Showing papers on "Terpene published in 1994"

Diurnal cycle of emission of induced volatile terpenoids by herbivore-injured cotton plant.

Abstract: Cotton plants attacked by herbivorous insect pests emit relatively large amounts of characteristic volatile terpenoids that have been implicated in the attraction of natural enemies of the herbivores. However, the composition of the blend of volatile terpenes released by the plants varies remarkably throughout the photoperiod. Some components are emitted in at least 10-fold greater quantities during the photophase than during the scotophase, whereas others are released continuously, without conforming to a pattern, during the entire time that the plants are under herbivore attack. The diurnal pattern of emission of volatile terpenoids was determined by collecting and analyzing the volatile compounds emitted by cotton plants subjected to feeding damage by beet armyworm larvae in situ. The damage was allowed to proceed for 3 days, and volatile emission was monitored continuously. During early stages of damage high levels of lipoxygenase-derived volatile compounds [e.g., (Z)-3-hexenal, (Z)-3-hexenyl acetate] and several terpene hydrocarbons [e.g., alpha-pinene, caryophyllene] were emitted. As damage proceeded, high levels of other terpenes, all acyclic [e.g., (E)-beta-ocimene, (E)-beta-farnesene], were emitted in a pronounced diurnal fashion; maximal emissions occurred in the afternoon. These acyclic terpenes followed this diurnal pattern of emission, even after removal of the caterpillars, although emission was in somewhat smaller amounts. In contrast, the emission of cyclic terpenes almost ceased after the caterpillars were removed.

Use of terpene compounds for reduced release of arachidonic acid and of inflammation mediators

Abstract: Disclosed is a method of treatment of steroid requiring inflammatory diseases using certain saturated monocyclic and bicyclic terpene compounds. These compounds may be administered in the form of capsules resistant to gastric juice, infusion solutions or intramuscular injection solutions. Because these particular terpene compounds exhibit steroid-like effects but without the harmful side-effects of conventional corticosteroids, the use of corticosteroids is substantially reduced, and in some cases, completely eliminated. Therefore, these terpene compounds are also suitable for long-term therapy and prophylaxis.

Limonene and Related Compounds as Potential Skin Penetration Promoters

Abstract: A transdermal therapeutic system can be developed by promoting the skin permeability of drugs with some materials. In this study, the promoting effect of terpenes present in essential oils on the percutaneous absorption of indomethacin from alcoholic hydrogels was investigated in rats in vivo. The enhancing activity of terpenes was expressed quantitatively as a quadratic function of lipophilicities of the terpenes, measured as a lipophilic index. Further increase in the significant level was observed when the molecular weight of terpenes was included in this function as the second factor. The synergism of ethanol with d-limonene, selected from among the other terpenes, on the promoting activity was statistically investigated. It was evident that both d-limonene and ethanol were important factors for promoting the percutaneous absorption of indomethacin. A significant synergism of d-limonene with ethanol was also observed. As a possible mechanism for enhancement action of d-limonene and ethanol, it...

Terpenes to terpenes. Stereo- and enantio-selective synthesis of (+)-α-elemene and a short route to a versatile diquinane chiron

Abstract: Syntheses of sesquiterpene (+)-α-elemene from monoterpenes (+)-limonene and (+)-2-carene following a new strategy are reported.

Low toxicity terpene drilling fluid and drilling fluid additive

Abstract: A water based drilling fluid comprises 1-8% of an additive comprising saturated terpene, a mixture of saturated terpenes or a mixture of saturated and unsaturated terpenes. The drilling fluid is substantially non-toxic and has an LC-50 greater than 30,000 ppm and preferably greater than 100,000 ppm. The most economic additives are a mixture of saturated and unsaturated terpenes and have at least 30% saturated terpenes. The drilling fluid has the advantage of low toxicity over unsaturated terpene drilling fluids.

Foliage Oil Terpenes of Prumnopitys ferruginea (D. Don) Laubenf. Variation in Acorenone Levels

Abstract: Examination of the foliage oils of 25 specimens of Prumnopitys ferruginea identified ten sesquiterpene hydrocarbons (δ-elemene, α-cubebene, α-copaene, β-cubebene, germacrene-D, β-selinene, bicyclogermacrene, germacrene-A, δ-cadinene and γ-cadinene), the rare sesquiterpene ketone, acorenone, seven diterpene hydrocarbons (rimuene, beyerene, pimaradiene, sandaracopimaradiene, phyllocladene, kaurene and abietatriene) and a diterpene alcohol (Sβ-hydroxyisopimarene). Terpene levels were highly variable. β-Elemene, cis-calamenene and cadina-1,4-diene were detected as artefacts of aging of extracts. Some of the components showed antimicrobial activities against Bacillus subtilis and Trichophyton mentagrophytes, and cytotoxic activity against monkey kidney cells.

