1,2,3,8,9,9a-hexahydroquinolizin-4-one

3-methyl-1-azabicyclo<4.3.0>non-2-en-9-one

2-甲基-5-氧代八氢-3-吲嗪甲醛

2-bromo-7-methylxanthen-9-one

1-(4-methoxyphenyl)-3-methylideneazetidin-2-one