Sesquiterpene lactones from Saussurea alata

Two new guaianolides, namely, 3beta,8alpha-dihydroxy-13-methoxyl-4(14),10(15)-dien-(1alphaH,5alphaH,6beta H,11betaH)-12,6-olide (1) and 3beta,8alpha-dihydroxy-13-methoxyl-4(14),10(15)-dien-(1alphaH,5alphaH,6beta H,11alphaH)-12,6-olide (2), together with six known guaianolides, 8-hydroxyzaluzanin C, austricin, chlorojanerin, cynaropicrin, chlorohyssopifolin E and chlorohyssopifolin A were isolated from the aerial parts of Saussurea alata. The structures were established mainly based on spectral analysis, especially 2D NMR techniques.     

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

During the past decades enormous progress was made in asymmetric catalytic synthesis, an well-known example is BINAP1, the chiral hydrogenation synthesis of S-(+)-naproxen catalyzed by BINAP-Ru dicarboxylate complexes provides excellent enantioselectivity (up to 99% ee) and good chemical yield (92%), however the pressures is relatively high (135-150 atm) and the (S)-BINAP-Ru(III) complex is very expensive. This problem may present a practical limitation. In recent years new methodolo…     

A New Pyrone Derivative from Fungus Cephalosporium sp. AL031

Cephalosporium sp. AL031 is a fungus isolated from Sinarundinaria nitida grown in the Ailao Mountain, Yunnan, China. It produces, in cultures, antibacterial and fungicidal secondary metabolites, according to the antimicrobial activity test1. In previous p…     

利用Diels-Alder反应构建桉烷类倍半萜骨架关键中间体的研究

以3-甲基-1,3-间苯二酚和异戊醛为原料分别合成亲双烯2-甲氧基-6-甲基对苯醌和双烯1-甲氧基-3-异丙基-1,3-丁二烯,通过Diels-Alder反应,高区域选择性地得到桉烷类倍半萜骨架中间体2c.     

dl-萘普生的简便合成及其光学异构体的拆分

萘普生(S)-(+)-2-(6-甲氧基-2-萘基)丙酸(1)是一种新型非甾体抗菌消炎药物,临床应用十分广泛,疗效显著^[1]。其分子结构中有一个不对称碳原子,S体比R体的药理作用要强28倍^[3]。     

The synthesis of key intermediates in cembranolides

Two key intermediates of cembranolides- (2E,6E,10E)-3,7,11,15-tetramethyl-9-phenylsulfonyl-2,6,10,14-tetraen-1-hexadecanol (1) and (2E,6E,10E,14E)-2,6,10,14-tetramethyl-8-phenylsulfonyl-2,6,10,14-tetraen-1,16-hexadecanediol (2) were synthesized starting from geraniol and linalool and some improved synthetic methods were used.     

A new glycoside from the leaves of Neoalsomitra integrifoliola

A new ionone glycoside （6R,9R）-blumenyl α-L-rhamnopyranosyl-（1 → 6）-β-D-gluco-pyranoside （1）, together with a new natural product 2-methoxyl-4-trans-pmpenyl-phenol α-L-rhamnopyranosyl-（1 → 6）-β-D-glucopyranoside （2）, was isolated from the leaves ofNeoalsomitra integrifoliola. Their structures were elucidated by chemical and spectral analysis. Compound 1 showed weak anti-inflammatory and low-level antioxidant activities.     

Three new ingol diterpenes from Euphorbia nivulia: evaluation of cytotoxic activity

The latex of Euphorbia nivulia afforded three new ingol diterpenes, 3-acetyl-8-methoxyl-7-angolyl-12-hydroxylingol (7), 3,12-diacetyl-7-hydroxy-8-methoxylingol (8), and 3,12-diacetyl-7-angolyl-8-hydroxylingol (9) along with five known ingol diterpenes 2-6 and a known triterpene cyclonivulinol (1). Their structures were established by means of spectroscopic analysis. Diterpenes 2-9 were evaluated for their cytotoxic activity.     

Two new lavandulyl flavonoids from Sophora flavescens

Two novel lavandulyl flavonoids, (2S)-7-methoxyl-4",5"-dihydroxynorkurarinone (1) and (2S)-6"-hydroxynorkurarinone-7-O-beta-D-galactoside (2), were isolated from the rhizome of Sophora flavescens. Their structures were elucidated by spectral methods, including 2D NMR spectroscopy. Both compounds showed cytotoxic activity against Hela cells, with 2 being more active than 1.     

A Practical Synthesis of (S)-(+)-2-(6-methoxyl-2-naphthyl) propionic Acid

a-Arylpropionic acids are an important class of non-steroidal anti-inflammatory agents1,2. The therapeutic efficacy of this class of drugs is well demonstrated by the introduction and extensive use of more than a dozen compounds exemplified by ibuprofen, naproxen, ketoprofen and flurbiprofen etc. However, in recent years the use of enantiomerical pure drugs in chemotherapy is becoming almost mandatory for enhancing specificity of drug action and reducing the toxicity. This awareness led to …     

Hepatoprotective phenylethanoid glycosides from Cirsium setosum

Two new phenylethanoid glycosides, namely β-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(3-methoxyl-4-hydroxyphenyl)-8-propenoate] (1) and β-D-glucopyranoside, 1″-O-(7S)-7-(3-methoxyl-4-hydroxyphenyl)-7-methoxyethyl-3″-α-L-rhamnopyranosyl-4″-[(8E)-7-(4-hydroxyphenyl)-8-propenoate] (2), together with six phenylethanoid glycosides were isolated from Cirsium setosum. Their structures were elucidated by their spectroscopic data and references. Compounds 2, 4, 5, 7 and 8 (10 μM) exhibited moderate hepatoprotective activities. Compounds (3–8) were obtained from this plant for the first time.     

