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Updated: Aug 8, 2026

Preparation and Delivery of Protein Microcrystals in Lipidic Cubic Phase for Serial Femtosecond Crystallography
Published on: September 20, 2016
Potent and selective MC-4 receptor agonists based on a novel disulfide scaffold
Liang Z Yan1, David Flora, Patrick Edwards
1Lilly Research Laboratories, A Division of Eli Lilly & Co., Lilly Corporate Center, Indianapolis, IN 46285, USA. lyan@lilly.com
Abstract:
Extensive structure-activity relationship studies utilizing a beta-MSH-derived cyclic nonapeptide, Ac-Tyr-Arg-[Cys-Glu-His-D-Phe-Arg-Trp-Cys]-NH(2) (3), led to identification of a series of novel MC-4R selective disulfide-constrained hexapeptide analogs including Ac-[hCys-His-D-Phe-Arg-Trp-Cys]-NH(2) (12). The structural modifications associated with profound influence on MC-4R potency and selectivity were ring size, ring conformation, and the aromatic substitution of the D-Phe7. These cyclic peptide analogs provide novel and enhanced reagents for use in the elucidation of melanocortin-4 receptor-related physiology, and may additionally find application in the treatment of obesity and related metabolic disorders.
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