Rose furan

Of all these, probably P-phenethyl alcohol (2) comes closest to the odor of fresh rose petals however, mixing all these components does not reproduce the total fine character of the natural oil. It has been determined that a number of trace constituents representing less than 1% of the volatiles are critical to the development of the complete rose fragrance (10). These include cis- and trans-i.ose oxide (1), nerol oxide (12), rose furan (13), /)i7n7-menth-l-en-9-al (14), P-ionone (15), P-damascone (16), and P-damascenone (3). 

Cyclic ethers used as fragrances include a number of terpenoid compounds. Some of them, such as 1,4-cineole [470-67-7] and 1,8-cineole, occur in essential oils in significant quantities. Others are only minor components examples are rose oxide, nerol oxide [1786-08-9], and rose furan [15186-51-3], which contribute to the specific fragrance of rose oil. Caryophyllene oxide [1139-30-6], which has a woody,... 

Routes to furan monoterpenes from other monoterpenoids are well known, and the photooxygenation route from myrcene (7) to perillene (849) was discussed in Vol. 4 (p. 561). Using the aldehyde 863 led, by the same route ( 62, then ferrous ion) to perillenal (846). The simplest reported preparation of perillene (849) from a dimethyloctane monoterpenoid precursor is certainly the autoxidation of citral enol acetates (864), yielding 11% of a mixture of perillene (849) and rose furan (848) after passing air through a chloroform solution for 24 hours. 

There has been further study of the direct prenylation of 3-methylfuran (cf. Vol. 2, p. 161, Ref. 558 Vol. 4, p. 557, Ref. 724) using 3-chloro-3-methyl-l-butene or the corresponding trifluoroacetate and zinc halides or silver tri-fluoroacetate. Rose furan was indeed obtained, but was accompanied by the 2,4-disubstituted furan. 

Some tetrahydrofuran analogs to rose furan have been synthesized by Hoepfner and Weyerstahl, but none was as interesting a perfume as rose furan. " ... 

Some natural products containing a furan ring have an intense odour, e.g. 2-furylmethanethiol 27, a component of coffee aroma, rose furan 28, a component of rose oil, and menthofuran 29, which occurs in peppermint oil. The compounds 28 and 29 are reminiscent of terpenoid structures ... 

The furan ring is found in furoic acid (3.38). Some alkyl furan derivatives have value as odorants. Thus, rose furan (3.39) gives the characteristic odor of rose oil. Other derivatives have potent biological activity, such as beta-furyl isoamyl ketone (perilla ketone, 3.40), which causes pulmonary edema in animals grazing on plants containing this substance (such as Perilla Frutescens Britton). Ascorbic acid (the well-known Vitamin C), which when written as the enoUc form (3.42) is... 

Perillene, a monoterpenoid furan derived from p-myreene, is a eonstituent of the essential oil obtained from Perilla citridora (Labiatae) among other monoterpenes, it also occurs in the pheromones of some mites and acts as a defense pheromone of the ant Lasius fulginosus. The isomerie rose furan is a fragrant component of the oil of rose obtained from fresh flowers of Rosa damascena (Rosaceae). 3-(4-Methyl-3-pentenyl)thiophene and derived eyclic tri- and tetrasulfides (1,2,3-trithiepine and 1,2,3,4-tetrathiocine) are found in the oil of hops. 

A third monoterpene, rose furan, has been identified as the major constituent produced by the thrips Arrhenothrips ramakrishnae (2 ). Rose furan is accompanied by perillene and in addition, hexadecyl acetate is quantitatively significant. Two aromatic compounds, phenol and phenylacetaldehyde, are minor concomitants in the anal exudate. 

Perillene (141) was isolated from the essential oil of the leaves of Perilla citriodom Makino 314) as well as from the ant Lasius (Dendro-lasius) fuliginosus Latr. 487). On the other hand, rose furan (142) was isolated for the first time from rose oil 61). 

RAMP 160 Reboxetin 448 Ring analysis 15 Ring-chain tautomerism (tetrazole) 275 Ring formula index 16 Ring inversion see inversion Ring name index 16 Rose furan 78 Rotenone 341... 

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