Naturally occurring cembranes from an Australian sarcophyton species

Naturally occurring cembranes 1-4 have been isolated from a Sarcophyton sp. These compounds have not previously been found to occur in nature but had been obtained as intermediates in a synthetic modification from tobacco. The absolute stereochemistries of 3 and 4 were determined. Compounds 1 and 2 inhibited the binding of [(3)H]8-cyclopentyl-1,3-dipropylxanthine to rat-brain adenosine A(1) receptors.