<jats:p>The principal alkaloid of Balfourodendron riedelianum (Rutaceae) has been isolated and identified as (+)-ribaline (1b). The heartwood also contains minor amounts of (�)-ribaline and of two new alkaloids, identified as (+)-ribalinidine (2b) and (+)-2-(1'-hydroxy-1'-methylethyl)-2,3-dihydrofuro-[2,3-b]quinolin-6-ol [(+)-riedelianine] (4) by spectroscopic and X-ray crystallographic measurements.