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Terpenoids, oxidation

Baum, R. H., Gunsalus, I. C. (1962). Mono and bicyclic terpenoid oxidation and assimilation by a soil diphtheroid. Bact. Proc., 108 (abstract, P31). [Pg.78]

The same author studied also the antinociceptive properties in animal experiments after oral administration of 1,8-cineole, a terpenoid oxide in many EOs. By pretreatment of mice with naloxone the antinociceptive effect of this bicyclic ether was not inverted in the formalin test (Santos et al., 2000). [Pg.243]

Santos et al. (2000) investigated the anti-inflammatory activity of 1,8-cineole, a terpenoid oxide present in many plant EOs. Inflammation could be reduced in some animal models, that is, paw edema induced by carrageenin and cotton pellet-induced granuloma. This effect was caused at an oral dose range of 100 00 mg/kg. The authors suggest a potentially beneficial use in therapy as an anti-inflammatory and analgesic agent. [Pg.247]

Santos FA, Rao VS (2000) Antiinflammatory and antinociceptive effects of 1,8-cineole a terpenoid oxide present in many plant essential oils. Phytother Res 14 240-244... [Pg.2689]

Open-chain 1,5-polyenes (e.g. squalene) and some oxygenated derivatives are the biochemical precursors of cyclic terpenoids (e.g. steroids, carotenoids). The enzymic cyclization of squalene 2,3-oxide, which has one chiral carbon atom, to produce lanosterol introduces seven chiral centres in one totally stereoselective reaction. As a result, organic chemists have tried to ascertain, whether squalene or related olefinic systems could be induced to undergo similar stereoselective cyclizations in the absence of enzymes (W.S. Johnson, 1968, 1976). [Pg.90]

Since GAs as diterpenes share many intermediates in the biosynthetic steps leading to other terpenoids, eg, cytokinins, ABA, sterols, and carotenoids, inhibitors of the mevalonate (MVA) pathway of terpene synthesis also inhibit GA synthesis (57). Biosynthesis of GAs progresses in three stages, ie, formation of / Akaurene from MVA, oxidation of /-kaurene to GA 2" hyde, and further oxidation of the GA22-aldehyde to form the different GAs more than 70 different GAs have been identified. [Pg.47]

Subsequent cyclizations, dehydrogenations, oxidations, etc., lead to the individual naturally occurring carotenoids, but little is known about the biochemistry of the many interesting final structural modifications that give rise to the hundreds of diverse natural carotenoids. The carotenoids are isoprenoid compounds and are biosynthesised by a branch of the great isoprenoid pathway from the basic C5-terpenoid precursor, isopentenyl diphosphate (IPP). The entire biosynthesis takes place in the chloroplasts (in green tissues) or chromoplasts (in yellow to red tissues). [Pg.60]

Supercritical fluid extraction — During the past two decades, important progress was registered in the extraction of bioactive phytochemicals from plant or food matrices. Most of the work in this area focused on non-polar compounds (terpenoid flavors, hydrocarbons, carotenes) where a supercritical (SFE) method with CO2 offered high extraction efficiencies. Co-solvent systems combining CO2 with one or more modifiers extended the utility of the SFE-CO2 system to polar and even ionic compounds, e.g., supercritical water to extract polar compounds. This last technique claims the additional advantage of combining extraction and destruction of contaminants via the supercritical water oxidation process."... [Pg.310]

Cannabinidiol (CBND, 2.18) and cannabinol (2.19) are oxidation products of CBD and A9-THC formed by aromatization of the terpenoid ring. For the dehydrogenation of THC a radical mechanism including polyhydroxylated intermediates is suggested [10,11]. CBN is not the sole oxidation product of A9-THC. Our own studies at THC-Pharm on the stability of A9-THC have shown that only about 15% of lost A9-THC is recovered as CBN. [Pg.7]

Direct oxidation of A9-THC at position C-11 involves mainly an isomerization to A8-THC another opportimity in the synthesis of A9-THC-metabolites is the pretreatment of terpenoid synthons by introduction of protective groups, e.g., 1,3-dithiane (6.1 in Fig. 6) followed by the condensation with olivetol (6.2) [76]. The formed product is a protected derivate... [Pg.22]

Very simple compounds such as alkyl-substituted tetrahydrofurans can be dehydrogenated by chlorosulfonic acid or by oleum, these reagents having some capacity for oxidation, and furylium ions are produced (Section III,B), but the technique has not been exploited synthetically.19 The presence of an easily eliminated group helps indeed, the terpenoid furan solidagenone might well be an artefact formed during isolation from an unstable hydrofuran... [Pg.170]

Bacteriological sulfur, 23 577-578 Bacteriophages, 3 135 12 474 in fermentation, 11 46 Bacteriorhodopsin, 20 826, 840 photochromic material, 6 603 Bacteriosins, 12 76. See also Bacteriocins Bacteriostatic water, 18 714 Bacterium lactis, 11 7 Baculovirus expression system, 5 346 Baddeleyite, 21 489 26 623-624 colorants for ceramics, 7 346t Badische Anilin und Soda Fabrik (BASF) terpenoid manufacture process, 24 481 Baeyer-Villiger oxidation reactions, 14 592 chiral recognition by enzymes, 3 675 microbial, 16 401 Baffled shellside flow, 13 262 Baffles, in stirred tank geometries,... [Pg.84]

