Isofenchyl alcohol

A terpene yielding isofenchyl alcohol on hydration, which Wallach considers to be one of the fenchenes, was artificially prepared by converting nopinone into a hydroxy ester by means of bromoacetic ester and zinc-dust. The hydroxy ester is dehydrated by potassium bisulphate, and so yields an unsaturated ester, which on saponification yields an acid from which the terpene results by distillation. This fenchene has the following characters —... 

Bertram and Helle some years ago prepared a fenchene, which they termed isofenchene, by splitting off water from isofenchyl alcohol. L-d-fenchene prepared from Z-fenchone in a similar manner was found to have an optical rotation - 29°. 

By hydration with acetic and sulphuric acids, isofenchyl alcohol is form, and this can be oxidised to isofenchone. 

When the terpene a-fenchene (isopinene) is hydrated by means of acetic and sulphuric acids, it yields an isomer of fenchyl alcohol, which is known as isofenchyl alcohol (q.v.), and which on oxidation yields iso-fenchone, as fenchyl alcohol yields fenchone. The two ketones, fenchone and isofenchone, are sharply differentiated by isofenchone yielding iso-fenchocamphoric acid, Cj Hj O, on oxidation with potassium permanganate, which is not the case with fenchone. According to Aschan,i the hydrocarbon found in turpentine oil, and known as /9-pinolene (or cyclo-fenchene—as he now proposes to name it), when hydrated in the usual manner, yields both fenchyl and isofenchyl alcohols, which on oxidation yield the ketones fenchone and isofenchone. According to Aschan the relationships of these bodies are expressed by the following formulae —... 

Pregnane-3 (a), 17-diol-20-one74 Zero-Isofenchyl alcohol... 

Succinic Ethyl a-methylbutyrate Isofenchyl alcohol 2-Pentanal Methyl sulfide... 

Immunopolysaccharides, 21-25 Indole, 36, 65 Indoxyl, 65 Insulin, 31 Isoborneol, 78 Isobutyl alcohol, 37 Isobutysaldehyde, 38 Isocodeine, dihydro-, 69 Isofenchyl alcohol, 78 Isomenthone, 73 Isomorphine, 69 Isopentyl alcohol, 37 Isopropyl alcohol, 37 Isovaleraldehyde, 38... 

The fenchane structure appears to be stable in vivo. Both 1-fenchyl (CXXI) and -isofenchyl (CXXII) alcohols are excreted by rabbits as the corresponding glucuronosides (142). 

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