1αH,5αH-Tropan-3α-yl isovalerate is the principal alkaloid of the root-bark of Erythroxylum dekindtii; other new bases characterised are 1αH,5αH-tropan-3α-yl phenylacetate and 1αH,5αH-tropan-3α-yl 2-furoate. The root-bark also contains methylecgonidine, valeroidine, poroidine, isoporoidine, and tropine.