The present invention offers compounds or their salts expressed by formula (I)(inthe formula, X indicates an alkyl group, or the like； Y indicates an alkylgroup； Zindicates a respectively independent nitro group, or the like； n indicates anyinteger from0 to 3； A indicates carbon atom, or the like, and hydrogen atom is bondedthereto in thecase where the carbon atom is not substituted with Z； D indicates oxygen atom,or thelike； W indicates hydrogen atom, or the like； R1 and R2 indicate respectivelyindependenthydrogen atoms, or the like； R1 and R2 may be bonded, and may form aheterocycletogether with the nitrogen atom between R1 and R2).(see formula I)
