乌桕桕脂中甾醇和其它成分分离鉴定

通过柱层析、薄层层析等化学方法,从乌桕桕脂中分离得到甾醇及脂肪酸酯类化合物。经气相色谱和气-质联用分析,鉴定出下列化合物:β-谷甾醇、菜油甾醇、Δ~7-豆甾烯醇、肉豆蔻酸甲酯、肉豆蔻酸乙酯、棕榈酸甲酯、硬酯酸甲酯和硬酯酸乙酯。     

山石榴果实挥发油的化学成分分析

采用超临界CO2提取山石榴果实挥发油,并利用GC-MS联用技术分析挥发油的化学组成。从山石榴果实挥发油中分离、鉴定出33个化合物,占挥发油总量的89.43%。挥发油主要由各种酯、脂肪酸成分组成,含量较高的成分是11,14-二十碳二烯酸甲酯(11,14-eicosadienoic acid,methyl ester,42.49%),棕榈酸(pal mitic acid,15.34%),硬脂酸(stearic acid,10.54%),肉豆蔻酸(myristic acid,6.26%),十六酸乙酯(hexa-decanoic acid,ethyl ester,5.84%)。     

维药瘤果黑种草籽化学成分研究

为研究维药瘤果黑种草籽的化学成分,采用硅胶、ODS柱色谱等方法分离纯化,分离并鉴定了16个化合物,利用理化性质及波谱方法鉴定化学成分的结构分别为:Nigeglanine(1)、附子碱(2)、L-色氨酸(3)、L-色氨酸甲酯(4)、5,7-二羟基-异苯并呋喃酮(5)、豆甾醇(6)、豆甾醇-3-O-β-D-葡萄糖苷(7)、β-谷甾醇(8)、β-胡萝卜苷(9)、亚油酸(10)、邻苯二甲酸二丁酯(11)、棕榈酸(12)、十六烷酸1-甘油酯(13)、硬酯酸(14)、硬酯酸2-甘油酯(15)和蔗糖(16)。其中化合物3～5、7、9、11和15为首次从该种药材中得到。     

海南红厚壳果实精油的化学成分分析

用水蒸气蒸馏法提取海南红厚壳果实挥发油,利用GC-MS技术对其进行化学成分分析鉴定。从红厚壳果实精油中检测到37个化学成分,鉴定了其中的33个化合物,占总含量的99．26％．主要成分为：邻苯二甲酸二丁酯28．80％、棕榈酸7．07％、硬酯酸8．05％、油酸乙酯18．53％、9,12-十八二烯酸甲酯17．45％。     

燕子掌挥发油化学成分的研究

应用气象色谱-质谱联用技术对燕子掌挥发油化学成分进行了分析研究,共鉴定出66种组分与燕子掌主要挥发性化学成分以苯乙醇、2,6,6-三甲基-2,4-环庚二烯-1-酮、6,10,14-三甲基十五烷-2-酮、十六烷酸甲酯、十六烷酸乙酯、十八烷酸甲酯为主要成分,化合物类型以酮、酯、类等化合物为主,其中十六烷酸甲酯的含量最高,占挥发油总量的26．13％。     

榅桲的化学成分及其挥发油的GC-MS分析

采用常规水蒸气蒸馏法提取出榅桲挥发油,经气相色谱／质谱联用方法分析,分离鉴定出18种成分,主要成分有乙酸十二酯、环壬烷酸乙酯、14-十五碳烯酸、7,10,13-十二烷三烯酸甲酯、4．葵烯酸乙酯和5．甲基壬酸乙酯,并用化学方法分析了榅桲的化学成分。     

沙棘油可挥发成分及其不皂化物成分的研究

本研究采用 JMS-D300气质联用仪和日立163气相色谱仪分别对沙棘油及其皂化物中可挥发性成分进行定性和定量测定。从沙棘油挥发物中共确定28种化合物,主成分为3-甲基丁酸甲基丁酯,3-甲基丁酸丙酯,开已酸乙酯和辛酸乙酯等。沙棘油不皂化物的成分主要是脂肪酸酯类,维生素E和甾醇类化合物,其中主成分为十八碳烯酸甲酯,α-维生素E和β-谷甾醇,其总和占总不皂化物的一半以上。VE及甾醇在本实验条件下的GC分离效果较佳,将为进一步研究其GC定量法提供有价值的参考。     

