1-phenyl-4-exo-pentyl-2,3,5,6,11-pentaoxabicyclo[5.3.1]undecane

5-oxo-5-phenylpentanal

3,6-diphenyl-1,2,4,5-tetraoxane

trans-3,6-di-p-tolyl-1,2,4,5-tetroxan