Fifteen metabolites were isolated from the mycelium and culture filtrate of a strain of Aspergillus fumigatus which existed in the gastrointestinal tract of the saltwater fish Pseudolabrus japonicus. Among them, TR-2, fumitremorgin C and gliotoxin exhibited significant cytotoxicity against the cultured P-388 lymphocytic leukemia cells. Analysis of long range ^1H-^<13>C COSY and other spectral data for the five new metabolites[FQ-A(1),-B(2),-C(3),-D(4)and -E(5)], exhibiting marginal or moderate cytotoxicity, allowed assignment of their structures containing quinazolone and indoline moieties. The absolute stereostructure of 3 was determined on the basis of X-ray crystallographic analysis as well as of the production of L-(+)-alanine by its acidic hydroloysis. The stereochemistry of the other metabolites was established by deriving 1 and 5, from 3 and other chemical behavior.