红花绿绒蒿的非生物碱成分

本文对红花绿绒蒿的非生物碱成分进行了研究。分离并用波谱法鉴定了的其中6个成分为:21α-羟基熊果酸(1),肉豆蔻酸2,3-二羟基丙酯(2),豆甾醇(3),β-香树精(4),熊果酸(5)及胡萝卜甙(6)。     

油菜甾醇内酯类化合物结构与活性的相关性

比较了19种油菜甾醇内酯类似物和有关甾体化合物在水稻叶片倾斜及萝卜幼苗生长试验中的生物活性。表油菜甾醇内酯(24—Epi—BR)在两个系统中都具有很强的生物活性。C_2位失去羟基(香蒲甾醇)仅在水稻试验中有高活性,改变C_22位侧链结构(2α,3α双羟基—6—酮—23,24—双失碳—β—高-5α—胆烷酸甲酯)在萝卜试验中仍有活性。     

瑞香狼毒茎叶化学成分研究

新鲜瑞香狼毒(Stellera chamaejasme)茎叶经正已烷提取,脱腊后进行GC-MS-DS联用分析,鉴定出20个化合物。主要成分为正十八烷;正十九烷;2,6,10,14 — 四甲基十六烷;十六烷酸;十六烷酸甲酯;十六烷酸乙酯;9,12,15-十八碳三烯酸甲酯;9,12-+八碳二烯酸;9,12,15-十八碳三烯酸和十八烷酸。     

Lipase-Catalyzed Synthesis of Capsaicin Analogs by Amidation of Vanillylamine with Fatty Acid Derivatives

Various lipases catalyzed the synthesis of capsaicin analogs by amidation of vanillylamine with fatty acid derivatives in a two-phase system. When methyl myristate was employed as an acyl donor, moderate yields, 40-59%, of capsaicin analog (3) were obtained using Novozym 435, Lipase AK or Lipase PS. Several capsaicin analogs having 4-18 carboxyl carbons were also synthesized from the corresponding fatty acid or its methyl or ethyl ester in 2-44% yields.     

3种红枣的挥发性化学成分的乙醇提取及测定

新鲜成熟的去核油枣、木枣及团枣用95％乙醇浸泡,低温蒸除乙醇、膏状物用乙醚萃取,用气相色谱－质谱联用仪测定乙醚溶液。结果表明,3种新鲜成熟的红枣的挥发性成分主要为棕榈烯酸乙酯、棕榈酸乙酯、肉豆蔻乙酯、亚油酸乙酯、油酸乙脂、月桂酸乙酯、硬脂酸乙酯、苹果酸二乙酯、葵酸乙酸等16种酯类,以及乙酸和棕榈烯酸等2种酸和3－羟基－2－丁酮。不同品种的红枣中所含酯类的多少及含量的高低均有所差异。在同一种红枣的果肉中检测到16种酯类尚属首次报道。     

Mixed monolayer studies of 12-hydroxyoctadecanoic acid and its esters

Mixed monolayers of two bipolar/bipolar systems have been studied and the results are compared with those obtained from similar monopolar/monopolar systems. DL-12-Hydroxyoctadecanoic acid, methyl DL-12-hydroxyoctadecanoate, and ethyl DL-12-hydroxyoctadecanoate were used as the bipolar substances in this paper. The surface pressure-area/molecule isotherms of both the DL-12-hydroxyoctadecanoic acid/methyl DL-12-hydroxyoctadecanoate system and the methyl DL-12-hydroxyoctadecanoate/ethyl DL-12-hydroxyoctadecanoate system were measured at a variety of compositions and temperatures. Taking advantage of the thermodynamic threatment which has been formulated by Motomura, the two-dimensional phase diagrams and the apparent molar entrophy, enthalpy and energy changes were evaluated for both systems. The DL-12-hydroxyoctadecanoic acid/ethyl DL-12-hydroxyoctadecanoate system exhibited a deformed cigar type diagram while the methyl DL-12-hydroxyoctadecanoate/ethyl DL-12-hydroxoctadecanoate system formed a normal cigar type diagram. The transition thermodynamic quantities of both the DL-12-hydroxyoctadecanoic acid/ethyl DL-12-hydroxoctadecanoate system and the methyl DL-12-hydroxyoctadecanoate/ethyl DL-12-hydroxyoctadecanoate system were respectively much larger than those of similar monopolar/monopolar systems: hexadecanoic acid/ethyl hexadecanoate and ethyl hexadecanoate/ethyl heptadecanoate.     

