A composition useful as herbicides, germicides, and acaricides without showing toxicity to men and beasts as well as to fish and shellfishes containing as the active ingredient the compound represented by the general formula ##STR1## wherein R represents a lower alkyl group; R' represents a group shown by the formula ##STR2## (WHEREIN Y represents a halogen atom, an alkyl group, an alkoxy group, a nitro group, a methylthio group, or a trifluoromethyl group and n is an integer of 0 to 3); X represents an oxygen atom or a sulfur atom; and m is an integer of 3 to 6.