Asymmetric Dihydroxylation of Linalool, Nerolidol, and Citronellyl Acetate. Enantioselective Synthesis of (3S,6S)-Tetrahydro-2,2,6- trimethyl-6-vinyl-2H-pyran-3-ol.

Abstract: The asymmetric Sharpless' dihydroxylation of linalool, citronellyl acetate and nerolidol was investigated. High diastereo-, enantio- and positional selectivity was observed for the first two terpenes. A highly diastereo- and enantioselective synthesis of (3S,6S)-tetrahydro- 2,2,6-trimethyl- 6-vinyl-2H -pyran-3-ol is described.

Terpenoid Analysis of the Normal, Damaged Needle and Pinecone in Pinus densiflora

Abstract: To analyze terpene components, the essentail oil were extracted with steam distillation method from normal needle, damaged needle and pinecone of Pinus densiflora. The extracted essential oil was analyzed by gas chromatography and gas chromatography-mass spectroscopy. The results were summarized as follows; 1. Normal needles involve 43 kinds of terpene components, but damaged needles contained only 29 kinds. The most abundant components of normal and damaged needles were respectable -pinene and caryophyllene oxide. -pinene content in normal meedles amounted to 15.99 percents and caryophyllene oxide in damaged was 8.15 percents. 2. Pinecone showed 23 kinds of terpene components and among them the most abundant component was -phellandrene, of which content showed 19.31 percents. 3. In normal needles, excluding -pinene, the contents of 8 kinds of other monoterpenes, reached to 48 percents of the total terpenes, 4. In damaged needles, excluding -pinene, the contents of 4 kinds of other monoterpenes, reached to 11 percents of the total terpenes. 5. In pinecone, excluding camphene, the contents of 6 kinds of other monoterpenes, reached to 58 percents of the total terpenes.

Addition reaction of (+)-limonene, 2-pinene, and 2 (10)-pinene with C1∼C4 alcohols in the presence of synthetic zeolites

Abstract: Reactions of monoterpene hydrocarbons with alcohols (C 1 ∼C 4 ) were carried out in the presence of synthetic zeolites. The addition of (+)-limonene, 2-pinene, and 2 (10)-pinene to alcohols gave the corresponding terpenyl ethers as the major products. Some reaction products could be used as perfume bases

Isolation, Structural Elucidation and Structure-Activity Studies of Natural Products From Regional Plants of the Asteraceae.

Abstract: In a biochemical systematic study of the plant family Asteraceae combined with a search for bioactive natural products, the isolation and structural elucidation of secondary metabolites from seven plant species is reported. Investigation of the roots of Solidago canadensis provided six known and one new clerodane diterpenes related to kolavenic acid and five known matricaria ester-type polyacetylenes. The roots and aerial parts of Solidago mgosa afforded the known diterpenes kolavenol, hardwickiic acid, (-)-kaur-16-en-19-oic acid, (-t-)-manool, (+)-3(3-hydroxymanool, manoyl oxide and e/?f-abietic acid and the new labdane diterpene, (+)-18-tigloyloxymanool, plus four new t77f-abietane diterpenes. The isolation of two new and eight known eudesmane-type sesquiterpene cinnamates, and benzyl 2,6-dimethoxybenzoate from the roots of Brintonia discoidea (syn. Solidago discoidea) is reported. The roots of Chrysoma pauciflosculosa (syn. Solidago pauciflosculosa) provided the known polyacetylenes cis.cisand cis.trans-matricaria esters, a mixture of two isomeric epoxides of matricaria ester, and two known triterpenes, epifriedelinol and friedelin. In addition, the ubiquitous 2,6-dimethoxybenzoquinone and a new benzotropolone were found. The roots of Erigeron philadelphicus afforded, besides the above four polyacetylenes, two isomeric matricaria lactones. The roots of giant ragweed (.Ambrosia trifida ) afforded thiarubrine B and its related thiophene, as well as a new l,2-dithia-3,5-cyclohexadiene derivative, 3-(pent-3-yn-l-ynyl)-6-(3,4-epoxy-but-lynyl)-l,2-dithiacyclohexa-3,5-diene. The stems of A. trifida gave, besides (3-cubebene and a-l’arnesene, two carotane-type sesquiterpenes, the known lasidiol angelate ( la angeloyloxycarotol) and the new la-(2'-melhylbutyroyloxy)-carotol, plus 2,6dimethoxybenzoquinone and hexadecanal. The aerial parts of Liatris ohlingerae afforded five known and two new heliangolide-lype sesquiterpene lactones related to liscunditrin and four known triterpenes, taraxasterol, pseudo-taraxasterol and their acetates. The detailed structure elucidation using spectroscopic methods and chemical transformations is described. In order to demonstrate structure-activity relationships, a series of chemical transformations on sesquiterpene lactones were performed. Epoxidation of coslunolide yielded 1,10-epoxycostunolide, parthenolide, and the cyclization products santamarin, reynosin, magnolialide and a 1,4-epoxyeudesmenolide. Reduction of sanlamarin afforded 11,13-dihydrosantarnarin and an eudesmen-triol, while reduction of reynosin provided 11,13-dihydroreynosin and two eudesman-triols. The acidcatalyzed transformation of dihydroparthenolide in methanol afforded two guaianolide derivatives. These sesquiterpenes were tested against Mycobacterium tuberculosis and M. avium and the structure-activity relationships among sesquiterpene lactones are discussed. Polyacetylenes from S. canadensis, C. pauciflosculosa and E. ph iladelph icus also exhibited significant activity against these two strains of mycobacteria.

