D43, from the Culture Filtrate of Streptomyces luteogriseus

In a program of investigating the chemical constituents of the potentially α-amylase- inhibiting complex, WC670, extracted from the culture filtrate of Streptomyces luteogriseus, we found it contains the known aminooligosaccharides, isovalertatins M03, M…     

New Xanthones from Polygala crotalarioides

Introduction Xanthonesaresecondarymetabolitescommonly occurringinafewhigherplantfamilies,fungiandli chen.Theirhightaxonomicvalueinsuchfamiliesand theirpharmacologicalproperties,includinginvitrocy totoxicity,invivoantitumouractivity,antifungal,anti bacteri…     

Bandunamide, a Novel Cyclopeptide from the Streptomyces Griseovariabilis bandungensis

A new cyclic octapeptide, bandunamide, was isolated from the acetone extracts of streptomyces griseovariabilis bandungensis. This cyclic octapeptide exhibits strong antimicrobial activity against Phytophthora drechsleri (IC50=15 ng/mL), Colletotrchum higginsiannum(IC50=15.6 ng/mL), Piricularia oxyzae (IC50=0.2 μg/mL), and Fusarium oxysporum f. Sp.(IC50= 100μg/mL). The structure elucidation of bandunamide is herein reported.     

HPLC法对5种红豆杉属植物中紫杉烷类化合物成分的分析

采用快速真空液相层析法(VLC)富集红豆杉属植物中5种主要紫衫烷类化合物,回收率在95%以上.5种红豆杉植物中紫杉烷类化合物含量测定结果显示:加拿大红豆杉(树皮)中10-DABⅢ和9-羟基-13-乙酰基巴卡亭Ⅲ含量较高;东北红豆杉(树皮)中7-木糖紫杉醇和三尖杉宁碱含量较高;而紫杉醇含量在东北红豆杉(树皮)中最高,曼地亚(枝叶,搁置一年)次之;本文首次发现矮紫杉中含有4种紫杉烷类化合物.     

浙江槭属植物新记录

作为浙江槭属植物区系的补充，报道了浙闽槭Acer johnedwardianum F.P.Metcalf、乳源槭A. chunii Fang和九江三角枫A. buergerianum Miq. var. jiujiangense Z.X. Yu 3个植物分布新记录；补充描述了浙闽槭、乳源槭花的形态特征；恢复了浙闽槭的种级地位。     

Rb2MGe3S8 (M=Zn,Cd): [MGe3S8]2–单元构型变换导致化合物从中心到非心的转变※

在本工作中, 利用高温固相法成功合成了两个碱金属硫属化合物Rb₂MGe₃S₈ [M=Zn (1), Cd (2)]. 化合物1, 2都为二维层状结构且均具备大的光学带隙, 化合物1和2的实验带隙分别为3.24和3.16 eV. 化合物1属于P-1中心对称群, 化合物2属于非心P2(1)2(1)2(1)空间群且具有一定的非线性光学(NLO)效应, 在粒径为50~75 μm时与KH₂PO₄ (KDP)相当(@1064 nm). 化合物2的激光损伤阈值为AgGaS₂的16.6倍. 化合物1, 2的分子式化学计量比相同但展示不同的对称性, 通过分析它们的晶体结构发现, 其基本构造单元[MGe₃S₈]^2–在两化合物中构型的不同导致化合物1、2对称性发生中心到非心的转变. 为了深入了解化合物2的NLO效应的起源, 基于密度泛函理论对其进行了电子能带结构和NLO极化率的理论计算.