NMR and DSC studies on the reactions of pentanedioxy spiro-ansa cyclochlorotriphosphazene and pentanedioxy triple-bridged cylochlorotriphosphazene with monofunctional nucleophiles

In this study, the reactions of 2-(2-hydroxyethyl) thiophene (2) and benzyl alcohol (3) with pentanedioxycyclochlorotriphosphazene (1) and pentanedioxy triple-bridged cylochlorotriphosphazene (6) were studied. The novel cyclotriphosphazene compounds: two di-substituted spiro-ansa, N3P3[O(CH2)5O]- (C6H7OS)]2 (4) and N3P3[O(CH2)5O-(C6H5CH2O)]2 (5); and two fully substituted triple-bridged, N3P3[O(CH2)5O]3-(C6H7OS)6N3P3 (7) and N3P3[O(CH2)5O]3-(C6H5CH2O)6N3P3 (8) derivatives were formed in THF solvent by using NaH base at ambient conditions. Because of their variety of applications, there is a great deal of interest in the preparation of aromatic macrocyclic derivatives of cyclophosphazenes. The main purpose of these studies is to develop bioactive cyclophosphazene derivatives in the search for new effective drug candidates for the treatment of various diseases, in particular, anticancer and antimicrobials. The synthesized compounds (4, 5, 7, 8) were defined using analytical techniques namely Element analysis, TLC/MS system, and NMR spectroscopy. Thermal stabilities, crystal purity, and recrystallization properties and corresponding enthalpies of synthesized derivatives were analyzed in the course of heating and cooling cycles of DSC.

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