| abstract |
The invention relates to a compound which has affinity with amyloid, shows sufficiently rapid clearance from normal tissues and is suppressed in toxicity such as mutagenicity, and also relates to a low-toxic diagnostic agent for Alzheimer's disease containing the compound. The compound is represented by the following formula (1) or a salt thereof: n nwherein A 1 , A 2 , A 3 and A 4 independently represent a carbon or a nitrogen, andn nR 3 is a group represented by the following formula:n n nwherein R 1 is a radioactive halogen substituent; m is an integer of 0 to 4; and n is an integer of 0 or 1, provided that at least one of A 1 , A 2 , A 3 and A 4 represents a carbon, and R 3 binds to a carbon represented by A 1 , A 2 , A 3 or A 4 . |