Diaryl urea analogues of SB-334867 as orexin-1 receptor antagonists
Perrey, D. A., Gilmour, B., Runyon, S., Thomas, B., & Zhang, Y. (2011). Diaryl urea analogues of SB-334867 as orexin-1 receptor antagonists. Bioorganic and Medicinal Chemistry Letters, 21(10), 2980-2985.
As a part of our program to develop OX1-CB1 bivalent ligands, we required a better understanding of the basic structure-activity relationships (SARs) of orexin antagonists. A series of SB-334867 analogues were synthesized and evaluated in calcium mobilization assays. SAR results suggest that the 2-methylbenzoxazole moiety may be replaced with a disubstituted 4-aminophenyl group without loss of activity and an electron-deficient system is generally preferred at the 1,5-naphthyridine moiety for OX1 antagonist activity. In particular, substitution of larger potential linkers such as n-hexyl provided compound 33 with equivalent activity at the OX1 receptor compared to the lead compound SB-334867. These compounds should be of value in the development of ligands targeting the orexin-1 receptor and its potential heterodimers. (C) 2011 Elsevier Ltd. All rights reserved