(Chemical Equation Presented) External bicyclic β-turn dipeptide mimetics provide an excellent design approach that can offer a rich chiral ensemble of structures with different backbone conformations. We report herein a novel design of a convergent combinatorial synthetic methodology, which is illustrated by the solid-phase synthesis of a series of [3.3.0]-bicyclo [2,3]-Leu-enkephalin analogues. The reactions were optimized and the epimeric configurations were determined by 2D NMR spectroscopy. Biological assays show that these analogues have more potent δ binding affinity and bioactivity for δ vs μ opioid receptor, which may be related to the different conformations preferred by these analogues in our modeling studies.
ASJC Scopus subject areas
- Physical and Theoretical Chemistry
- Organic Chemistry