Ribose-Modified Nucleosides as Ligands for Adenosine Receptors: Synthesis, Conformational Analysis, and Biological Evaluation of 1‘-C-Methyl Adenosine Analogues
摘要:
1'-C-Methyl analogues of adenosine and selective adenosine A, receptor agonists, such as N-[(1R)-1-methyl-2-phenylethyl]adenosine ((R)-PIA) and N-6-cyclopentyladenosine, were synthesized to further investigate the subdomain that binds the ribose moiety. Binding affinities of these new compounds at A(1) and A(2A) receptors in rat brain membranes and at A(3) in rat testis membranes were determined and compared. It was found that the 1'-C-methyl modification in adenosine resulted in a decrease of affinity, particularly at A(1) and A(2A) receptors. When this modification was combined with N-6 substitutions with groups that induce high potency and selectivity at A(3) receptors, the high affinity was in part restored and the selectivity was increased. The most potent compound proved to be the V-C-methyl analogue of (R)-PIA with a K-i of 23 nM for the displacement of [H-3]CHA binding from rat brain A(1) receptors and a >435-fold selectivity over A(2A) receptors. In functional assays, these compounds inhibited forskolin-stimulated adenylate cyclase with IC50 values ranging from 0.065 to 3.4 muM, acting as full agonists. Conformational analysis based on vicinal proton-proton J-coupling constants and molecular mechanics calculations using the MM2 force field proved that the methyl group on C1' in adenosine has a pronounced impact on the furanose conformation by driving its conformational equilibrium toward the north, gamma+, syn form.
Ribose-Modified Nucleosides as Ligands for Adenosine Receptors: Synthesis, Conformational Analysis, and Biological Evaluation of 1‘-C-Methyl Adenosine Analogues
摘要:
1'-C-Methyl analogues of adenosine and selective adenosine A, receptor agonists, such as N-[(1R)-1-methyl-2-phenylethyl]adenosine ((R)-PIA) and N-6-cyclopentyladenosine, were synthesized to further investigate the subdomain that binds the ribose moiety. Binding affinities of these new compounds at A(1) and A(2A) receptors in rat brain membranes and at A(3) in rat testis membranes were determined and compared. It was found that the 1'-C-methyl modification in adenosine resulted in a decrease of affinity, particularly at A(1) and A(2A) receptors. When this modification was combined with N-6 substitutions with groups that induce high potency and selectivity at A(3) receptors, the high affinity was in part restored and the selectivity was increased. The most potent compound proved to be the V-C-methyl analogue of (R)-PIA with a K-i of 23 nM for the displacement of [H-3]CHA binding from rat brain A(1) receptors and a >435-fold selectivity over A(2A) receptors. In functional assays, these compounds inhibited forskolin-stimulated adenylate cyclase with IC50 values ranging from 0.065 to 3.4 muM, acting as full agonists. Conformational analysis based on vicinal proton-proton J-coupling constants and molecular mechanics calculations using the MM2 force field proved that the methyl group on C1' in adenosine has a pronounced impact on the furanose conformation by driving its conformational equilibrium toward the north, gamma+, syn form.
Sugar modified nucleosides as viral replication inhibitors
申请人:Hong Zhi
公开号:US20070032448A1
公开(公告)日:2007-02-08
Various 2′-modified nucleoside analogs and corresponding prodrugs are provided, and particularly contemplated methods of use include use as antiviral agents, and especially as antiviral agents against HCV.
Ribose-Modified Nucleosides as Ligands for Adenosine Receptors: Synthesis, Conformational Analysis, and Biological Evaluation of 1‘-<i>C</i>-Methyl Adenosine Analogues
1'-C-Methyl analogues of adenosine and selective adenosine A, receptor agonists, such as N-[(1R)-1-methyl-2-phenylethyl]adenosine ((R)-PIA) and N-6-cyclopentyladenosine, were synthesized to further investigate the subdomain that binds the ribose moiety. Binding affinities of these new compounds at A(1) and A(2A) receptors in rat brain membranes and at A(3) in rat testis membranes were determined and compared. It was found that the 1'-C-methyl modification in adenosine resulted in a decrease of affinity, particularly at A(1) and A(2A) receptors. When this modification was combined with N-6 substitutions with groups that induce high potency and selectivity at A(3) receptors, the high affinity was in part restored and the selectivity was increased. The most potent compound proved to be the V-C-methyl analogue of (R)-PIA with a K-i of 23 nM for the displacement of [H-3]CHA binding from rat brain A(1) receptors and a >435-fold selectivity over A(2A) receptors. In functional assays, these compounds inhibited forskolin-stimulated adenylate cyclase with IC50 values ranging from 0.065 to 3.4 muM, acting as full agonists. Conformational analysis based on vicinal proton-proton J-coupling constants and molecular mechanics calculations using the MM2 force field proved that the methyl group on C1' in adenosine has a pronounced impact on the furanose conformation by driving its conformational equilibrium toward the north, gamma+, syn form.