Cadinenes

The main components of Salvia mirzayanii were Linalool, Linalyl acetate, a-Tei pinyl acetate, 5-Cadinene, Spathulenol, Cubenol and a-Cadinol. The extraction yield, based on hydrodistillatin was 2.2% (v/w), and based on the SFE varied in the range of 0.65-10.59% (v/w) under different conditions. 

The oil contains about 60 per eeiit. of sesquiterpenes and 10 per cent, of seaqoiterpene alcohols. The principal sesqnileipcne ia probably cadinene, as indicated hy the following figures in comparison with those for eodinene obtained fvom oil of cade —... 

The oil oontains a-pi tictic,/ -piucnc, aud cadinene, a compound which has not previously baau recorded as ocenrring iu lurpeuiiuo oila. 

They delected a-plnene, -pineue, mviceuc, a sevquileqjeue which is eillier cadinene, or is easily couveiied into cadinene hydrochloride, aud a sesquitcrpeue alcohol, cadinol, of the formula C,.H. 50, Cadinol forms a hydrochloride melting at ll" to llii". 

Cadinene owes its name to its occuiTence in considerable quantity in oil of cade—which, of course, is not a true essential oil, but the product of destructive distillation. It is found in numerous essential oils, including those of patchouli, savin, galbanum, camphor, cedar wood. West Indian santal, juniper, and many others. Cadinene is best prepared as follows —... 

The fraction of oil of cade boiling at 260° to 280° is converted into cadinene dihydrochloride by saturating its solution in dry ether with dry hydrochloric acid gas. The hydrochloride is separated, dried, and leorystallised, and the hydrochloric acid removed by heating it with aniline or with sodium acetate in glacial acetic acid. The liberated cadinene is rectified in a current of steam. Cadinene from oil of cade is highly laevo-rotatory, the dextro-rotatory variety being obtained from Atlas cedar oil and West Indian sandalwood oil. 

The purest specimens of cadinene prepared have the following characters —... 

Lepeschkine prefers the use of sodium ethylate for the regeneration of the sesquiterpene, and gives the following figures for pure cadinene. so produced —... 

Cadinene yields a beautiful colour reaction when a few drops are dissolved in chloroform and shaken with a few drops of concentrated sulphuric acid. The liquid turns dark green, passing to blue and be-ooiuing red on warming. If acetic acid be used instead of sulphuric acid, the blue colour is more marked. 

Cadinene forms a well-defined crystalline dihydrochloride, C15H24.2HC1. In order to prepare it most successfully the fraction of oil of cade boiling between 260° and 280°, as mentioned above, is dissolved in twice its volume of dry ether, and saturated with dry hydro-ohloric acid gas. The mixture is allowed to stand for several days and... 

Cadinene dihydrobromide, C,5H24.2HBr, is obtained by shaking cad-ine dissolved in acetic acid with fuming hydrobromic acid. It forms white needles melting at 124° to 125°, and having a specific rotation — 36 13°. The dihydriodide, C15H24.2HI, prepared in a similar manner, melts at 105° to 106° and has a specific rotation - 48°. 

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

It does not yield a solid nitrosochloride, nor a nitrosite, hut it yields A crystalline hydrochloride, melting at 117° to 118°, which is identical with cadinene hydrochloride. Semmier considers copaene to have the iormula—... 

Highly uMtr-diastereofacial selective cycloaddition of isoprene (2) with 4-isopropyl-2-cyclohexenone allowed a short regiocontrolled and stereocon-trolled synthesis [13] of jS-cadinene and (y2-cadinene, Scheme 3.3). High anti-diastereofacial selectivity also occurs in the Diels-Alder reaction of optically active cyclohexenones 6-9 (Figure 3.2), readily available from the chiral pool, with open chain dienes [14-16]. Their cycloadducts are valuable intermediates in the synthesis of optically active sesquiterpenes in view of the easy conversion of the gem-dimethylcyclopropane and gem-dimethylcyclobutane in a variety of substituents. 

Resins older than 40 000 years are considered to be fossil resins. The fossilization of resins begins with polymerisation and forms ambers and copals. Most of the ambers are derived from components of diterpenoid resins with a labdanoid structure other ambers are based on polymers of sesquiterpene hydrocarbons such as cadinene, and may include triterpenoids less common ambers from phenolic resins derive from polymers of styrene. Figure 1.4 shows the skeletal structures of the components which make up the polymers occurring in fossil resins [141]. 

B.G.K. Van Aarssen, H.C. Cox, P. Hoogendoorn, and J.W. De Leeuw, A Cadinene Biopolymer Present in Fossil and Extant Dammar Resins as a Source for Cadinanes and Bicadinanes in Crude Oils from South East Asia, Geochim. Cosmochim. Acta, 54, 3021 3031 (1990). 

The volatile extract obtained from galbanum was principally composed of a-pinene (1), p-pinene (4), fenchyl acetate (30), y-cadinene (66), guaiol (77) and <7,v-guai-9-en-1 l-ol... 

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