P-Humulene

Ethyl alcohol n-Heptanal Ethyl proprionate a-P-Humulene... 

The major terpenoid components of cloves and hops are remarkable in that they contain highly strained medium sized rings. Four of the most important members of the family are shown in Figure 7.29. Of these, the most important are P-caryophyllene (7.137) and a-humulene (7.139). These are the most frequently encountered in essential oils and are often referred to simply as caryophyllene and humulene, respectively. For convenience, these shorter names will be used in this book. For example, a-humulene (7.139) has been found in hundreds of essential oils whereas there are reports of P-humulene (7.140) in only a few. Almost invariably, several members of the family will be found together in oils. For example, all oils which have been found to contain humulene (7.139) also contain caryophyllene (7.137) and isocaryophyllene (7.138). 

Ring closure of C-1 and C-11 of famesane, not only formally but also in biogenesis via famesyldiphosphate, produces the sesquiterpene skeleton of more than 30 naturally oeeurring humulanes Regioisomeric a- and p-humulene occur in the leaves... 

Ginseng herb oil (P. ginseng) has been reported to contain sesquiterpenes, including bicyclogermacrene, a- and P-panasinsenes, caryophyUene, a- and P-humulenes, a- and P-neoclovenes, P-famesene, and a-, P-, and y-selinenes. ... 

Martin et al. (1974) collected specimens from 22 locations throughout the range of H. courbaril and identified a number of sesquiterpenes including caryophyllene [173], humulene [174], selinene isomers [175 is P-selinene], and other related compounds (see Eig. 2.48 for compounds 173-175). Caryophyllene and two selinene... 

Sampling time 60 min extraction temperature 80°C. Monoterpenes a-pinene, p-myrcene, a-phellandreneand limonene sesquiterpenes a-cubebene, a-copaene, p-elemene, p-caryophyllene, a-humulene, y-muurolene, p-eudesmene and caryophyllene oxide diterpenes cembrene A and isoincensole acetate. 

The first observation is the similarity between the chemical compositions of both the Boswellia carteri and Boswellia sacra. For these three olibanum samples, a-pinene (2), (3-myrcene (8) and limonene (14) are the predominant monoterpenes. p-Caryophyllene (73) is the major sesquiterpene besides a-copaene (65), a-humulene (also called a-caryophyllene) (78) and caryophyllene oxide (95). The characteristic olibanum compounds isoincensole and isoincensole acetate (128) together with cembrene A (120) are the main diterpenes. 

Boswellia serrata olibanum has a chemical composition close to that of both the B. carteri and of B. sacra, but contains compounds that are absent in those from other Boswellia and could be used as markers methylchavicol (38), p-anisaldehyde (47), methyleugenol (70), isocaryophyllene (82), sesquiterpene 91, elemicin (92) and an unidentified diterpene (124) eluting between cembrene C (123) and verticilla-4(20),7,ll-triene (125). It is devoid of (5-caryophyllene (73), a-humulene (78), caryophyllene oxide (95) and bornyl acetate (50). 

Wie und in welcher Reihenfolge diese verwickelten Reaktionen ver-laufen, ist experimentell und theoretisch noch ungeklart. Sukh Dev (37) erhielt aus dem Humulen (a-Caryophyllen) durch Cyclisierung mit p-Toluolsulfonsaure ein Bicyclohumulen, das bei der Dehydrierung mit Palladiumkohle ebenfalls ein Azulen — wohl Guajazulen — bildete. 

Juniperus rigida Sieb. et Zucc. J. rigida Sieb. et Zucc. f. modesta (Nakai) Y. C. Chu Tu Soon (Juniper) (fruit) Alpha-pinene, myrcene, carene, limonene, p-cymene, beta-elemene, caryophyllene, humulene, bomeol, r-cadinene, terpinene, citronellol, anethole.48 Hemorrhage, treat hemoptysis, inflammation, kidney infection, arthritis joint infection. 

Zingiber zerumbet Smith Qiu Jiang (Ginger) (rhizome)55-60 3".4"-0-diacetylafzelin, zerumbone, zerumbone epoxide, curcuminoids diferuloylmethane, feruloyl-p-coumaroylmethane, di-p-coumaroylmethane, essential oils, alpha-humulene.192-193-195 These compounds are cytotoxic. A tonic, stimulant, depurative, to treat asthma, stomachache, antimicrobial properties. This plant plays an important role in masculine rituals and it makes women sterile. 

The 11-carbon ring of the humulyl carbocation may be retained, as in the formation of humulene (Figure 5.36), or modified to give the caryophyllyl cation containing a nine-membered ring fused to a four-membered ring, as in P-caryophyllene (Figure 5.36). Humulene is found... 

