Farnesol acetate

This compound must arise from bromonium ion cyclization of the 6,7-bromohydrin of farnesol acetate. Hydrolysis of the acetate group in (47) and sequential treatment with phosphorus tribromide and water gave obtusenol (46). Other syntheses of marine sesquiterpenoids include those of pallescensin-E (48),30 furoventalene (49),81 and dactyloxene-B (50) and -C (51).32 The last mentioned established the absolute configurations of the two dactyloxenes. A second synthesis of ancistrofuran (53) and its C-2 epimer has been recorded starting from the lactone (52) which is derived from homogeranic acid (Scheme 3).33... 

The possibilities of 1-methylcyclobutene as an isoprene equivalent have again attracted attention. Reaction of methylcyclobutene with -3-hexene catalysed by tungsten hexachloride and tetramethyltin gave the metathesis product (319) in ca. 25 % yield as a mixture of isomers. In a similar reaction with geraniol acetate, small amounts of farnesol acetate were detected. 

Farnesal forms a semi-carbazone, which crystallises from acetic ether in fine flakes, which melt at 133° to 135°. This body is particularly useful for the identification of farnesol. 

Farnesol forms an acetate, farnesyl acetate, which is a nearly odourless oil, boiling at 169° to 170° at 10 mm. 

In order to establish the primary character of farnesol, farnesenic acid was prepared from farnesal oxime and the corresponding nitrile. Saponification of the farnesene-nitrile with caustic soda solution yields farnesenic acid and acetic acid, and also a ketone which was identified as a dihydropsewdoionone. The semi-carbazone melts between 95° and 96°. The dihydropmtdoionone from farnesene nitrile proved to be... 

The Asian elephant has farnesol, 4-ethylphenol and 4-methylphenol in its temporal gland secretion while the African elephant has only 4-methylphenol. Farnesol levels are inversely related to testosterone levels (Rasmussen and Perrin, 1999). Preovulatory female urine contains (Z)-7-dodecen-l-yl acetate (Rasmussen etal, 1996). 

Other components are acyclic aliphatic esters and terpenes, such as farnesol and farnesyl acetate [237-239a]. Ambrette seed oil is one of the most expensive essential oils and, thus, is used mainly in fine fragrances and in alcoholic beverages. FCT 1975 (13) p.705 [8015-62-1], [84455-19-6]. 

The first data about the bioconversion of farnesol date back to the sixties its degradation pathway is similar to that of geraniol and nerol. Seubert [139] showed that the degradation of farnesol by Pseudomonas citronellolis proceeds through the oxidation of C-l to give famesic acid, followed by carboxylation of the -methyl group. Subsequently, the 2,3-double bond of the dicarboxylic acid is hydrated to a 3-hydroxy acid which is then acted upon by a lyase resulting in the formation of a /Tketo acid and acetic acid. The /Tketo acid readily enters the fatty acid oxidation pathway [29]. 

Commercial production of vitamin K is by column chromatography of fish meal extracts. In biosynthesis, precursors include polyacetic acid (ring) acetate (side chain). Intermediates include dehydroquirric acid tring) farnesol (side chain). 

Schmialek (1963) obtained radioactive farnesol and famesal from silkworm moth treated with [2- ]-mevalonic acid. The experiments of Sridhara and Bhat (1965), Happ and Mainwald (1966), Karlson (1970), Meyer et al. (1970) also prove that isoprenoid biosynthesis in insects proceeds via mevalonic acid as intermediate product, i.e. it is analogous to the early stages of mammalian steroid biosynthesis prior to the formation of the sterane skeleton. Early intermediates include acetate (Schooley et al.. 1973), acetyl-CoA (Baker and Schooley, 1978), (3S)-HMG-CoA (Bergot et al., 1979) and (3/ )-mevalonate (Schooley et al., 1973 Lee et al., 1978 Feyereisen et al., 1981). 

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