Les sesquiterpenes de Cupressus dupreziana

Heartwood extractives of C. dupreziana were investigated. Carvacrol methyl ether, cedrol and α-cedrene are present, together with sesquiterpene hydrocarbons. A comparison is made with those found in C. sempervirens and other Cupressus species.     

Analyses of the volatile leaf oils of Juniperus deppeana and its infraspecific taxa: Chemosystematic implications

Eight OTUs of Juniperus deppeana were collected and their volatile leaf oils analysed by GC/GCMS. The volatile oils are dominated by oxygenated terpenes such as camphor, linalool, cis-verbenol, 4-terpineol, verbenone, borneol and trans-sabinene hydrate. The major monoterpene found was α-pinene. Sesquiterpenoids were minor components of the volatile leaf oils. The six named taxa were only distinguished by combinations of terpenoid characters. The differentiation of the Arizona J. deppeana (var. pachyphlaea ?) and J.d. forma sperryi from the other taxa in Mexico was the major subdivision found. Juniperus deppeana forma sperryi was clearly distinguished as were J.d. var. robusta and J.d. var. patoniana.     

Essential oil variation in Calyptranthes spruceana

Two chemical races in Calyptranthes spruceana were examined. One of them contains limonene, geranial and perillaldehyde as the main constituents of its essential oil. The other is shown to contain α-pinene, β-pinene, neral and geranial as its major oil components.     

Volatile oil constituents of sagebrush

The volatile oil of Artemisia arbuscula arbuscula contained a new irregular monoterpene, 2,5-dimethyl-4-vinyl-1,5-hexadiene-3-ol (isolyratol), which was isolated and identified by spectral means. The optically pure furanoid (2S,5S)-trans-5-methyl-5-vinyltetrahydrofur-2-yl methyl ketone (arbusculone), was also characterized by transformation to known (2S,5S)-trans-linalyl oxide. The former component has never been isolated from natural sources prior to this study. The neutral pentane extract also contained several previously characterized non-head-to-tail monoterpenes including artemiseole, artemisia ketone, artemisyl acetate, methyl santolinate, and santolina triene, as well as the regular monoterpenes 1,8-cineole, camphor, p-cymene, camphene and the C₆ fragment, terelactone.     

Volatile constituents of spanish origanum (Coridothymus capitatus) essential oil

Analysis of the neutral fraction of Coridothymus capitatus essential oil (Spanish origanum oil) revealed 61 components. Of the new components reported there were 25 monoterpenes, 9 sesquiterpenes, 5 aliphatic, 1 phenol and 1 phenyl ether.     

Volatile oils of mature and juvenile leaves of Juniperus horizontalis: Chemosystematic significance

Comparison of 39 terpenoids between young (juvenile) foliage and mature (adult) foliage from naturally growing plants of Juniperus horizontalis revealed no significant differences. Canonical variate analysis of the terpenoids of J. scopulorum and J. virginiana along with the mature foliage of J. horizontalis and co-plotting juvenile foliage showed a slight loosening of the J. horizontalis group but not enough to blur taxonomic distinctions. These results stand in sharp contrast with the previous work on J. scopulorum and appear to be due to the indeterminant growth pattern seen in J. horizontalis.     

Volatile phenolic constituents of spanish origanum (Coridothymus capitatus) essential oil

Analysis of the phenolic fraction of Coridothymus capitatus essential oil (Spanish origanum oil) indicated 7 major components. One of them is the well known carvacrol and among the others there are one diisopropylphenol and 5 methyldiisopropylphenols, which are found for the first time from a natural source.     

Sesquiterpenes from Artemisia princeps

Copaene, cyperene, caryophyllene, β-farnesene, α-himachalene, γ-humulene and farnesyl acetate were isolated from the root of Artemisia princeps. As a result of isomerization studies on γ-humulene, the main constituent, a preferred conformation was proposed.     

Volatile constituents in leaves of parsley

Volatile chemicals obtained from the leaves of parsley, Petroselinum sativum by steam distillation, isopentane extraction, and head-space analysis were identified by GLC-MS. The presence in leaf oil of α-pinene, β-pinene, myrcene, β-phellandrene, trans-β-ocimene, γ-terpinene, 1-methyl-4-isopropenyl benzene, and 1,3,8-p-menthatriene as shown by earlier investigators was confirmed. In the present studies, the number of volatile chemicals detected in the leaves was extended by an additional 42. Sniffing tests of effluent from a gas chromatograph of a concentrate from parsley leaves showed that 1,3,8-p-menthatriene was only one of several compounds that gave a parsley-like aroma.     

