33. Arylboronate Ester Protected Amino Acids as Orthogonal Building Blocks for Fmoc Solid‐Phase Peptide Synthesis

Liu, C.; Zou, Y.; Song, H.; Jiang, Y.-Y.;* Hu, H.-G.*  Eur. J. Org. Chem. 2017, 5916–5920. Download Link

Abstract: Three new arylboronate ester protected amino acids and their on-resin deprotection methods have been developed. These useful building blocks were found to exhibit favorable chemical properties that are fully compatible with Fmoc strategy solid-phase peptide synthesis. Furthermore, the formation of over-oxidation side-product methionine was minimized by using N-methyl-N-phenylaniline N-oxide as the oxidizing reagent. Effective application of the three new amino acids for the synthesis of different types of peptidomimetics has been demonstrated by high-quality preparation of lipidated peptide MP-196 C-C8, on-resin head-to-tail cyclization of desotamide B, and lactam bridging of hPTHrP-(11–19) through a facile and metal-free procedure by standard Fmoc solid-phase peptide synthesis.