POLYODONINE, A PREFURANIC LABDANE DITERPENE FROM MARRUBIUM POLYDON

The new prefuranic labdane diterpene 9 alpha,13R;15,16-diepoxy-12-oxo- labd-14-en-19,6 beta-olide (polyodonine) has been isolated from the ae rial parts of Marrubium polydon. The known 3-O-(beta-D-glucopyranosyl) -3 beta-hydroxystigmast-5-ene and the flavone glucosides [beta-D-(6-O- p-coumaroyl)-glucopyranosyl]-apigenin and -D-(3,6-di-O-p-coumaroyl)-gl ucopyranosyl]-apigenin were also obtained from the same source. The st ructure of polydonine has ;been determined primarily on the basis of N MR spectroscopy.