Identification of volatile constituents of Sassafras albidum root oil

Sassafras root bark oil was examined by GC-MS for the possible natural occurrence of 1′-hydroxysafrole a potent hepatocarcinogenic mammalian metabolite of safrole. Six monoterpenes, 2 sesquiterpenes, 6 allylbenzenes, 2 propenylbenzenes, 2 acroleins and 1 benzaldehyde derivative were identified. Eleven out of these 19 sassafras constituents are reported for the first time. However, 1′-hydroxysafrole was not detected.     

Amides and other constituents from acmella ciliata

Fourteen highly unsaturated amides were isolated from Acmella ciliata. Their structures were determined by means of high field ¹H NMR including 2D-NMR, high resolution mass spectrometry and GC-MS. Some considerations on the biosynthesis of the amides are made.     

窄叶火筒树叶挥发油的化学成分分析

火筒树属（Leea L．）全世界约有70种,主产亚洲热带地区,中国分布有6种。火筒树属植物除了是很好的园艺和观赏植物外,许多种类可作药用,具有活血散瘀、愈溃生肌、清热解毒等功效,可用于治疗感冒发热、风湿痹痛、疮疡肿毒、咀嚼痛、跌打损伤、乳房肿痛、毒蛇咬伤,黄疸性肝炎等疾病。国内外对火筒树属植物的药理活性,特别是有关化学成分的研究报道很少。     

Volatile aroma constituents of parsley leaves

The aroma volatiles of a desert parsley were analysed using routine procedures, and 45 constituents were positively identified, including 11 not previously reported as parsley leaf volatiles. One component, 2-(p-tolyl)propan-2-ol, is a new aroma volatile and, together with p-mentha- 1,3,8-triene, may be unique to parsley. Major constituents of the sample were 4-methoxy-6-(prop-2-enyl)benzo-1,3-dioxolan (myristicin) 4,7-dimethoxy-5-(prop-2-enyl)benzo-1,3 dioxolan (apiole), β-phellandrene, p-mentha-1,3,8-triene and 4-isopropenyl-1-methylbenzene. Aroma assessments during GC showed that apiole, in particular, had desirable parsley odour character.     

Terpenes from the essential oil of Cymbopogon distans

A GC/MS study of the hydrocarbon fraction and the fraction containing oxygenated compounds showed the presence of 12 monoterpene hydrocarbons (28.4%), 13 sesquiterpene hydrocarbons (32.8%), 3 sesquiterpene alcohols (27.2%), 2 esters (7.2%) and 3 carbonyl compounds (4.4%) in the essential oil of Cymbopogon distans. Of these, 27 compounds have been identified.     

Biosynthetic relationship of citral-trans and citral-cis in cymbopogon flexuosus (lemongrass)

Use of [¹⁴C,³H]-labelled precursors revealed that leaf blades of Cymbopogon flexuosus converted geraniol (3,7-dimethylocta-trans-2,6-diene-1-ol) into citral-trans with loss of pro-(1S) hydrogen whereas nerol lost the pro-(1R) hydrogen while being converted into citral-cis. Secondly, the citral-trans is converted into citral-cis and vice versa and there is no separate route for the biosynthesis of either of the two aldehyde isomers.     

Essential oil composition of juvenile leaves from coppiced Eucalyptus nitens

The essential oil of Eucalyptus nitens juvenile foliage harvested from coppiced trees contained α-pinene, limonene, 1,8-cineol, cis-ocimene and α-terpineol as principal components. Minor constituents were monoterpene alcohols, ketones, and aldehydes and 3-methylbutanal. Esters not previously identified in E. nitens leaf oil were ethyl 3-methylbutanoate, 3-methylbutyl-3-methylbutanoate, 3-methylbutyl hexanoate and hexyl 3-methylbutanoate.     

长白侧柏枝叶精油化学成分分析

长白侧柏枝叶精油化学成分分析戚继忠．孙广仁,杨文胜（南京林业大学,南京２１００３７）（吉林林学院,吉林１３２０１１）孙仁昌,薛峰（吉林省长白森林经营局,吉林１３４４００）关键词长白侧柏;精油;气－质联用;乙酸香芹酯Ａｎａｌｙｓｉｓｏｎｔｈｅｃｈｅｍｉ...