Propenone derivatives

The present invention relates to propenone derivatives represented by the following formula (I): wherein R represents substituted lower alkyl or YR (wherein Y represents S or O, and R represents substituted or unsubstituted lower alkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or a substituted or unsubstituted cyclic ether residue), R and R represent independently hydrogen, lower alkyl, or substituted or unsubstituted aralkyl, or R and R are combined to represent substituted or unsubstituted methylene or ethylene, R represents hydrogen, hydroxy, lower alkyl, substituted or unsubstituted aralkyl, lower alkoxy, substituted or unsubstituted aralkyloxy, or halogen, and X represents substituted or unsubstituted indolyl, or pharmaceutically acceptable salts thereof.