Investigation of the extractives of Neuoautanenia amboensis schinz with special reference tonuclear magnetic resonance studies on hydroxybenzofurans

Four new compounds were isolated from Neorautanenia amboensis, three minor isoflavavoids, the dhydrorotenoids DEHYDRODOLINEONE, NEBOENSINONE and NAMBINONE, and the isoflavone glycoside AMBONIN. In addition four known isoflavanoids, NEODULIN, NEOTENONE, PACHYRRHIZIN and DEHYDRONEOTENONE were also isolated from N. amboensis. This dissertation is concerned with: (i) The elucidation of the structures of the new compounds mentioned above by chemical and physical methods. (ii) Nuclear magnetic resonance studies on hydroxybenzofurans and related phenolic derivatives of natural isoflavanoids with special reference to the relation between anion shift and chemical structure. A summary is given [in the full text PDF summary] of the most important results which were obtained and which represent a contribution to our knowledge of the isoflavanoids and the physical methods used in their structural elucidations.