发酵无花果香料的挥发性成分分析

利用微生物发酵无花果开发特色香料,并采用同时蒸馏萃取装置收集挥发性成分并用气相色谱一质谱仪对生物技术制备的无花果香料挥发性成分进行分离和鉴定,经毛细管色谱分离出47种组分,确认了其中的45种成分,并用面积归一化法测定了各种成分的百分含量,其主要成分为：9,12-十八碳二烯酸乙酯(27．34％)、十六酸乙酯(23．99％)、邻苯二甲酸二丁酯(6．18％)、邻苯二甲酸二异丁酯(5．52％)、9,12-十八碳二烯酸甲酯(4．72％)、十六酸甲酯(4．67％)、9,12,15-十八碳三烯酸乙酯(4．48％)、9-十八碳烯酸乙酯(3．80％)、糠醛(2．53％)、9,12,15-十八碳三烯酸甲酯(1．85％)、十八酸乙酯(1．42％)、9-十八碳烯酸甲酯(1．26％)等。     

Transglucosidation of methyl and ethyl D-glucofuranosides by alcoholysis

The acid catalyzed ethanolysis of methyl 5-O-methyl-alpha- and -beta-D-glucofuranoside and the analogous methanolysis of ethyl 5-O-methyl-alpha- and -beta-D-glucofuranoside have been investigated. For all four reactions, the primarily formed transglycosylation product was a single glycoside that had the opposite anomeric configuration to the starting material. This strongly indicates that a D-glucose methyl ethyl acetal is first formed and is then ring closed by a nucleophilic attack by HO-4, giving either the starting material or a transglycosylation product with the opposite anomeric configuration. Low percentages of the methyl ethyl acetals and of dimethyl acetals were also observed in the reaction product during the methanolysis reactions.     

Biosynthesis and urinary excretion of methyl sulfonium derivatives of the sulfur mustard analog, 2-chloroethyl ethyl sulfide, and other thioethers

Thioether methyltransferase was previously shown to catalyze the S-adenosylmethionine-dependent methylation of dimethyl selenide, dimethyl telluride, and various thioethers to produce the corresponding methyl onium ions. In this paper we show that the following thioethers are also substrates for this enzyme in vitro: 2-hydroxyethyl ethyl sulfide, 2-chloroethyl ethyl sulfide, thiodiglycol, t-butyl sulfide, and isopropyl sulfide. To demonstrate thioether methylation in vivo, mice were injected with [methyl-3H]methionine plus different thioethers, and extracts of lungs, livers, kidneys, and urine were analyzed by high-performance liquid chromatography for the presence of [3H]methyl sulfonium ions. The following thioethers were tested, and all were found to be methylated in vivo: dimethyl sulfide, diethyl sulfide, methyl n-propyl sulfide, tetrahydrothiophene, 2-(methylthio)ethylamine, 2-hydroxyethyl ethyl sulfide, and 2-chloroethyl ethyl sulfide. This supports our hypothesis that the physiological role of thioether methyltransferase is to methylate seleno-, telluro-, and thioethers to more water-soluble onium ions suitable for urinary excretion. Conversion of the mustard gas analog, 2-chloroethyl ethyl sulfide, to the methyl sulfonium derivative represents a newly discovered mechanism for biochemical detoxification of sulfur mustards, as this conversion blocks formation of the reactive episulfonium ion that is the ultimate alkylating agent for this class of compounds.     

