diethyl [4-(4-oxo-6-phenyl-4H-thiopyran-2-yl)phenyl]phosphonate

diethyl [4-(4-oxo-6-phenyl-4H-selenopyran-2yl)phenyl]phosphonate

4-(4-oxo-6-phenyl-4H-selenopyran-2-yl)phenylphosphonic acid

4-((2-(4-(diethoxyphosphoryl)phenyl)-6-phenyl-4H-thiopyran-4-ylidene)methyl)-2,6-diphenylselenopyrylium hexafluorophosphate