RESEARCH ON CHEMICAL INTERMEDIATES, cilt.47, sa.10, ss.3933-3962, 2021 (SCI-Expanded)
The N3P3 ring of hexachlorocyclotriphosphazene, N3P3Cl6 (1) (HCCP; trimer), was used significantly as a scaffold for the syntheses of inorganic-organic-based hybrid cyclotriphosphazenes, as it is a highly robust skeleton among inorganic phosphorus-nitrogen ring systems. However, hybrid cyclotriphosphazenes with pendant arm(s) have been quite less explored. In the present study, the unsymmetrical bulky 4-methoxybenzyldiamines, CH3OPhCH2NH(CH2)(n)NHR (n=0, R=CH3 2; n=0, R=C(2)H(5 )3 and n=1, R = CH(3 )4), were obtained after the reduction of the corresponding Schiff bases formed as a result of condensation reactions of aliphatic diamines with 4-methoxybenzaldehyde. Reactions of the diamines (2-4) with HCCP (1) gave the new monospiro-(5-7), cis-dispiro (8-10) and trans-dispiro (11-13) cyclotriphosphazenes with 4-methoxybenzyl (p-anisyl) pendant arm(s). The fully substituted monospiro derivatives; 5a-7a, 5b-7b and 5c-7c, were prepared from the reactions of 5, 6 and 7 with pyrrolidine, tetra-1,4-dioxa-8-azaspiro[4.5]decane and piperidine, respectively. FTIR, ESI-MS and H-1, C-13, P-31 NMR spectral data of all cyclotriphosphazenes were presented. The cis-dispiro (8-10) and trans-dispiro (11-13) cyclotriphosphazenes have two-equal stereogenic P-centers, and they can form cis (meso; RS/SR) and trans (racemic; RR/SS) optical isomers. The molecular and crystal structures of 7 and 11 were revealed by X-ray crystallography. The space group of compound 11 was found to be P - 1, and the absolute configurations of the centers P1 and P2 were determined as S and S, respectively. In addition, the antibacterial and antifungal activities of fourteen cyclotriphosphazenes against G(-) and G( +) bacteria and fungi were determined. The interactions of cyclotriphosphazenes with plasmid DNA were investigated using agarose gel electrophoresis.