- Structural determination of nootkatol, a new sesquiterpene isolated from Alpinia oxyphylla Miquel possessing calcium-antagonistic activity
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Nootkatol, a new sesquiterpene possessing calcium-antagonistic activity, was isolated from Alpinia oxyphylla Miquel and characterized as (2R,4R,5S,7R)-eremophil-1(10),11-dien-2-ol.
- Shoji,Umeyama,Asakawa,Takemoto,Nomoto,Ohizumi
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- Insecticidal sesquiterpene from Alpinia oxyphylla against Drosophila melanogaster
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In the course of screening for novel naturally occurring insecticides from Chinese crude drugs, an MeOH extract of Alpinia oxyphylla was found to possess insecticidal activity against larvae of Drosophila melanogaster Meigen. From the extract, an insecticidal compound was isolated by bioassay-guided fractionation and identified as nootkatone (1) by GC, GC-MS, and 1H and 13C NMR spectroscopy. In bioassays for insecticidal activity, I showed an LC50 value of 11.5 μmol/mL of diet against larvae of D. melanogaster and an LD50 value of 96 μg/adult against adults. Epinootkatol (1A), however, showed slight insecticidal activity in both assays, indicating that the carbonyl group at the 2-position in I was the important function for enhanced activity of 1.
- Miyazawa,Nakamura,Ishikawa
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- +-Nootkatone derivative
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The invention discloses a preparation method for +-nootkatone derivative. The present invention uses the +-nootkatone derivative extracted from cedar leaves as the main material, a chemical compound II is obtained after the restoration through sodium borohydride, the chemical compound II reacts to obtain a chemical compound III and a chemical compound IV through the decomposition of enzymatic dynamics, or decomposes through dynamic kinetics to obtain a chemical compound III with more than 90% yield, a chemical compound V is obtained after hydrolyzing the chemical compound III. The present invention turns the latent chiral ketone group in +-nootkatone into a chirality hydroxy center, and splits further; the present invention has the characteristics of being simple in operation, being high in product yield and with good optics purity.
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Paragraph 0010; 0016
(2017/08/27)
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- Synthesis of sesquiterpene-inspired derivatives designed for covalent binding and their inhibition of the NF-κB pathway
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A significant portion of bioactive secondary metabolites are endowed with reactive functionalities that can engage in covalent interactions with their target. Sesquiterpene lactones in particular are rich in Michael acceptors that react with cysteines. Several polycyclic scaffolds derived from total synthesis or readily available polycyclic terpenes were used as the starting point in the synthesis of a library aiming to project mildly reactive functionalities (Michael acceptors or chloroacetates) with diverse geometries. Screening of the library for inhibition of the NF-κB pathway revealed several potent inhibitors that are chemically readily accessible.
- Duplan, Vincent,Serba, Christelle,Garcia, Jose,Valot, Gaelle,Barluenga, Sofia,Hoerle, Melanie,Cuendet, Muriel,Winssinger, Nicolas
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supporting information
p. 370 - 375
(2014/01/06)
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- Biotransformation of the sesquiterpene (+)-valencene by cytochrome P450cam and P450BM-3
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The sesquiterpenoids are a large class of naturally occurring compounds with biological functions and desirable properties. Oxidation of the sesquiterpene (+)-valencene by wild type and mutants of P450cam from Pseudomonas putida, and of P450BM-3 from Bacillus megaterium, have been investigated as a potential route to (+)-nootkatone, a fine fragrance. Wild type P450cam did not oxidise (+)-valencene but the mutants showed activities up to 9.8 nmol (nmol P450)-1 min-1, with (+)-trans-nootkatol and (+)-nootkatone constituting >85% of the products. Wild type P450BM-3 and mutants had higher activities (up to 43 min-1) than P450cam but were much less selective. Of the many products, cis- and trans-(+)-nootkatol, (+)-nootkatone, cis-(+)-valencene-1,10-epoxide, trans-(+)-nootkaton-9-ol, and (+)-nootkatone-13S,14-epoxide were isolated from whole-cell reactions and characterised. The selectivity patterns suggest that (+)-valencene has one binding orientation in P450cam but multiple orientations in P450 BM-3.
- Sowden, Rebecca J.,Yasmin, Samina,Rees, Nicholas H.,Bell, Stephen G.,Wong, Luet-Lok
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- Highly efficient production of nootkatone, the grapefruit aroma from valencene, by biotransformation
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Nootkatone (2), the most important and expensive aromatic of grapefruit, decreases the somatic fat ratio, and thus its demand is increasing in the cosmetic and fiber sectors. A sesquiterpene hydrocarbon, (+)-valencene (1), which is cheaply obtained from Valencia orange, was biotransformed by the green algae Chlorella species and fungi such as Mucor species, Botryosphaeria dothidea, and Botryodiplodia theobromae to afford nootkatone (2) in high yield.
- Furusawa, Mai,Hashimoto, Toshihiro,Noma, Yoshiaki,Asakawa, Yoshinori
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p. 1513 - 1514
(2007/10/03)
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- Biotransformation of citrus aromatics nootkatone and valencene by microorganisms
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Biotransformations of the sesquiterpene ketone nootkatone (1) from the crude drug Alpiniae Fructus and grapefruit oil, and the sesquiterpene hydrocarbon valencene (2) from Valencia orange oil were carried out with microorganisms such as Aspergillus niger, Botryosphaeria dothidea, and Fusarium culmorum to afford structurally interesting metabolites. Their stereostructures were established by a combination of high-resolution NMR spectral and X-ray crystallographic analysis and chemical reaction. Metabolic pathways of compounds 1 and 2 by A. niger are proposed.
- Furusawa, Mai,Hashimoto, Toshihiro,Noma, Yoshiaki,Asakawa, Yoshinori
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p. 1423 - 1429
(2007/10/03)
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- Hydroxylation of sesquiterpenes by enzymes from chicory (Cichorium intybus L.) roots
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A microsomal enzyme preparation of chicory roots catalyses the hydroxylation of various sesquiterpene olefins in the presence of NADPH. Most of these hydroxylations take place at an isopropenyl or isopropylidene group. The number of products obtained from any of the substrates is confined to one or, in a few cases, two sesquiterpene alcohols. In addition, the conversion of (+)-valencene into nootkatone through β-nootkatol was observed. The involvement of (+)-germacrene A hydroxylase (a cytochrome P450 enzyme) and other enzymes of sesquiterpene lactone biosynthesis in these reactions is discussed.
- De Kraker, Jan-Willem,Schurink, Marloes,Franssen, Maurice C. R.,K?nig, Wilfried A.,De Groot, Aede,Bouwmeester, Harro J.
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p. 409 - 418
(2007/10/03)
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- The Rearrangement of Allylic Hydroperoxides Derived from (+)-Valencene
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(+)-Valencene (I) reacts with triplet oxygen to give 84 percent of the secondary β-hydroperoxyde (II) and 15 percent of the α-hydroperoxide (III); reaction with singlet oxygen gives principally (ca. 80 percent) the tertiary β-hydroperoxide (IV).This undergoes a Schenck rearrangement to give suprafacially the β-hydroperoxide (II) by a non-dissociative mechanism which does not involve exchange of oxygen in an atmosphere of 18O2.The hydroperoxide (II) then undergoes a slower Smith epimerization to the α-hydroperoxide (III) by a dissociative mechanism which involves a substantial (> 55 percent) exchange.
- Davies, Alwyn G.,Davison, Ian G. E.
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p. 825 - 830
(2007/10/02)
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