Myrcene-3. -epoxide

Diazaquinones 68, 83a, and 90 have been shown to provide adducts with various isoprenoids, as exemplified by the /3-myrcene adduct 140 (87H193). The side-chain double bonds of these adducts can be functionalized by epoxidation with 3-chloroperoxybenzoic acid or via bromination with IV-bromosuccinimide to provide the corresponding derivatives 141 and 142, respectively (Scheme 34). 

S. Akutagawa and S. Otsuka, J. Amer. Chem. Soc., 1976, 98, 7420 the formula for isogeraniol lacks the 6,7-double bond and the diene minor product is named incorrectly. No experimental details are given for the hydrolysis of this myrcene-magnesium complex but the results contradict those reported by Cookson et al. who have extensively investigated its reactions with carbonyl compounds, epoxides, carbon dioxide, and acetonitrile. ... 

Epoxidations, carbene additions, etc. of 2,3-epoxycitral have been studied.209 A very detailed investigation of the dye-sensitized photoxidation of a-nerol (92) showed the formation of the diols (93) and (94) with no cyclized products.210 Allo-ocimene and myrcene on autoxidation in DMF or DMSO give an odd variety... 

H,14C]MVA was incorporated into la,2a,3p-trihydroxy-p-menthane by a Fusicoccum sp., and the labelling pattern suggested that p-menth-2-en-l-ol was generated from an a-terpinyl cation by a 1,3-hydride shift, followed by formation of the a-epoxide and cleavage.896 Ips beetles converted [2H]myrcene (the isotopically normal substrate being obtained in nature from Pinus spp.) into ipsdienol and... 

The epoxidation of terpenic substrates is of interest in the flavor and fragrance industry [55,56]. Terpenes are derivatives of isoprene, which has formula CsHg (2-methyl-frans-butadiene). There are tens of examples of terpenes, including limonene, a-pinene, geraniol, citronellol, myrcene, ocimene, camphene, a-terpin-eol, menthol, and isopugelol. Limonene is an abundant monoterpene extracted from citrus oil, which can be epoxidized to obtain fragrances, perfumes, and... 

The skeleton can be synthesized from myrcene (7) (brominative cyclization was mentioned in Vol. 4, p. 534, Ref. 583), either by reaction with benzenesulfenyl chloride (giving 719), or by epoxidation (to 720) before cyclizing with SnCl4 or trifluoroacetic acid. The cyclized products 721 (R = OCOCF3 or Cl, R = OH or SPh) were converted to the boll-weevil pheromone 722 (R... 

Qccurance and Identification. An early report of cotton volatile composition by Minyard et al. (44) involved steam distillation of large quantities of leaves and flowers. Major compounds identified included the monoterpenes a-pinene, B-pinene, myrcene, trans-B-ocimene, and limonene ( 4). Several other monoterpene hydrocarbons were also present in low concentration. Since that report, many other terpenes have been identified in cotton essential oil steam distillates and solvent extracts. These compounds include cyclic hydrocarbons such as bisabolene, caryophyllene, copaene and humulene (45-47), the cyclic epoxide caryophyllene oxide (45), cyclic alcohols such as bisabolol, spathulenol, and the aromatic compound... 

Dimethyl-7-methoxyoctan-2-ol is prepared by hydrochlorination of dihydro-myrcene, methoxylation of the resulting 2-chloro-2,6-dimethyl-7-octene, and epox-idation. The alcohol is obtained by hydrogenation of the epoxide in the presence of Raney nickel and triethylamine [53]. It is used in perfumery as a top note in high quality sandalwood compositions for cosmetics, toiletries, and soaps. 

Myrcene is the major constituent of the essential oils of Hamulus lupulus and Levisticum officinale (Bornscheuer et ah, 2014). After oral application, several metabolites in the urine of rabbits were identi ed whereby the formation of the two glycols may be due to the hydration of the corresponding epoxides formed as intermediates (Ishida et ah, 1981). The formation of uroterpenol may proceed via limonene, derived from myrcene in the acidic conditions of rabbit stomachs (Figure 9.21). 

P-Myrcene (302) was converted by common cutworm larvae, Spodoptera litura, to give myrcene-3,(10)-glycol (308) via myrcene-3,(10)-epoxide (307) (Figure 19,2) (Miyazawa et al, 1998),... 

P-Myrcene (302) was converted by common cutworm larvae, S. litura, to give myrcene-3, (10)-glycol (308) via myrcene-3,(10)-epoxide (307) (Miyazawa et al., 1998). Citronellene (309) was metabolized by cutworm S. litura to give 3,7-dimethyl-6-octene-l,2-diol (310) (Takechi and Miyazawa, 2005). Myrcene (302) is metabolized to two kinds of diols (303 and 304), myrcenol (305), and ocimene (306) (Seubert and Fass, 1964 Abraham et al., 1985). Citronellene (309) was metabolized to (310) by S. litura (Takeuchi and Miyazawa, 2005). 

The primary aromatic substances in beer are derived from raw materials (barley or hops) that confer the beer s typical odour and taste. Bitter acids of hops have a bitter taste (see Section 8.3.5.1.3), but hop cones also contain 0.3-1% m/m of terpenoids (60-80% of hop essential oil), which have a considerable influence on the smell of beer. The main components of aromatic hop oils are sesquiterpenic hydrocarbons in which a-humulene, P-caryophyllene and famesene dominate. The major monoter-penic hydrocarbon is myrcene. For example, the essential oil content of fine aromatic varieties, such as Saaz, is 0.8% m/m, of which 23% is myrcene, 20.5% a-humulene, 14% famesene 6% and P-caryophyUene. Significant components of the hop aroma in beer are mainly isomeric terpenoid monoepoxides resulting from autoxidation and diepoxides of a-humulene and fS-caryophyUene, but also other terpenoids. Important components of hops odour are also various alcohols (such as geraniol and hnalool), esters (ethyl 2-methylpropanoate, methyl 2-methylbutanoate, propyl 2-methylbutanoate and esters of terpenic alcohols, such as geranyl isobutanoate), hydrocarbons, aldehydes and ketones formed by oxidation of fatty acids, such as (3E,5Z)-undeca-l,3,5-triene, (Z)-hex-3-enal, nonanal, (Z)-octa-l,5-dien-3-one, their epoxides, such as ( )-4,5-epoxydec-2-enal and sulfur compounds. Other important components of hops are so-called polyphenols (condensed tannins) that influence the beer s taste and have antioxidant effects. Less important compounds are waxes and other hpids. Hop products, such as powder, pellets and extracts (by extraction with carbon... 

Essential oil components common to the aerial parts of E. pallida, E. purpurea, and E. angustifolia include bomeol, bornylace-tate, pentadeca-8-en-2-one, germacrene D, caryophyllene, caryophyllene epoxide, and palmitic acid. According to another report, the aerial parts contain P-myrcene, a- and P-pinene, limonene, camphene, tran -ocimene, 3-hexen-l-ol, and 2-methyl-4-pentenal. The same report lists dimethyl sulfide, 2- and 3-methylbutanal, 2-propanal, 2-methylpropa-nal, acetaldehyde, camphene, and limonene as the main volatile constituents of the roots, in addition to a-phellandrene that is present only in E. purpurea and E. angustifolia roots. ... 

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