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The structures of daljanelins A-C 1 , 3 and 5, the first pterocarpan-neoflavonoid oligomers, and of daljanelin D 6 a related isoflavonoid-neoflavonoid analogue from Dulbergiu nitidula were established by spectroscopic methods. The structure and stereochemistry of daljanelin C 5 were unambiguously confirmed by synthesis via introduction of an electrophilic C-1 fragment to a pterocarpan nucleus followed by anionic coupling of a C,C, precursor and the late introduction of the final C6 fragment by a Grignard reaction.Paper 4/06549B

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Different electron-rich dienophiles were combined with the imine obtained from 2,4-O-benzylidene-d-erythrose and p-anisidine furnishing enantiomerically pure tetrahydroquinolines, by inverse electron-demand [4π + 2π] cycloaddition. The imine was also reacted with 2-substituted electron-rich 1,3-butadienes giving the diastereomeric pure product, resulting from the normal electron demand cycloaddition. The facial selectivity of both processes is proposed on the basis of a 1,4-relationship between the hydroxyl group and the nitrogen atom in the chiral N-(p-methoxyphenyl)imine derivative.