3，5—环—孕甾—6—甲氧基—20—S—22—醛的立体选择性合成

油菜甾醇内酯(brassinolide)(1)是一种高效植物生长激素,一些实验室曾成功地进行了合成(图1)。这些合成路线不少是以20-S-22-甾醛为关键中间体,再分步接上侧链的,而C_(20)-S-22-甾醛大都由豆甾醇为原料制得。考虑到豆甾醇来源困难,我们采用国内资源丰富、价格低廉的薯蓣皂甙元为起始原料,立体选择性地合成了C_(20)-S-22-甾醛化合物7(见图2),对1及其     

尿中莠去津去烃基代谢物的特丁二甲硅烷基衍生化/气相色谱-质谱联用分析法

建立了尿中除草剂莠去津(ATRZ)代谢物去乙基莠去津(DEA)、去异丙基莠去津(DIA)及去乙基去异丙基莠去津(DDA)的分析方法.尿样加入内标2-氨基-4-甲氧基-6-甲基-1,3,5-三氮嗪(AMMT),碱化后用高极性GDX501大孔树脂吸附、乙酸乙酯洗脱进行固相萃取,萃取物在乙腈溶剂中用N-甲基-N-特丁二甲硅烷...     

T(4-Mop)PS4卟啉与牛血清蛋白相互作用的研究

以四-(4-甲氧基-3-磺酸基苯)卟啉(T(4-Mop)PS4)为探针,通过T(4-Mop)PS4与牛血清白蛋白(BSA)的相互作用,建立了测定BSA的电化学分析方法。T(4-Mop)PS4的峰电流变化(ΔIp)与BSA在2.0×10-6～1.0×10-5mol.L-1范围内呈良好的线性关系,检出限为1.2×10-6mol.L-1;对5.0×10-6mol.L-1BSA平行测定8次,其相对标准偏差为2.0%,回收率为95%～104%。组氨酸、缬氨酸、苯丙氨酸、丝氨酸、异白氨酸、谷氨酰胺、苏氨酸等氨基酸对BSA的测定不产生干扰。采用紫外可见光度法、荧光光谱法和线性扫描伏安法(LSV)研究了T(4-Mop)PS4与BSA之间的相互作用,并测定了二者相互作用的结合常数和结合比。研究表明,T(4-Mop)PS4与BSA之间主要以疏水作用力结合,形成了1∶1的稳定复合物。     

2-氨基-6-甲氧基-3-硝基吡啶的合成

以2-氯-5-硝基吡啶为原料,经甲氧基化反应得2-甲氧基-5-硝基吡啶(2),2再与液氨/高锰酸钾进行氨化反应制得2-氨基-6-甲氧基-3-硝基吡啶,总收率77%。     

Two new triterpenoid saponins from notoginseng medicinal fungal substance

Two new triterpenoid saponins, named ginsenoside Rh₁₀ (1) and notoginsenoside ST-6 (2), were isolated from notoginseng medicinal fungal substance. Their structures were elucidated by a combination of 1D and 2D NMR, MS and chemical analysis.     

聚碳酸亚丙酯洗涤工段洗涤液组分分析

采用气质联用法对聚碳酸亚丙酯（PPC）生产工艺中洗涤工段洗涤液组分进行定性及定量分析。分析结果表明洗涤液中的杂质主要有1-甲氧基-2．丙醇、2-甲氧基-1-丙醇、碳酸二甲酯、二丙撑二醇、碳酸丙烯酯。1次洗涤液中含环氧丙烷32．34％,含甲醇58．74％;4次洗涤液中含环氧丙烷10．61％,含甲醇89．01％。随着洗涤次数的增加,样品中环氧丙炕含量减小,甲醇含量增大。     

GC/MS分析羰基化产物萘普生甲酯

α－（6-甲氧基-2-萘基）-乙醇在催化剂的作用下,与甲醇和CO发生羰基化反应,一步生成α－（6-甲氧基-2-萘基）丙酸甲酯（萘晋生申酯）。应用气相色谱-质谱联用技术,对这个反应过程中生成的各种化合物进行了分析,获得两个中间产物6-甲氧基萘乙烯和1-甲氧基-1-（6'-甲氧基-2'-萘基）乙烷的GC／MS数据资料,为推测该催化反应机理提供了可靠的依据。     

含中心功能基氮支套索冠醚化合物的合成及其钠离子络合物的晶体结构

借模板法由6,9-二氧杂-3,12-二氮杂-十四烷-1,14-二醇分别与4-甲基(或氯)-2,6-二溴甲基苯甲醚在乙腈中, 以无水碳酸钠为缩合剂, 制得两种尚未见文献报道的含中心功能基氮支套索冠醚化合物: N,N'-二羟乙基-16-甲基-18-甲氧基-6,9-二氧杂-3,12-二氮杂-二环[12.3.1]十八-1(18),14,16-三烯(4a)和N,N'-二羟乙基-16-氯-18-甲氧基-6,9-二氧杂-3,12-二氮杂-二环[12.3.1]十八-1(18),14,16-三烯(4b)的钠离子络合物3a和3b。4a和4b经元素分析、红外光谱、核磁共振谱和质谱证实其组成和结构。借四圆衍射仪测定了3b的晶体结构和分子结构。     

Approach toward the total synthesis of 5-hydroxyaloin A

The synthesis of a thiomethyl analogue of 5-hydroxyaloin A has been achieved using benzyne and naphthyne [4 + 2] cycloadditions with substituted furans. A regiocontrolled cycloaddition was achieved using a silicon tether, and a regioselective ring opening was accomplished using a sulfide as a directing group.