A new tricyclic hydrocarbon, senoxydene, which has been isolated from Senecio oxyodontus, has been assigned the structure (304) on the basis of its n.m.r. spectrum together with that of the corresponding epoxide.It is suggested that once again humulene could act as the precursor (Scheme 48) see, however, p. 104. 

A complete account of the experimental evidence leading to the structural elucidation of the first members (244a—d) of the capnellane group of sesquiterpenoids has been provided in a recent paper cf. Vol. 5, p. 70). These compounds (244a—d) are found in soft coral (Capnella imbricata) and it has been suggested that their biosynthesis involves cyclization of humulene followed by methyl migration from C-5 to C-4 [cf. (245)]. 

Composition Eugenol (65-85%), methyl eugenol, 1,8-cineole and numerous mono-and sesquiterpene hydrocarbons, e.g. myrcene, p-caryophyllene and humulene [230], The commercially available oils also derive from the leaves and possess a similar composition, whereas the content of methyl eugenol in most cases is higher in the berry oil [231, 232[. For further research results see [233[. 

Croton sylvaticus Hochst. The essential oil of semi-dried C. sylvaticus leaves (0.14%) contained mainly the sesquiterpenes p-caryophyllene oxide (35%) and a-humulen-1,2-epoxide (12%) (56). The aqueous extract of the stem bark of C. sylvaticus reduced exploratory activity, prolonged ether anesthesia, relaxed the muscles and had analgesic effects on mice (5 7). The plant is used for treatment of swellings caused by kwashiorkor, for tuberculosis and as a purgative (35). 

Plectranthus barbatus Andr. This species contains a wide range of mono-and sesquiterpenoids including humulene and P-caryophyllene, 5-selinene, bomeol, camphene, P -phellandrene, a-ionone and a-thujene (65). The leaves are used as a purgative and for stomachaches. Leaves are soaked in warm water and the water is used to bath babies with measles (35). 

Euphorbiaceae Croton sylvaticus Hoscht. Leaves SD 0.14 P-caryophyllene oxide, a-humulen-1,2-epoxide 56... 

Plectranthus barbatus Andr. humulene and P-caryophyllene, 5-selinene, borneol, camphene, p -phellandrene, a-ionone, a-thujene 65... 

Camphene, a- Rosemary plant, P-Pinene, Cineole, and spruce needles Camphor, Bomeol, Bomyl Acetate, Humulene Cinnamaldehyde, Cinnamon Coumarin, C15H24 Isomers Limonene, a- Orange peel P-Pinene, C15H24 Limonene, Menthol, Chewing gum Isomenthone, Carvone, Menthone, C15H24 45 0.90 300... 

Naya and Kotake, in an examination of Japanese hop oil, have isolated three humulane-type compounds, viz., humuladienone (161, R = Me), humulenone II (161,R = =CH2), and humulol (162), in addition to the tricyclic diol (163, R = OH), m.p. 207 °C. This diol has already been prepared in two different ways (a) Sutherland et treated humulene (164) with AT-bromosuccini-mide in aqueous acetone and converted the resultant bromohydrin (163, R = Br) to the diol (163, R = OH), m.p. 205—206 °C, by hydrolysis, (b) McKervey and Wright obtained the same diol, m.p. 201—203 °C, by acid-catalysed (20% sulphuric acid) rearrangement of humulene 1,2-epoxide (165), a known natural product. On the basis of these findings and the fact that both caryophyllene (166) and humulene can be derived from the above bromohydrin by two in vitro steps, McKervey and Wright postulated that humulene 1,2-epoxide may be involved in the biosynthesis of the tricyclic diol and caryophyllene. This postulate does not, however, readily accommodate the observed rotations of the relevant... 

Monoterpenes, on the other hand, possess particularly desirable flavor notes. Three of them, (3-myreene (A.45), limonene (A.46) and p-cymene (A.59) are common to coffee, cocoa and tea, and to numerous plant families (3-myrcene for example constitutes 63% of hop oils. It is worth remembering that they particularly contribute to the flavor of spices. In a study of the effluvia of fresh red coffee berries, Mathieu et al. (1996) identified, in two varieties of robusta, a series of mono- and sesquiterpenes, a blend also present in cold pressed oil from pommelos. In fact, the effluvia of red berries attracts the females of the coffee berry borer, a very important pest. Without giving a list of the hydrocarbons identified in this study, let us note that limonene is the most abundant of them, caryophyllene (4,11,11-trimethyl-8-methylenebicyclo[7.2.0]undec-4-ene), followed by humulene (2,6,6,9-tetramethylundeca-1,4,8-triene) and a-pinene (2,6,6-trimethylbicyclo[3.1.1]hept-2-ene), are rather important in two robusta... 

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