| abstract |
Following formula (1) Here, Z is the following formula And n is an integer of 1 to 3, and when n is 2 or 3, Z may be the same as or different from each other, provided that when n is 1, Z is —CH. When n is 2 or 3, the plurality of Zs are not composed only of —CH 2 —, R 1 is an electron-withdrawing group having a Hammett number σ p greater than 0, and R 1 If 1 there are a plurality, the plurality of R 1 may be the same or different, X, and Y are each independently oxygen atom or = NR 2,, however, X and Y are both at the same time oxygen Never be an atom, The chromene compound which shows the double peak property which has the frame | skeleton shown by. |