The structure of a novel antibiotic, epiderstatin, was determined as 4-[3-((Z)-3,5-dimethyl-2-oxopiperidin-6-ylidene)-2-oxopropyl]-2, 6-piperidinedione by spectroscopic analyses of 1H NMR, 13C NMR, 1H-1H correlation spectroscopy (COSY), 13C-1H COSY, heteronuclear multiple bond correlation spectroscopy, UV and IR spectra. The antibiotic belongs to the glutarimide antibiotics, however, the characteristic feature of epiderstatin is that it has a piperidone ring instead of a cyclohexanone ring.