1,3,7,9-tetra-tert-butyl-2,2,8,8-tetramethyl-5,10-di(benzoyl)1,3,5,7,9,10-hexaaza-2,8-disila-4,6-digermadispiro{3.1.3.1}decane
1,3,7,9-tetra-tert-butyl-2,2,8,8-tetramethyl-5,10-di(4-methyl-phenyl)1,3,5,7,9,10-hexaaza-2,8-disila-4,6-digermadispiro{3.1.3.1}decane
1,3-di(tert-butyl)-2,2-dimethyl-1,3,2,4-diazasilastannetidine-4-spiro-2'-1,3-di-p-tolyl-1,3,2,4-diazadistannetidine-4'-spiro-4''-{1,3-di(tert-butyl)-2,2-dimethyl-1,3,2,4-diazasilastannetidine}
1,3,7,9-Tetra-t-butyl-2,2,8,8-tetramethyl-5,10-di(p-tolyl)-1,3,5,7,9,10-hexaaza-4-germa-6-stanna-2,8-disiladispiro{3.1.3.1}decan
1,3-di-t-butyl-2,2-dimethyl-5,8-di(p-tolyl)-1,3,5,6,7,8-hexaaza-4-germa-2-silaspiro{3.4}oct-6-ene