1-ethyl-2-methyl-[1,3,2]diazaborinane

1,3-diethyl-2-methyl-1,3,2-diazaboracycloheptane

1,2,3,4,5,6-hexamethyl-1,2,4,5,3,6-tetrazadiborinane

1,2,4,5-tetramethyl-3,6-diphenyltetraazadiborane