Six new carotane sesquiterpenoids piltunines A-F (1-6) together with known compounds (7-9) were isolated from the marine-derived fungus Penicillium piltunense KMM 4668. Their structures were established using spectroscopic methods. The absolute configurations of 1-7 were determined based on circular dichroism (CD) and nuclear Overhauser spectroscopy (NOESY) data as well as biogenetic considerations. The cytotoxic activity of some of the isolated compounds and their effects on regulation of reactive oxygen species (ROS) and nitric oxide (NO) production in lipopolysaccharide-stimulated macrophages were examined.
