PyAOP is a coupling reagent used to prepare amides from carboxylic acids and amines in peptide synthesis[1]. PyAOP is a derivative of the HOAt family of amide bond forming reagents, mediating the formation of amide bonds without the risk of guanidine formation, and is the preferred reagent for peptide cyclization[2, 3]. PyAOP can synthesize N, N′-substituted acylguanidines by solid phase peptide synthesis and promote the formation of peptide bonds during the synthesis of cyclic peptide hybrids[4, 5]. PyAOP can replace HATU to complete the coupling of Arg and Phe[6].
References:
[1] Hu L, Zhao J. Ynamide: a new coupling reagent for amide and peptide synthesis[J]. Synlett, 2017, 28(14): 1663-1670.
[2] Albericio F, El-Faham A. Choosing the right coupling reagent for peptides: a twenty-five-year journey[J]. Organic Process Research & Development, 2018, 22(7): 760-772.
[3] Sarojini V, Cameron A J, Varnava K G, et al. Cyclic tetrapeptides from nature and design: A review of synthetic methodologies, structure, and function[J]. Chemical reviews, 2019, 119(17): 10318-10359.
[4] Dodd D S, Zhao Y. Solid-phase synthesis of N, N′-substituted acylguanidines[J]. Tetrahedron Letters, 2001, 42(7): 1259-1262.
[5] Planas M, Bardajı́ E, Barany G. Synthesis of cyclic peptide hybrids with amino acid and nucleobase side-chains[J]. Tetrahedron Letters, 2000, 41(21): 4097-4100.
[6] Evans E D, Pentelute B L. Discovery of a 29-amino-acid reactive abiotic peptide for selective cysteine arylation[J]. ACS chemical biology, 2017, 13(3): 527-532.