Synthesis of 5-[-2(3-Benzyloxy-2-methylamino-propionylamino-3-methyl-pentanoylamino] 6-oxo-heptyl}-carbamic Acid 9H-fluoren-9-ylmethyl Ester (‘VAV-NH-(PEG)₂₃-NH-VAV’, the hydrogel) from NH₂(PEG)₂₃NH₂ and NCA VAV) and a Study of the Polymerisation Kinetics

摘要

Amine terminated Polyethyl glycol (NH₂(PEG)₂₃NH₂) and 4,8-diisopropyl-6-methyl-1,3,9-oxadiazecane-2,5,7,10-tetrone (NCA VAV) were used to synthesize the hydrogel 5-[-2(3-Benzyloxy-2-methylamino-propionylamino-3-methyl-pentanoylamino] 6-oxo-heptyl}-carbamic acid 9H-fluoren-9-ylmethyl ester (‘VAV-NH-(PEG)₂₃-NH-VAV’). The hydrogel was characterized using proton and carbon NMR together with other spectroscopic techniques. The kinetics of the reaction were investigated in situ in an NMR tube in order to establish the mechanism of the polymerization of 4,8-diisopropyl-6-methyl-1,3,9-oxadiazecane-2,5,7,10-tetrone (NCA VAV with the di-functional diamide poly (ethylene) glycol, as an initiator. The reaction was found to proceed by 1^st order mechanism with respect to the NCA VAV concentration.