Novel substituted 4-phenyl-[1,3]dioxanes: potent and selective orexin receptor 2 (OX(2)R) antagonists.
Bioorganic & medicinal chemistry letters 2004 Aug 16; 14(16):4225-9
McAtee L LC, Sutton S SW, Rudolph D DA, Li X X, Aluisio L LE, Phuong V VK, Dvorak C CA, Lovenberg T TW, Carruthers N NI, Jones T TK
Johnson and Johnson Pharmaceutical Research and Development, LLC, 3210 Merryfield Row, San Diego, CA 92121, USA.
Orexins, also termed hypocretins, consist of two neuropeptide agonists (orexin A and B) interacting with two known G-protein coupled receptors (OX(1)R and OX(2)R). In addition to other biological functions, the orexin-2 receptor is thought to be an important modulator of sleep and wakefulness. Herein we describe a series of novel, selective OX(2)R antagonists consisting of substituted 4-phenyl-[1,3]dioxanes. One such antagonist is compound 9, 1-(2,4-dibromo-phenyl)-3-((4S,5S)-2,2-dimethyl-4-phenyl-[1,3]dioxan-5-yl)-urea, which is bound by the OX(2)R with a pK(i) of 8.3, has a pK(b) of 7.9, and is 600-fold selective for the OX(2)R over the OX(1)R.