An imidazole derivative represented by one of formulas (1), wherein R.sub.1, R.sub.2 represents hydrogen atom, lower alkyl, aryl, aralkyl group, or R.sub.1 and R.sub.2 cooperate to represent alkylene, alkylidene, arylalkylidene group, R.sub.3 representing hydrogen atom, lower alkyl or alkanoyl group, or aralkyl or arylcarbonyl group, wherein at least one of A and B represents a group represented by formula (2), wherein m represents an integer 1-4, R.sub.4 representing nitrogen-containing aromatic ring that may be substituted by lower alkyl, alkoxy or alkanoyl group, or phenyl group represented by formula (3), R.sub.5, R.sub.6 representing hydrogen atom, lower alkyl or alkenyl group, or lower alkanoyl or arylcarbonyl group which may be substituted by a halogen atom, R.sub.7 representing hydrogen or halogen atom, hydroxyl or nitro group, or lower alkyl or alkoxy group, wherein the other of A and B represents oxygen or sulfur atom, hydroxyl, mercapto, alkylthio, alkenylthio or aralkylthio group, or group represented by the formula (2), ##STR1##