STRUCTURAL STUDIES OF BIOLOGICALLY INTERESTING NATURAL PRODUCTS

The structure of one of a series of four new anthracycline antitumor compounds isolated from Micromonospora peucetica was determined by a single crystal x-ray diffraction experiment to be 11-deoxydaunorubicin. This series of anthracyclines is important because it shows reduced cardiotoxicity, while maintaining the efficacy of the related daunorubicin series of anthracyclines.;The structure of a rare triterpene from the marine sponge Stelletta sp. was determined by a single crystal x-ray diffraction experiment. The structure possesses a tricyclic skeleton, with trans-syn-trans stereochemistry about the ring function, and a polyene system conjugated to an alpha-pyrone.;Structures for two new monoterpenes glycosides from the Chinese medicinal plant Paeonia lactiflora have been investigated. The first compound has been shown by single crystal x-ray diffraction methods to be (7)-(1S, 5R)-(beta)-pinen-10yl (beta)-vicianoside. A structure for the second compound is proposed, based on spectral analysis, to be a highly oxygenated pinane skeleton, related to paeoniflorin and albiflorin, which is linked to a glucopyranose through the C-1 and C-2 oxygens of the sugar.;An attempt was made to clarify the structure of leucogenenol, a compound first isolated by F. A. H. Rice from Pencillium gilmanii. Leucogenenol stimulates proliferation, differation and maturation of a wide spectrum of leukocytes and lymphocytes. Leucogenenol was isolated from bovine liver extract, and improvements and further purification steps were added to a published isolation scheme. Biological assaying of our leucogenenol material shows it to have greater activity than leucogenenol material isolated by Rice.