Sesquiterpenes definition

Cadinene is a bicyclic sesquiterpene, whose constitution is not definitely understood. 

The above considerations indicate the complex nature of the hydrocarbons known as caryophyllene. For practical purposes, however, the compounds indicated are obtained of practically definite melting-points, and, in spite of the complicated isomerism existing amongst most of them, are useful for identification of the sesquiterpene or mixture of sesquiterpenes, occurring naturally and known as caryophyllene . 

The similarity between humulene and caryophyllene had not escaped Chapman s notice at the time that he isolated humulene, but as he was nnable to prepare a hydrate, which is one of the easiest of the caryophyllene derivatives to obtain in a pure state, he concluded that the sesquiterpene was not identical with caryophyllene. Eecent work by fiemmler does not tend to establish the identity of the two sesquiterpenes, and unless and until further evidence to the contrary is forthcoming, humvdene may be regarded as a definite chemical individual. 

A sesquiterpene has been isolated from the essential oil of Cannabis Indica. This may fairly be considered a definite body, as it has been isolated by many different observers and described by them at different times. Valenta first mentions it. Vignolo describes it as a mobile liquid boiling at 256°, of specific gravity -897 at 15°, and slightly laevo-rotatory. Wood, Spivey, and Easterfield give the boiling-point as 258° to 259°, the specific gravity as -898 at 18°, and the rotation as - 8-6°. 

The next group of alcoholic bodies to be studied are those which, although open-chaini alcohols, show considerable tendency to easily pass into closed-chain compounds, so that they occupy a definite position of their own, midway between the ordinary aliphatic series and the closed-chain series. The principal members of this important group are geraniol, nerol, linalol, and citronellol, together with the so-called aliphatic sesquiterpene alcohols, farnesol and nerolidol. 

Every effort has been made to include all known naturally occurring marine sesquiterpene/quinones as of September 1992. While compounds 9 0 to 93 appear not to satisfy the criteria of the survey, they are in fact aromatic ring contracted analogues. Likewise, although compounds 97 to 108 have received recognition in the literature as polyketides, in the absence of any definitive biosynthetic evidence to the contrary it is the contention of this author that they be considered as... 

As expected, Pd catalysed hydrogenation of the C3-C4 double bond of lactone 16.15 (Scheme 7) afforded the dihydroderivative 16.17 in which the C-3 methyl group was trans to H-2 (94). Comparison of the NMR data of compound 16.5, readily prepared from 16.17, with those of natural lactone 16.6 (Scheme 6) definitely proved the stereostructure of the latter sesquiterpene (94). Compound 16.6 was also synthesized from 5-lactaranolide 11.28 according to the reaction sequence shown in Scheme 6, which is a nice example of a general strategy for moving the carbonyl group of lactaranolides from C-5 to C-13 (94). 

Definition Mixt. of hydrocarbons distilled from certain plants and trees such as pine and citrus consists of terpenes, sesquiterpenes, diterpenes, polyterpenes... 

Definition Volatile oil from wood of Juniperus oxycedrus L. chief constituent is cadinene, a sesquiterpene... 

Synonyms Caryophyllene (-)-trans-Caryophyllene 8-Methylene-4,11,1 l-(trimethyl) bicycle (7.2.0) undec-4-ene trans-(1R,9S)-8-Methylene-4,11,11 -trimethylbicycio [7.2.0] undec-4-ene 4,11,11-Trimethyl-8-methylene, bicycle [7.2.0] unclec-4-ene Definition A mix of sesquiterpenes occurring in many essential oils (clove oil, lavender oil, cinnamon leaves, copaiba balsam)... 

Definition Volatile oil obtained from root of Sassafras officinale, contg. about 80% safrol, plus eugenol, pinene, phellandrene, sesquiterpene, d-camphor... 

Definition Volatile oil from leaves and tops of Lavanduia spica or L. iatifoiia, contg. about 35% eucalyptol, and camphor, linalool, borneol, terpineol, d-camphene, sesquiterpene... 

Our kno edge of the chemistry of this oil is chiefly due to-Bondiardat, who showed that it contained pinene and cineol (euca-lyptol). Later, he proved the presence of camphor, linalol, borneol, and esmphene. Terpineol and geraniol are also present in small quantities. Btobably a sesquiterpene also exists in this oil, but its presence has not yet been definitely proved. The similarity of the odour of this oil to-tme lavoider and rosemary is easily explained when one considers that... 

He has identified the following compounds in the oil cineol, limonene, palmitic and myristic acid in traces, 5 per cent, of a phenol not definitely identified, 2-bomeol, 2-camphor, and a sesquiterpene and a sesquiterpene alcohol. The phenolic body present is probably phloro-glucintrimethyl ether. 

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