Podocarpus lactone

Recently we have extended the MS/MS studies of the Podocarpus lactones to include analysis employing reactive collisions with ethyl vinyl ether. Minor differences in structure led to different reactivities with the reagent (ref. 

New congeners of cytotoxic nor-diterpenoid dilactones in Podocarpus nagi two C19 lactones from seed extract. Hayashi, Y. Yuki, Y. Matsumoto, T. Sakan, T. Tetrahedron Lett. 1977,41,3637-3640. 

Plant growth inhibitory lactones from Podocarpus neriifolius. Structure of podolactone E. Galbraith, M.N. Horn, D.H.S. Sasse, J.M. Experientia 1972, 28, 253-254. 

Some chemical transformations of norditerpene lactones from Podocarpus sellowii. Brown, K.S. Sanchez, W.E. Tetrahedron Lett, 1974,8, 675-678. 

The structures of a number of norditerpenoid lactones from Podocarpus species have been revised as a result of some X-ray analyses. Inumakilactone A (46) has... 

Ketomanoyl oxide (17), which is readily obtained from Podocarpus species, has been converted into the 3-hydroxy-norlabdene acid (18), which is a useful triterpenoid synthon. A lactone (19), related to lagochilin, has been detected in Lagochilus hirsutissimus. The order of acetylation of the hydroxy-groups of lagochilin is C-15 > C-16 > C-18 > C-3." ... 

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