Briareum polyanthes

The versatility of the enolone ester 27 is illustrated by a variety of synthetically useful addition reactions, e. g. with lithium alkyls, Grignard reagents and cyclopentadiene in a Diels-Alder type fashion (40, 48, 49), but, most notably, it could be utilized for straightforward syntheses of the marine natural products (-)-bissetone (28), a metabolite from the Gorgonian soft coral Briareum polyanthes (50), and (-)-palythazine (29), an unusual dipyranopyrazine isolated from the salt water invertebrate Palythoa tuberculosa (51). 

Briarellins are a class of eunicellin diterpenes isolated from the gorgonians Pachyclavularia violacea and Briareum polyanthes [88]. 

Briaranes are found in marine organisms including corals, represented by the brian-theines W and X from Briareum polyanthes. Brianthein X is reported to be an insecticide, while the closely related (-)-solenolide A isolated from Solenopodium species exhibits antiviral and antiinflammatory activities. These briarane lactones are usually referred to as erythrolides. 

Grode, S.H., T.R. James, and J.H. Cardellina II Brianthein Z, a New Polyfunctional Diterpene from the Gorgonian Briareum polyanthes. Tetrahedron Lett. 24, 691 (1983). 

Briareum polyanthes Terpenoids (diterpenes) Eu nicel 1 i n-type asbesti nane-type briarane-type Activity against pathogenic microbes of human infectious diseases [77]... 

Cronan, J.M., Daviau, T.R., Pannell, L.K., and Cardellina, J.H. (1995) Emmotene, from the gorgonian Briareum polyanthes, contains the first naturally occurring troras-bicyclo[5,l,2]octane. J. Org. Chem., 60, 6864-6865. 

Ospina, C.A. and Rodriguez, A.D. (2006) Bioactive compounds from the gorgonian Briareum polyanthes. Correction of the structures of four asbestinane-type diterpenes.y. Nat. Prod., 69,1721-1727. 

Briarellins J-P and polyanthellin A New eunicellin-based diterpenes from the gorgonian coral Briareum polyanthes and their antimalarial activity./. Nat. Prod., 66, 357-363. 

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