Drimanes

Bond formation between C-2 and C-7 as well as C-6 and C-11 of famesane formally leads to the drimane basic skeleton of sesquiterpenes The accepted numbering system is derived from decalin and not from famesane. The parent hydrocarbon 5a,8a,9p,10p-drimane with irans-decalin as core stracture occurs in paraffin oil. 

A simple drimane-type sesquiterpene alcohol, (—)-drimenol (297) which is the direct cyclization product of farnesol, has been isolated from Bazzania trilobata (149). Albicanol (298), a double bond isomer of (297), was isolated from Diplophyllum species its structure and stereochemistry were established on the basis of the LIS-values in H-NMR spectrum, the formation of the same drimanol, on hydrogenation of (297) and (298) and the observation that acid-catalyzed isomerization of (297) and (298) gave the same mixture of products (281). 

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E. Graf, M. Alexa, Planta Med. 1985, 428 [14-(umbelliferon-7-0-yl)driman-3a,8a-diol]. 

Heterocycles in synthesis of drimane sesquiterpenoids from labdane diterpenoids 97IZV896. 

Hashimoto, T., Tori, M. and Asakawa, Y. 1989. Drimane-type sesquiterpenoids from the liverwort Makinoa crispata. Phytochemistry 28 3377-3381. 

Sesquiterpenoids possessing the drimane skeleton (22) exhibit an impressive series of biological properties. Recently, all aspects relative to occurrence [76], biological activity [76], insect antifeedant properties [77] and synthesis [78] of these terpenoids have been exhaustively reviewed. 

The structure of polyalthenol (17), a metabolite of the African plant Polyalthia oliveri, has been determined by analysis of its n.m.r. spectra. It has been suggested that the rearranged bicyclofarnesane structure of this compound is produced by 1,2-methyl shift of a drimane-type intermediate. 

Ozonolysis of dehydroabietic acid has been used to give keto-esters such as (68) which have been converted into sesquiterpenoid drimane derivatives. An... 

Sacculatal (155) and its C-9 epimer, isosacculatal, are two diterpenoid dialdehydes which contribute to the pungent odour of the liverwort, Trichocoleopsis sacculata. Their structures bear a resemblance to the sesquiterpenoid drimanes. A diterpenoid analogue of the cadinene group is found in the structure of dihy-droxyserrulatic acid (156), from Eremophila serrulata (Myoporaceae). 

The isoprenoids contribute most to the list of structural similarities in the sea and on land. They range from common classes in both ecosystems, such as drimane sesquiterpenes, to rare classes in the sea, such as the trichothecenes (Chart 8.3.11). The similarity in marine and terrestrial polyether triterpenes (Chart 8.3.12) may be seen as convergence toward chemically favored structures, starting from squalene as a biosynthetic precursor. Similar conclusions may apply to polycyclic triterpenes. 

Manguro, L.O.A. et al., Flavonol and drimane-type seqiterpene glycosides of Warburgia stuhl-martnii leaves. Phytochemistry, 63, 497, 2003. 

Fukuyama, Y., Sato, T., Asakawa, Y., and Takemoto, T., A potent cytotoxic Warburganal and related drimane-type sesquiterpenoids from Polygonum hydropiper, Phytochemistry, 21, 2895, 1982. 

Mamanulhaquinone (1) is a combination of a sesquiterpene and a quinone. Its skeleton, with both terpene and quinone or hy-droquinone portions, is not unusual for a natural product derived from a sponge.2 An example is avarol (2). containing a hydroqui-none ring and the terpene skeleton of drimane.3... 

The Hawaiian sponge Hyrtios sp. from Oahu has furnished 21-chloropuupehe-nol (430), while the same sponge from Maui contains molokinenone (431) (619). The absolute configuration of these drimane-phenolic metabolites has been assigned as shown based on that of puupehenone (620). The South Georgia Island soft coral Alcyonium paessleri produces several novel illudalane sesquiterpenoids, including the chlorinated alcyopterosins A (432), D (433), K (434), and L (435) (621). 

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