In this study, the crystal structures of the dispiroansa spermine derivatives of cyclotriphosphazene are characterised for the first time. The reaction of spiro-, gem-disubstituted cyclotriphosphazene derivatives, N 3 P 3 Cl 4 R 2 [R=NHPh, (HN(CH 2 ) 3 NH) 0.5 , (OCH 2 C(CH 3 ) 2 CH 2 O) 0.5 ], (1–3), with spermine (4), in aprotic solvents such as CH 2 Cl 2 results in a series of dispirobino spermine derivatives of cyclotriphosphazene (5a, 6a, 7), namely spermine bridged compounds. Whereas, in protic solvents such as CHCl 3 give, dispiroansa derivatives (8–10) namely tetracyclic cyclotriphosphazene. The new series of dispirobino and dispiroansa spermine derivatives of cyclotriphosphazene (5a, 6a, 7–10) have been characterised by elemental analysis, mass spectrometry, X-ray (for 5a, 8, 10) and 1 H, 31 P NMR spectroscopies.