A proposed structure for schizocommunin (Z)-1(hydroxy) and its geometric isomer (E)-1(hydroxy), which exist in a keto form, has been synthesized. However, the spectroscopic data of (Z)-1(keto) and (E)-1(keto) were not consistent with those reported for natural schizocommunin. After reinvestigating the spectral data for natural schizocommunin, we synthesized the quinazolinone derivative (Z)-2 as a revised structure for schizocommunin. All of the spectral data of (Z)-2 were completely identical to those reported for natural schizocommunin. (Z)-2 showed moderate antiproliferative activity.