Synthesis and spectroscopic properties of (N/O) mono- and dispirocyclotriphosphazene derivatives with benzyl pendant arms: study of biological activity

Abstract

The Cl replacement reactions of hexachlorocyclotriphosphazene (trimer; N 3 P 3 Cl 6) with sodium (N-benzyl)aminopropanoxides (1 and 2) produced monospiro-(3 and 4), cis-, and trans-dispirocyclotriphosphazenes (13-16). The monospiro tetrakis-aminocyclotriphosphazenes (5-12) were obtained by the Cl substitutions of 3 and 4 with different secondary amines. The cis-(13 and 14) and trans-dispirophosphazenes (15 and 16) possessed 2 chiral P centers, and they were able to present meso and racemic forms, respectively. Moreover, the structures of compounds 5 and 14 were designated using X-ray data. The absolute configuration of compound 14 was found as SR in the solid state. Analytical and spectroscopic data of the phosphazenes were consistent with their suggested structures. Antimicrobial activities of the benzyl-pendant-armed cyclotriphosphazenes were scrutinized against G(+) and G(−) bacteria and yeast strains. The bacterium most affected by the synthesized compounds was Pseudomonas aeruginosa. Minimum inhibitory concentrations and minimal bacterial concentrations were in the range of 125-500 µ M. Interactions between the phosphazenes (3-12 and 15) and plasmid DNA were studied with agarose gel electrophoresis. The phosphazene-DNA interaction studies of the cyclotriphosphazenes revealed that phosphazenes 3, 4, and 15 had a substantial effect on supercoiled DNA by cleavage of the double helix.

Phosphorus–nitrogen compounds: part 68. Synthesis, characterization, stereogenism, photophysical and bioactivity studies of novel unsymmetrical dispiro(N/N)cyclotriphosphazenes with carbazolyl and 4-chlorobenzyl pendant arms

“…25,26 In both phosphazenes, there are regular changes in endocyclic PN bond lengths in terms of the distances to P1: P1–N1 ≈ P3–N2 > P1–N3 ≈ P3–N3 > P2–N1 ≈ P2–N2, as observed in previous studies. 26,58…”

Phosphorus–nitrogen compounds: part 71. Novel unsymmetrically-substituted dispiro-cyclotriphosphazenes: synthesis, characterization, antituberculosis activity, and phototunable charge storage studies

“…Different geometrical isomers (geminal and nongeminal cis / trans ) and different architectures, such as monospiro-, dispiro-, trispiro-, bino-, ansa-, spiro-bino-spiro ( sbs ), and spiro-ansa-spiro ( sas ), can be obtained using monodentate, bidentate, and polydentate ligands. 15–21 Among these, the number of monospirocyclotriphosphazenes is much greater than others. In addition to the studies on symmetrical dispirophosphazenes in the literature, a few studies on unsymmetrical-substituted dispirophosphazenes have also been encountered.…”