Asymmetric Synthesis of 3,4,6-Trisubstituted 2,5-Diketopiperazines by Using Dynamic Kinetic Resolution of α-Bromo Tertiary Acetamides
作者:Jinho Baek、Seock Yong Kang、Chan Im、Yong Sun Park
DOI:10.1002/ejoc.201301936
日期:2014.5
A new and efficient method for the asymmetric synthesis of 3,4,6-trisubstituted 2,5-diketopiperazines has been developed. The dynamickineticresolution of L-amino-acid-derived α-bromo tertiary amides in the nucleophilicsubstitution reaction with p-anisidine and a subsequent deprotection-cyclization process provides rapid access to diverse cis-2,5-diketopiperazines 5a–5o and proline-containing trans-2
Two synthetic routes for the synthesis of amino-triazolodiazepine (Ata) scaffolds are presented. The scope of both of these proceeding through key intra- and intermolecular Huisgen cycloaddition reactions is discussed. The replacement of the His-Pro dipeptide segment in angiotensin IV by the dipeptide mimetic Ata-Gly and subsequent biological evaluation in two inhibitory enzyme assays validated the use of the Ata moiety as a His mimic given the equipotency of both peptidic analogs.