Purine (N)-Methanocarba Nucleoside Derivatives Lacking an Exocyclic Amine as Selective A3 Adenosine Receptor Agonists. J Med Chem 2016 Apr 14;59(7):3249-63
Date
02/19/2016Pubmed ID
26890707Pubmed Central ID
PMC4970510DOI
10.1021/acs.jmedchem.5b01998Scopus ID
2-s2.0-84966397565 (requires institutional sign-in at Scopus site) 14 CitationsAbstract
Purine (N)-methanocarba-5'-N-alkyluronamidoriboside A3 adenosine receptor (A3AR) agonists lacking an exocyclic amine resulted from an unexpected reaction during a Sonogashira coupling and subsequent aminolysis. Because the initial C6-Me and C6-styryl derivatives had unexpectedly high A3AR affinity, other rigid nucleoside analogues lacking an exocyclic amine were prepared. Of these, the C6-Me-(2-phenylethynyl) and C2-(5-chlorothienylethynyl) analogues were particularly potent, with human A3AR Ki values of 6 and 42 nM, respectively. Additionally, the C2-(5-chlorothienyl)-6-H analogue was potent and selective at A3AR (MRS7220, Ki 60 nM) and also completely reversed mouse sciatic nerve mechanoallodynia (in vivo, 3 μmol/kg, po). The lack of a C6 H-bond donor while maintaining A3AR affinity and efficacy could be rationalized by homology modeling and docking of these hypermodified nucleosides. The modeling suggests that a suitable combination of stabilizing features can partially compensate for the lack of an exocyclic amine, an otherwise important contributor to recognition in the A3AR binding site.
Author List
Tosh DK, Ciancetta A, Warnick E, O'Connor R, Chen Z, Gizewski E, Crane S, Gao ZG, Auchampach JA, Salvemini D, Jacobson KAAuthor
John A. Auchampach PhD Professor in the Pharmacology and Toxicology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
Adenosine A3 Receptor AgonistsAdministration, Oral
Animals
CHO Cells
Carbohydrates
Cricetinae
Cricetulus
HEK293 Cells
Humans
Mice
Models, Molecular
Nucleosides
Pain
Purines
Receptor, Adenosine A3
Structure-Activity Relationship