Biologically active diterpenoids

If there is already a chiral centre in the molecule that has already been controlled by asymmetric synthesis, the AE reaction will ignore it if it is far enough away. Yamada s synthesis10 of the biologically active diterpenoid 45 illustrates this and demonstrates control when nucleophiles attack an unsymmetrical epoxide. Preliminary disconnections with a Diels-Alder in mind took the chemists back to the diol 48. 

BIOLOGICALLY ACTIVE DITERPENOIDS FROM SCOP ARIA DULCIS L. (SCROPHULARIACEAE)... 

The articles contained in this volume include the interaction of alkaloids with neuroreceptors and ion channels, anthracyclines suited for antibody-directed enzyme prodrug therapy and metabolites from soilborne fungi. Several articles are concerned with bioactive natural products from marine sources. The other areas covered include natural products with polyene amide structures, potential hypoglycemic agents, biological activity of essential oils, bioactive saponins and biologically active diterpenoids. 

Fujita, T., Y. Takeda, and T. Shingu Longikaurin A and B New, Biologically Active Diterpenoids from Rabdosia longituba. Chem. Commun. 1980, 205. 

All of these structures are central to a wide variety of natural products found both in plants and in animals. For example, cem-brene is a pheromone of termites casbene occurs in castor beans Ricinus communis, Euphorbiaceae) as an antifungal substance and is a precursor of other biologically active diterpenoids, such as phorbol (see 8-25, later) of the same plant family. Many species of the Euphorbiaceae family are regarded as toxic because their... 

Ochi, M., Yamada, K, Shirase, K., and Kotsuki, H. (1992a) Litophynins I and J, two new biologically active diterpenoids from the soft coral Litophyton sp. Chem. Lett., 155-158. 

Ochi, M Kataoka, K, Tatsukawa, A., Kotsuki, H., and Shibata, K (1993b) Acalydgorgins A, B, and C three new biologically active diterpenoids from the gorgonian Acalycigorgia sp. Heterocycles, 36, 41-44. 

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