Discovery of potent and orally bioavailable macrocyclic peptide-peptoid hybrid CXCR7 modulators.

by Markus Boehm, Kevin Beaumont, Rhys M Jones, Amit S. Kalgutkar, Liying Zhang, Karen Atkinson, Guoyun Bai, Janice A. Brown, Heather Eng, Gilles H. Goetz, Brian R Holder, Bhagyashree Khunte, Sarah Lazzaro, Chris Limberakis, Sangwoo Ryu, Michael J Shapiro, Laurie Tylaska, Jiangli Yan, Rushia Turner, Siegfried S. F. Leung, Mahesh Ramaseshan, David A. Price, Spiros Liras, Matthew P Jacobson, David J. Earp, R. Scott Lokey, Alan M Mathiowetz, and Elnaz Menhaji-Klotz

ABSTRACT: The chemokine receptor CXCR7 is an attractive target for a variety of diseases. While several small molecule modulators of CXCR7 have been reported, peptidic macrocycles may provide advantages in terms of potency, selectivity, and reduced off-target activity. We produced a series of peptidic macrocycles that incorporate an N-linked peptoid functionality where the peptoid group enabled us to explore side chain diversity well beyond that of natural amino acids. At the same time, computational calculations and experimental assays were used to track and reduce polarity while closely monitoring physicochemical properties. This strategy led to the discovery of macrocyclic peptide-peptoid hybrids with high CXCR7 binding affinities (Ki < 100 nM) and measurable passive permeability (Papp > 5 x 10-6 cm/sec). Moreover, bioactive peptide 25 (Ki = 9 nM) achieved oral bioavailability of 18% in rats, which was commensurate with the observed plasma clearance values upon intravenous administration.

October 18, 2017
Journal of Medicinal Chemistry
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