(4S)-4-hydroxy-4-methyloxan-2-one

4-甲基-5,6-二氢吡喃-2-酮

4-甲基-2H-吡喃-2,6(3h)-二酮

8-hydroxy-1-methoxy-3-methylanthracene-9,10-dione

4-methyl-4-trimethylsilyloxyoxane-2,6-dione