Two cytotoxic triphenylpyrrolo-oxazinones were isolated from a tunicate and their structures elucidated by spectral methods. Lukianol A (= 3,7,8-tris(4-hydroxyphenyl)pyrrolo[2,1-c][1,4]oxazin-1 (1H)-one; 1) had MIC of 1-mu-g/ml in KB cytotoxicity tests; MIC value for 2 was 100-mu-g/ml.