Your request was penicillen which is probably a typo from penicillin.
penicillen -
Traditional English :: penicillin
penicillen - n. any of various antibiotics produced naturally by moulds of the genus Penicillium, or synthetically, and able to prevent the growth of certain disease-causing bacteria. [mod.L Penicillium genus name f. L penicillum: see PENCIL]