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The lipophile extract of Lonchocarpus nicou roots afforded the new pyranochalcone 3-O-methylabyssinone A as well as the new rotenoids 7′-hydroxytephrosin, and 7′-nor-6′-oxo-2′,3′-dehydrorotenone, both compounds occurring with the known 7′-hydroxydeguelin and 7′-nor-6′-oxo-2′,3′-dehydro-12aβ-hydroxyrotenone. Furthermore, two rotenoid epoxides previously reported as resulting from the direct oxidative conversion of rotenone and 12aβ-hydroxyrotenone, respectively, were isolated for the first time from a plant source. All the structures were established on the basis of UV, MS, and NMR data.

A lipophile extract of Lonchocarpus nicou roots afforded two likely O -substituted isomers of the known tubaic acids. Spectroscopic analysis assigned to the former, named (−)-rotoic acid, the new 4-(2,3-dihydro-6,7-dimethoxychromon-3-oxy) tubaic acid structure which differs from (−)-deguoic acid, the latter, by the β-tubaic acid part. Biogenetically, the two compounds could be considered as resulting from the parent rotenone and deguelin, respectively, by oxidative ring-C cleavage.

Lonchocarpus nicou roots lipophile extract yielded, among isoflavonoids, two coumaronochromones isomers. Spectroscopic analysis assigned the structure of nor-dehydrodeguelin to the former and (−)-nor-dehydrorotenone to the latter, the two products only differing by the cyclization of the C 5 side chain. Biogenetically, the two compounds could be considered as resulting either from cyclization of the corresponding 2′-hydroxyisoflavones and/or from oxidative ring-B contraction of the dehydrorotenoids parents.

3,5-Dimethoxyaniline was acetylated and found to be a key intermediate for the synthesis of a variety of biologically active aminoflavones and quinolones.