The analgesic components were isolated from a Bornean medicinal plant, Tabernaemontana pauciflora Blume (syn. Ervatamia blumeana Mark gr.), and the major components were identified as coronaridine and 3-(2-oxopropyl)coronaridine. Four minor components were estimated to be 5R- and 5S-(2-oxopropyl)coronaridine, 3-(2-oxopropyl)voacangine and 3,3'-(oxopropyl)dicoronaridine, which might be produced during the isolation process. Voacangine was also isolated as a major component of T. pandacaqui Poir. Coronaridine and voacangine exhibited significant analgesic and hypothermic effects in mice at a dose of 25 mg/kg, p.o., while 3-(2-oxopropyl)coronaridine was less effective. The former two compounds also revealed a surface anesthesia.