Conjugates of insulin.

A process for making a conjugate insulin-oligomer in a reaction in a single reactor comprising the steps of a) transpeptidation of insulin precursor to produce an ester of insulin, b) admixing said ester insulin in borate buffer with oligomer solubilised in acetonitrile, to achieve the release of said insulin ester and conjugation disk ester to said oligomer in insulin single reactor, c) obtaining an insulin-oligomer conjugate simultaneously.