6550-28-3 20-ethoxy-6,7,9,10,12,13-hexahydrodibenzo[d,p][1,3,6,9,12,15,2]hexaoxaphosphacycloheptadecine 20-oxide 33080-36-3 DIPYRIMIDO[4,5-D:4',5'-M][1,10,3,7,12,16]- DITHIATETRAAZACYCLOOCTADECINE-6,17(5H,10H)- DICARBOXALDEHYDE,11,16,21,22-TETRAHYDRO-8,- 19-BIS(2-HYDROXYETHYL)-2,7,13,18-TETRAMETHYL-