The cytotoxic, cyclic heptadepsipeptide, natural product callipeltin B was synthesized on a solid-phase support in 15% overall yield. Comparison of the 1H NMR spectra of three synthetic isomers with those of callipeltin B confirmed the configurational reassignment of its threonine residues as d-allothreonine and the assignment of the configuration of its beta-methoxytyrosine residue as (2R,3R).
                                    细胞毒性、环状七肽、
天然产物 callipeltin B 在固相载体上合成,总产率为 15%。三种合成异构体的 1H NMR 谱与 callipeltin B 的 1H NMR 谱的比较证实其苏
氨酸残基的构型重新分配为 d-别苏
氨酸,并将其 β-甲氧基
酪氨酸残基的构型分配为 (2R,3R)。