| abstract |
A compound represented by the following formula (1), or a salt thereof: in which all of A1, A2, A3 and A4 represent a carbon, R 1 is a radioactive halogen substituent, R 2 is a group selected from the group which consists of hydrogen, hydroxyl group, methoxy group, carboxyl group, amino group, N-methylamino group, N group, N-dimethylamino and cyano group, and p is an integer from 0 to 2. |