The hydroxylamine nortryptoquivaline (2) and the three secondary amines deoxytryptoquivaline (3), deoxynortryptoquivaline (4), and deoxynortryptoquivalone (8) were found to be toxic metabolites of Aspergillus clavatus, accompanied by the previously described tremor-producing agents tryptoquivaline (1) and nortryptoquivalone (7). The weakly basic secondary amines 3, 4, and 8 were oxidized to the corresponding hydroxylamines 1, 2, and 7 with m-chloroperbenzoic acid. The structures of these new metabolites were elucidated by spectral data (ultraviolet, infrared, nuclear magnetic resonance, high-resolution mass spectrometry, circular dichroism) and chemical transformations (acetylation, oxidation). All four new metabolites are toxic, none exhibit activity against Bacillus megaterium, while xanthocillin-X dimethyl ether (a known metabolite isolated from the same strain) shows antibacterial activity at 125 μg/ml or higher.