Bis-Nor-diterpene

Bavoso A, Cafieri F, De Napoli L, Di Blasio B, Fattomsso E, Pavone V, Santacroce C (1987) Isolation and Structure Determination of Norsphaerol, a Bis-nor-Diterpene from the Red Alga Sphaerococcus coronopifolius. Gazz Chim Ital 117 87... 

To these four diterpenic skeletons is added that of nor-sphaerane, which is actually a bis-nor-diterpene because it only contains 18 carbon atoms, and the two recently discovered carbon skeletons of sphaeroane and that of coronone (Smyrniotopoulos, Vagias, and Roussis, 2009 Smymiotopoulos et al., 2010a). 

Bavoso, F A., Cafieri, F., De Napoli, L., Di Balso, B., Fattorusso, E., Pavone, V, and Santacroce, C. (1987) Isolation and structure determination of norsphaerol, a bis-nor-diterpene from the red alga Sphaerococcus coronopijblius. Gazz. Chim. Ital., 117,87-89. 

Several species of Sargassum, and Cystophora, contain derivatives of farnesylacetone (bis-nor-diterpenes) that have insecticidal properties, which might prevent the setting of larvae on the thallus (Kubo, Matsumoto, and Ichikawa, 1985). 

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