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A convenient synthesis of β-bisabolene, the component of the essential oil of lemon, lime, bergamot, and so on is described. The bisabolene was synthesized starting from methyl vinyl ketone and isoprene via 1- (4-methyl-3-cyclohexenyl) -1-ethanone N, N-dimethylhydrazone in five steps.

A new sesquiterpene alcohol, 12-hydroxy-E-gamma-bisabolene, is reported from an undescribed Caribbean sea whip of the genus Pseudopterogorgia. The structure of this new alcohol was established based upon spectral analyses and through chemical interconversions.

The aerial parts of Stevia salicifolia afforded two new bisabolene type sesquiterpenes. The structures were elucidated by spectroscopic, chemical transformations and correlation with 15-acetoxy bisabol-1-one.

It has been found that d-limonene is the principle constituent of the oil obtained by distilling Lemon Pondelosa peel. The percentage yield of the crude oil from the peel is 0.45%. The presence of an aldehyde with the empirical formula C10H14O (about 3% of the crude oil) and bisabolene (15% of the oil) was confirmed in the present work.

Gas chromatographic analysis revealed the qualitative composition of the essential oil from Australiangrown ginger to be similar to that of oils from other areas. The major constituents are a group of sesquiterpene hydrocarbons based on the bisabolene carbon skeleton. These compounds are accompanied by a number of monoterpene hydrocarbons and other substances. However, of particular interest, is the presence of a relatively high proportion of geranial and neral. These compounds are believed to invest Australian-grown ginger oil with a distinctive ‘citrus-like’ aroma.

In der ersten Arbeit wird die erste stereospezifische Synthese zu E-y- Bisabolen beschrieben.

Stereoselective reduction of the appropriate α-diphenylphosphinoyl ketone or addition of the lithium derivative of an alkyl diphenylphosphine oxide to an aldehyde or a ketone gives Horner-Wittig intermediates and hence the title compounds.

The sesquiterpenes farnesol, caryophyllene oxide, and 2,10-bisaboladien-1-one (patent #9602748) and the monoterpenes citronellol and geraniol were tested for settling inhibition and chronic effects on the aphidMyzus persicae by means of an improved leaf-disk assay. Of these compounds, geraniol, famesol, and the natural bisabolene significantly inhibit settling in choice tests. Furthermore, application of the bisabolene to intactCapsicum annuum leaves did not cause phytotoxicity, but did affect the insects' probing behavior by decreasing the probing activity and the number of intracellular punctures. Both compounds significantly decreased offspring production. Of the compounds tested, the natural product bisabolene could be a promising lead for future development of aphid control agents.

A simple one-flask synthesis of Z -γ-bisabolene (1) from the acyclic acetylene 2 is described.

The aerial parts of Oldenburgia arbuscula gave desacylcynaropicrin and three bisabolene derivatives while from Pleiotaxis rugosa in addition to janerin and 19-desoxyjanerin further guaianolides were isolated, including a new one. The chemistry of the Oldenburgia species supports its placement in the Mutisieae, subtribe Gochnatiinae, but that of Pleiotaxis may indicate that this genus is better placed in the Cynareae.

From the aerial parts of Stevia amambayensis in addition to known compounds three new sesquiterpene lactones, a grazielic acid derivative and two melampolides were isolated. The roots gave two new bisabolene derivatives.

The structures of the bisabolene derivatives yingzhaosu C (3) and D (4) have been determined by spectroscopic analysis in combination with chemical degradation.

Experiments with intact callus cultures of Andrographis paniculata and a derived cell-free system indicated that (a) the biosynthesised γ-bisabolene has the Z-configuration (3); (b) the biosynthetic intermediate is 2-cis, 6-trans-(1)- and not 2-cis,6-cis-(2)-farnesol pyrophosphate; (c) in paniculide B (5) the ring carbon derived from C-2 of mevalonate is anti to the side chain.