William A. Ayer

The sterpuric acids

Abstract The fungus Stereum purpureum , the cause of the so-called silver leaf disease, produces a new type of sesquiterpenoid when grown in liquid culture. The structures and reactions of sterpuric acid ( 1 ), methyl hydroxysterpurate ( 17 ), and methyl hydroxysterpurate ethylidene acetal ( 22 ) are reported. An X-ray crystallographic structure determination of sterpuric acid ( 1 ) is presented.

Metabolites of bird's nest fungi—VII: Bicyclofarnesane sesquiterpenes of mycocalia reticulata petch

Abstract The metabolites of the birds nest fungus Mycocalia reticulata Petch have been examined and the bicyclofarnesane sesquiterpenes 7-ketodihydrodrimenin (1), 7β-hydroxydihydrodrimenin (2a), and 6α,7β-di-hydroxydihydrodrimenin (3a) have been isolated. These compounds have not been obtained previously from natural sources, although 1 and 2a are known transformation products of other natural products. Compound 3a is new, and its structure was established by physical methods. The known triterpenoid glochidone (μ) and β-sitosterol were also isolated.

THE STERPURIC ACIDS: A NEW TYPE OF SESQUITERPENOID ††Dedicated to the memory of Professor R. B. Woodward. Presented in part at the 63rd Canadian Chemical Conference, Ottawa, June 1980. Abstracts, p. 120.

The fungus Stereum purpureum, the cause of the so–called silver leaf disease, produces a new type of sesquiterpenoid when grown in liquid culture. The structures and reactions of sterpuric acid (1), methyl hydroxysterpurate (17), and methyl hydroxysterpurate ethylidene acetal (22) are reported. An X–ray crystallographic structure determination of sterpuric acid (1) is presented.