Oxidative transformations of cembrane diterpenoids. II. Cembra-2,7,11-triene-4,5-diols

Summary 1. The oxidation of cembrene with chromium trioxide in aqueous acetone forms, together with other compounds, the products of its hydroxylation at the C₄ double bond — cembra-2,-7,11-triene-4,5-diols epimeric at the C₄ double bond.2. On the basis of chemical and spectral characteristics, it has been established that these diols have the 4S, 5R and 4R, 5R configurations, respectively.Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Academy of Sciences of the USSR, and Novosibirsk State University. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 54–59, January–February, 1977.