Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA.
J Org Chem. 2013 Apr 19;78(8):3541-52. doi: 10.1021/jo302251e. Epub 2013 Apr 10.
Novel N-(N-Pg-azadipeptidoyl)benzotriazoles 20a-e couple efficiently with α-amino acids 21a-e, dipeptides 22a-c, aminoxyacetic acid 23a, depsidipeptide 23b, and α-hydroxy-β-phenylpropionic acid 27 yielding, respectively, azatripeptides 24a-g, azatetrapeptides 25a,b, a hybrid azatripeptide with an oxyamide bond 26a, a hybrid azatetrapeptide with an ester bond 26b, and a hybrid azatripeptide with an ester bond 28. A new protocol for the synthesis of N-Pg-azatripeptides 33a,b and 35a,b, each containing a natural amino acid at the N-terminus, avoids the low coupling rates of the aza-amino acid residue and enables the solution-phase synthesis of an azaphenylalanine analogue of Leu-enkephalin 40.
新型 N-（N-Pg-脒基肽酰）苯并三唑 20a-e 可有效地与α-氨基酸 21a-e、二肽 22a-c、氨氧基乙酸 23a、去甲二肽 23b 和 α-羟基-β-苯丙酸 27 偶联，分别生成氮三肽 24a-g、氮四肽 25a,b、含有氧酰胺键的混合氮三肽 26a、含有酯键的混合氮四肽 26b 和含有酯键的混合氮三肽 28。一种新的合成 N-Pg-氮三肽 33a,b 和 35a,b 的方案，每个都在 N 端含有天然氨基酸，避免了 aza-氨基酸残基的低偶联率，并实现了亮啡肽 40 的氮杂苯丙氨酸类似物的溶液相合成。
