The discovery of novel 5,6,5- and 5,5,6-tricyclic pyrrolidines as potent and selective DPP-4 inhibitors.
Cox, J.M., Chu, H.D., Kuethe, J.T., Gao, Y.D., Scapin, G., Eiermann, G., He, H., Li, X., Lyons, K.A., Metzger, J., Petrov, A., Wu, J.K., Xu, S., Sinha-Roy, R., Weber, A.E., Biftu, T.(2016) Bioorg Med Chem Lett 26: 2622-2626
- PubMed: 27106708 
- DOI: https://doi.org/10.1016/j.bmcl.2016.04.020
- Primary Citation of Related Structures:  
5ISM - PubMed Abstract: 
Novel potent and selective 5,6,5- and 5,5,6-tricyclic pyrrolidine dipeptidyl peptidase IV (DPP-4) inhibitors were identified. Structure-activity relationship (SAR) efforts focused on improving the intrinsic DPP-4 inhibition potency, increasing protease selectivity, and demonstrating clean ion channel and cytochrome P450 profiles while trying to achieve a pharmacokinetic profile suitable for once weekly dosing in humans.
Organizational Affiliation: 
Department of Chemistry, Merck Research Laboratories, 2015 Galloping Hill Road, Kenilworth, NJ 07033, USA. Electronic address: jason_cox@merck.com.