Terpenoids are susceptible to a number of alterations mediated by oxidation and reduction reactions. For example, the most abundant molecule in aged Pinus samples is dehydroabietic acid [Structure 7.10], a monoaromatic diterpenoid based on the abietane skeleton which occurs in fresh (bleed) resins only as a minor component. This molecule forms during the oxidative dehydrogenation of abietic acid, which predominates in rosins. Further atmospheric oxidation (autoxidation) leads to 7-oxodehydroabietic acid [Structure 7.11]. This molecule has been identified in many aged coniferous resins such as those used to line transport vessels in the Roman period (Heron and Pollard, 1988 Beck et al., 1989), in thinly spread resins used in paint media (Mills and White, 1994 172-174) and as a component of resin recovered from Egyptian mummy wrappings (Proefke and Rinehart, 1992). [Pg.242]

Another heterocyclization is presented by Panifilow et al. Cyclic acetals and ethers are obtained by electrochemical oxidation of the terpenoid alcohol linalool 57 in methanol containing alkaline and sodium methoxide as electrolyt [102]. Anodic oxidation of the C(6)-C 7) double bond of linalool leads to the radical cation 58. In addition to direct methoxylation of the radical cation an attack on the hydroxyl group takes place. After a second one-electron oxidation and following methoxylation the regioisomeric cyclic acetal and a subsequent 1,2-hydride shift, the cyclic acetal 60 and the cyclic ether 61 are finally formed in yields of 16 and 24%, respectively (Scheme 13). As shown by Utley and co-workers bicyclic lactones 65 and 66 can be synthesized by anodic oxidation... [Pg.87]

Terpenoid DBPs were investigated by Joll et al. [124] and Qi et al. [125]. The main ozonation product of 2-methylisobomeol was camphor, which was further oxidized to formaldehyde, acetaldehyde, propanal, buntanal, glyoxal, and methyl glyoxal [125]. Chlorination of p-carotene, retinol, p-ionone, and geranyl acetate resulted in the formation of THMs [124]. [Pg.117]

Py-FIMS results clearly reveal the existence of a thermally extractable, bitumen-like fraction which is chemically distinct from the remaining coal components. In lignite, several biomarker compounds were noticeable in the mobile phase components while bituminous coals contain various alkylsubstituted aromatic compounds in the mobile phase. Blind Canyon coal, which contains 11% resinite, exhibits mobile phase components believed to originate from terpenoid aromatization. Curie-point Py-LVMS results illustrate the importance of the oxidation status of coal for studying the mobile phase since mild air oxidation severely changes the structural characteristics of the thermally extractable mobile phase. [Pg.89]

Until the mid 1960 s the only plant cannabinoid whose structure was fully elucidated was cannabinol (CBN) — a constituent which actually may represent an oxidation artifact. However, on the basis of CBN, the main cannabinoid structure skeleton became known. Thus, cannabidiol (CBD), which had been independently isolated in pure form by Adams and by Todd, was correctly assumed to be, like CBN, a terpenoid derivative attached to olivetol. But its exact structure was not elucidated. The psychoactive components of cannabis were assumed to be related tricyclic derivatives. On the basis of the tentatively elucidated constituents, Todd suggested that the cannabinoids may be formed initially in the plant by condensation of a menthatriene with olivetol. [Pg.52]

Polyene cyclizations have been of substantial value in the synthesis of polycyclic natural products of the terpene type. These syntheses resemble the processes by which terpenoid and steroidal compounds are assembled in nature. The most dramatic example of biological synthesis of a polycyclic skeleton from a polyene intermediate is the conversion of squalene oxide to the steroid lanosterol. In the biological reaction, the enzyme presumably functions not only to induce the cationic cyclization but also to bind the substrate in a conformation corresponding to the stereochemistry of the polycyclic product.21... [Pg.601]

Cyclic ethers used as fragrances include a number of terpenoid compounds. Some of them, such as 1,4-cineole [470-67-7] and 1,8-cineole, occur in essential oils in significant quantities. Others are only minor components examples are rose oxide, nerol oxide [1786-08-9], and rose furan [15186-51-3], which contribute to the specific fragrance of rose oil. Caryophyllene oxide [1139-30-6], which has a woody,... [Pg.141]

The introduction of matrices to assist the laser desorption ionization (LDI) process has lead to the development of the so-called matrix-assisted LDI (MALDI). This technique has been applied to identify terpenoid varnishes and their oxidized products [46], Combined with enzymatic cleavage, MALDI has also been used in the identification of animal glue. [Pg.22]


See other pages where Terpenoids, oxidation is mentioned: [Pg.163]    [Pg.190]    [Pg.288]    [Pg.78]    [Pg.379]    [Pg.14]    [Pg.234]    [Pg.276]    [Pg.223]    [Pg.78]    [Pg.299]    [Pg.337]    [Pg.187]    [Pg.235]    [Pg.278]    [Pg.1003]    [Pg.158]    [Pg.170]    [Pg.168]    [Pg.169]    [Pg.105]    [Pg.194]    [Pg.80]    [Pg.485]    [Pg.81]    [Pg.679]    [Pg.150]    [Pg.396]    [Pg.481]   
See also in sourсe #XX -- [ Pg.143 ]




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