<jats:title>Abstract</jats:title><jats:p>Investigation of the root bark of <jats:italic>Magnolia kachirachirai</jats:italic> led to the isolation of a new sesquiterpene, kachirachirain (<jats:bold>1</jats:bold>), and a new aporphine alkaloid, kachirachiranine (<jats:bold>2</jats:bold>), together with 20 known compounds, of which dimethyl 4,4′‐methylenebis(4,1‐phenylene)diurethane (<jats:bold>3</jats:bold>) was isolated for the first time from a natural source. Their structures were elucidated by spectroscopic analysis.