Pyridocoumarin, aristolactam and aporphine alkaloids from the Australian rainforest plant Goniothalamus australis

► The aerial parts of Goniothalamus australis were chemically investigated. ► Two pyridocoumarin alkaloids were isolated along with 8 known natural products. ► A biogenetic pathway for goniothalines A and B is proposed. ► All compounds were tested for antimalarial activity using Plasmodium falciparum (3D7). ► Sauristolactam and (−)-anonaine displayed IC50 values of 9 and 7 μM, respectively.