Odoriferous compounds from the flowers of the conifers Picea abies,pinus sylvestris and Larix sibirica

A GC/MS analysis of the volatile constituents from the flowers of Norway Spruce, Picea abies, has been carried out. The volatile constituents of the female flowers were distinctly different from those of the male flowers and the twigs. Characteristic constituents are methyl and ethyl benzoate, methyl and ethyl salicylate, methyl and ethyl butanoate, borneol and bornyl acetate. In the scent from the male flowers we could only detect the same monoterpenes as in the twigs. In Larix sibirica methyl benzoate, methyl salicylate, borneol and bornyl acetate were detected in the female flowers and, in the female flowers of Pinus sylvestris, methyl salicylate was found.     

横断山区莎草科新分类群（一）

作者于1981—1983年随中国科学院青藏综合科学考察队赴横断山区考察,采集到不少莎草科植物标本。近年来、在承担《横断山区植物》一书莎草科的编著任务中,除鉴定了青藏队采集的该科标本外,还鉴定了我所标本馆收藏的该科部分标本,发现了一些新分类群,现在本文发表.     

Activities of 2,4-dihydroxy-6-n-pentylbenzoic acid derivatives

Esters of 2-hydroxy-4-methoxy-6-n-pentylbenzoic acid (2-8) (methyl, ethyl, butyl, pentyl, isopropyl, sec-butyl and benzyl), olivetol (9), methyl, ethyl, butyl perlatolates (10-12), 2,4-dihydroxy-6-n-pentylbenzoic acid (15), and methyl and ethyl esters of (15) were prepared through structural modifications of perlatolic acid (1) with the aim to detect new antifungal and antibacterial substances and also to evaluate the toxicity by the brine shrimp lethality assay against Artemia salina. The antifungal assays were carried out against the fungus Cladosporium sphaerospermum through the bioautography method, and methyl 2,4-dihydroxy-6-n-pentylbenzoate (13) showed the highest antifungal activity (2.5 yg). Olivetol (9) and 2,4-dihydroxy-6-n-pentylbenzoic acid (15) are also potent inhibitors of the growth of the fungus (5.0 microg). Except for methyl (10), the ethyl (11) and butyl (12) perlatolates were less active than perlatolic acid (1). The activities presented by methyl (2) and ethyl (3) 2-hydroxy-4-methoxy-6-n-pentylbenzoates and methyl (13) and ethyl (14) 2,4-dihydroxy-6-n-pentylbenzo-ates suggest that compounds with a free hydroxy group in the aromatic ring (C-4) have a more pronounced effect against C. sphaerospermum. Antibacterial activities were tested by the disc diffusion method using pathogenic strains of S. aureus and E. coli. The compounds were weakly active with inhibition zones between 9-15 mm. The 2-hydroxy-4-methoxy-6-n-pentylbenzoic esters 2-8 and alkyl perlatolates 10-12 were selective against E. coli. Perlatolic acid (1) and methyl 2-hydroxy-4-methoxy-6-n-pentylbenzoate (2) were the most active with LD50 values of 24.1 microM and 27.2 microM, respectively. The other compounds were not toxic to Artemia salina larvae.     

Transesterification of canola oil in mixed methanol/ethanol system and use of esters as lubricity additive

Transesterification of canola oil was carried out with methanol, ethanol, and various mixtures of methanol/ethanol, keeping the molar ratio of oil to alcohol 1:6 and using KOH as a catalyst. Mixtures of alcohol increased the rate of transesterification reaction and produced methyl as well as ethyl esters. The increased rate was result of better solubility of oil in reaction mixture due to better solvent properties of ethanol than methanol and equilibrium due to methanol. With 3:3 molar ratio of methanol to ethanol {MEE (3:3)} the amount of ethyl ester formed was 50% that of methyl ester. Properties (acid value, viscosity, density) of all esters including mixed esters were within the limits of ASTM standards. Lubricities of these esters are in the order: ethyl ester>methyl ethyl ester>methyl ester.