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The conversion of glyoxyloyl groups into glycyl groups and their formation from maleyl residues

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... 652 Lastly, glyoxyloyles can easily be transformed into corresponding amines via transamination reaction in the presence of copper(II) or nickel(II) salts. 604,610,653 The reaction mechanism as well as need for both essential components of the system: the acceptor of the glyoxyloyl (usually aspartic acid or glycine) and the cation of a heavy metal are explained in Fig. 75. Despite being of moderate interest for bioconjugation by itself, this approach has initiated the development of a more general methodology for selective N-terminus modification -transaminative conjugation (Section 2.1.3). ...
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