The aerial parts of Boronia lanceolata yielded 10 4(1H)-quinolinone and 9(10H)-acridinone alkaloids. Six of these, 1,8-dihydroxy-9(10H)-acridinone, 1,8-dihydroxy-10-methyl-9(10H)-acridinone, 1,3,8-trihydroxy-10-methyl-9(10H)-acridinone, 1-acetoxymethyl-2,3-dimethyl-4(1H)-quinolinone, 1-acetoxymethyl-2-methyl-4(1H)-quinolinone and 2,3-dimethyl-4(1H)-quinolinone are novel. All alkaloids were identified by spectroscopic techniques, notably 2D heteronuclear NMR experiments. © 1993.