First Synthesis of 9‐Demethyl‐14‐carboxyretinoic Acid.

Abstract: A short synthesis of 9-demethyl-14-carboxyretinoic acid from β-ionone via 9-demethyl-β-ionylideneacetaldehyde is reported (48% overall yield).

The Terpenoids of Maytenus boaria MOL. (Celastraceae).

Abstract: The known triterpenoids β-amyrin (= olean-12-en-3β-ol; 22), lupeol (= lup-20(29)-en-3β-ol; 17), betulin (= lup-20(29)-ene-3β,28-diol; 18), lup-20(29)-ene-3β,30-diol (20), oleanolic acid (= 3β-hydroxyolean-12-en-28-oic acid; 21), and betulonic acid (= 3-oxolup-20(29)-en-28-oic acid; 19), together with epicatechol (= cis-2-(3,4-dihydroxyphenyl)-3,4-dihydro-2H-1-benzopyran-3,5,7-triol; 23), 5′-O-methylgallocatechol (= trans-2-(3,4-dihydroxy-5-methoxyphenyl)-3,4-dihydro-2H-1-benzopyran-3,5,7-triol; 24), and 4-hydroxybenzaldehyde were isolated from the aerial parts of Maytenus boaria (MOL.). Additonally, the eight 4,C4-dihydro-β-agarofuran sesquiterpenoids 1–8, one of them a diol with a (4R)-configuration, and compound 9 were present in the extract. The structures of these compounds were established by spectroscopic and chemical means.

New Monoterpene‐Substituted Dihydrochalcones from Piper aduncum.

Abstract: Five New unusual monoterpene-substituted dihydrochalcones, the adunctins A–E (1″S)-1-{2′-hydroxy-4′-methoxy-6′-[4″-methyl-1″-(1‴-methylethyl)cyclohex-3″ -en-1″ -yloxy]phenyl}-3-phenylpropan-1-one (1), (5aR*,8R*,9aR*)-3-phenyl-1-[5′,8′,9′,9′a-tetrahydro-3′-hydroxy-1′-methoxy-8′-(1″-methylethyl)-5′-a-methyldibenzo-[b,d]furan-4′-yl]propan-1-one (2), (2′R*,4″S*)-1-{6′-hydroxy-4′-methoxy-4″-(1‴-methylethyl)spiro[benzo[b]-furan-2′(3′H),1″ -cyclohex-2″ -en]-7′-yl}-3-phenylpropan-1-one (3), (2′R*,4″R*)-1-{6′-hydroxy-4′-methylethyl-4″-(1‴-methylethyl)spiro[benzo[b]furan-2′(3′H),1″-cyclohex-2″-en]-7′-yl}-3-phenypropan-1-one (4), and (5′aR*,6′S*, 9′R*,9′aS*)-1-[5′a,6′,7′,8′,9′a-hexahydro-3′,6′-methoxy-6′-methyl-9′-(1″-methylethyl)dibenzo[b,d]-furan-4′-yl]-3-phenylpropan-1-one (5) were isolated from the leaves of Piper aduncum (Piperaceae) by preparative liquid chromatography. In addition, (−)-methyllindaretin (6), trans-phytol, and α-tocopherol ( = vitamin E) were also isolated and identified. The structures were elucidated by spectroscopic methods, including 1D- and 2D-NMR spectroscopy as well as single-crystal X-ray diffraction analysis. The antibacterial and cytotoxic potentials of the isolates were also investigated.