三氟乙酸酐

4-benzyl-1,2,4-dithiazolidine-3,5-dione

羰基硫

3-(4-nitro-phenyl)-2H-[1,2,4]oxadiazol-5-one

3-p-nitrophenyl-4,5-dihydro-1,2,4-thiadiazol-5-one