A series of dipeptide aldehydes containing different N-terminal heterocycles was prepared and assayed in vitro against α-chymotrypsin to ascertain the importance of the heterocycle in maintaining a β-strand geometry while also providing a hydrogen bond donor equivalent to the backbone amide nitrogen of the surrogate amino acid. The dipeptide containing a pyrrole constraint (10) was the most potent
                                    制备了一系列含有不同N末端杂环的二肽醛,并在体外针对α-胰凝乳
蛋白酶进行了分析,以确定该杂环在维持β链几何结构的重要性的同时,还提供了一个与H2的主链酰胺氮等效的氢键供体。替代
氨基酸。含有
吡咯约束的二肽(10)是最有效的
抑制剂,其活性比缺乏氮氢键供体的二肽(即
噻吩11,
呋喃12和
吡啶13)提高了30倍以上。与α-胰凝乳
蛋白酶结合的10的分子对接研究表明,
吡咯氮供体与位于S3口袋中的Gly216的主链羰基之间存在氢键,这对整体结合至关重要。