Product numbers 10011, Phthalimidooxy-dPEG®4-NHS ester, and 11135, Phthalimidooxy-dPEG®12-NHS ester, are amine-reactive protected oxyamine reagents containing a discrete PEG (dPEG®) spacer of either four (PN10011) or twelve (PN11135) ethylene oxide units. The phthalimidooxy protecting group can be removed by hydrazine.
