Occurrence in Wood and Bark

Although none of the investigations of the sterols of bark and wood have utilized techniques such as H-NMR, C-NMR, or appropriate capillary GLC, which 

Fischer et al. (23) have reported an especially good study (Table 8.2.1) of the structure and amounts of sterols from the wood of various conifers. 

Botanical Common Campesterol 24-Methyl- Sitosterol 5a-Sito- 

Chamaecyparis lawso-niana Port-Orford-cedar 14 65 11 

Plants in the other conifer family (Taxaceae) seem to be of the main line just as the Pinaceae are. The heartwood of species of the tribe Thxeae (Taxus baccata, T cuspidata, T floridana, and T, brevifolia) are reported (20) to contain sitosterol (25) and campesterol (14 in the Zl -3)ff-ol series) (presumably with its C-24 epimer). The other tribe (Podocarpae) of this family, which includes the important genus Podocarpus, may therefore also be main line. The leaves and bark of Podocarpus lambertius actually yielded an incompletely identified sample of sitosterol (7). 

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