Itaconic acid derivatives and diketopiperazine from the marine-derived fungus Aspergillus aculeatus CRI322-03

► Three compounds were isolated from the fungus, Aspergillus aculeatus. ► New metabolites were pre-aurantiamine (1) and litaconic acid derivatives 4 and 5. ► Pre-aurantiamine (1), a diketopiperazine, might be a precursor of aurantiamine.