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A new method for the preparation of poly(oxyethylene phosphoramidate)s and glycopolymers is developed via modification of poly(oxyethylene H-phosphonate) which is a biodegradable, biocompatible and low toxic polymer. The phosphonate groups of the precursor are converted into tri-coordinated phosphorus species yielding poly(oxyethylene trimethylsilyl phosphite). The latter is then reacted with different azides, including sugar azides, via Staudinger reaction to furnish the desired poly(oxyethylene phosphoramidate)s and such containing sugar moieties in the side chains attached to the P-centers. 2002P NMR spectroscopy is applied as a powerful tool for determination of the conversion and structure of the reaction products. Studies on Concanavalin A binding to the obtained glycopolymers are performed using dynamic light scattering and analytical ultracentrifugation techniques. The viability of Human Embryonic Kidney 293 cell line is slightly affected when exposed to polyphosphoramidate glucoconjugate over a broad range of concentrations. The results obtained are encouraging for further investigations on the clustering and bio-recognition properties of the synthesized glycopolymers. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017

Phosphorus-containing polymers present a diverse class of materials that comprise natural and synthetic polymers, organic and inorganic macromolecules. The main representatives of the synthetic group include the polyphosphoesters and polyphosphazenes. These polymers are attractive for biomedical applications due to their biocompatibility and biodegradability—essential properties of the biomaterials. The reactivity of the phosphorus atom allows development of a versatile polymer platform with convenient manipulation of functionalities and properties of the material. The aim of this chapter is to outline the specific and advantageous characteristics of the phosphorus-containing polymers and the strategies used to adjust these properties to a specific bio-application with the emphasis on nanotherapeutic systems. Results from comparative studies on polyphosphoesters and some polymers approved for biomedical applications, i.e., PLA and PEG, are also given to convince the reader of the great potential of the phosphorus-containing polymers as alternative materials in the biomedical field.

A novel phosphorus-containing biocompatible and biodegradable star-shaped polymer was designed as a precursor polymer for obtaining sugar or drug conjugates. The star polymer bearing three arms was synthesized applying the “coupling on” approach. Linear oligo(oxyethylene H-phosphonate) with a terminal hydroxyl group was prepared and used as functional arms able to react with tris(2,3-epoxypropyl) isocyanurate as core in the presence of boron trifluoride etherate as catalyst. The H-phosphonate moieties in the arm chains were transformed into trimethylsilyl phosphite groups and further via Staudinger reaction they were converted into phosphoramidates bearing specific residues. When the Staudinger reaction was carried out with a glucose-containing azide, i.e. 2-p-azidobenzamide-2-deoxy-1,3,4,6-tetra-O-trimethylsilyl-alpha-D-glucopyranose, the product was a star-shaped glycopolymer. The conjugation of AZT yielded a star-shaped polymer-drug conjugate. Multinuclear NMR spectroscopy was applied as a powerful tool for determination of the conversion and structure of the reaction products. Analytical ultracentrifugation, dynamic and electrophoretic light scattering techniques were used for characterization of the star polymers and conjugates, as well as in binding studies with Concanavalin A. Drug release measurements and cytotoxicity tests were also performed. The obtained results evidenced feasible synthetic procedures for preparation of biocompatible phosphorus containing star-shaped glycopolymer and drug conjugate.

Well-defined poly(alkylene trimethylsilylphosphite)s (P + 3) were obtained for the first time via silylation of poly(oxyethylene H-phosphonate)s (P + 5) with N,O-bis(trimethylsilyl)acetamide or trimethylsilyl chloride. The reaction with both silylating agents proceeds at room temperature in quantitative conversion. It has been followed by 1 H and 31 P NMR spectroscopy. Poly(alkylene trimethylsilylphosphite)s represent important precursors for the preparation of polymeric aminophosphonic acids, α-hydroxyphosphonates, as well as in a Staudinger-polyphosphite reaction with azides yielding polyphosphoramides.