Ah&r&-The structure of taondiol (1). a new aromatrc terpenoid compound isolated from the marine alga Taonia atomaria (Dyctiotaceae) is elucidated and its biogenesis discussed. 1 I'-Desoxy-taondiol methyl ether (7) has been synthesized.
In a preliminary communication* we reported the isolation from the marine alga Taonia atomaria of the tocopherol-like compound taondiol, for which we proposed structure 1 based on spectroscopic analyses, chemical transformations and biogenetic considerations.
The present paper details the chemistry and spectral properties of taondiol and its transformation products as well as the synthesis of the taondiol derivative 7.
RESULTS AND DISCUSSION
Analytical values and mass spectrometry fit for taondiol the_empirical formula C,,H,,O, (M+ at
m/e 412*292), m.p. 283-284", [oh, -76". In the IR it shows bands at 3540,3340, 1620, 1500,860 and 800 cm-r and in the UV at 298 nm. The PMR spectrum? (Table 1) exhibits two meta-coupled aromatic protons at 3.56 and 3.62, a singlet at 5.76 (I H, exchangeable with D,O) assigned to the phenolic hydroxyl proton, two broad signals at 6.8 (WIls = 14 Hz,>CHOH) and 7.40 (two benzyl protons), and two singlets at 7.89 (aromatic Me) and 8.86 (Me group on carbon bearing oxygen). In the upfield region appear four tertiary Me