Potent and Selective Ligands for Adenosine Binding Sites
摘要:
A number of selective ligands for the different binding sites of adenosine have been synthesized and tested in several pharmacological models. The aim of these synthetic efforts is both to improve the knowledge of structure-activity relationships in the adenosine-related biological systems and to develop drugs from some of these molecules.
N-Cycloalkyl Derivatives of Adenosine and 1-Deazaadenosine as Agonists and Partial Agonists of the A1 Adenosine Receptor
摘要:
A number of cycloalkyl substituents (from C-3 to C-8) have been int-reduced on the 6-amino group of adenosine, 1-deazaadenosine, and 2'-deoxyadenosine, bearing or not a chlorine atom at the 2-position, to evaluate the influence on the A(1) and A(2A) affinity of steric hindrance and lipophilicity. Furthermore, the guanosine 5'-triphosphate (GTP) shift and the maximal induction of guanosine 5'-(gamma-thio)triphosphate ([S-35]GTP gamma S) binding to G proteins in rat brain membranes were used to determine the intrinsic activity of these nucleosides at the A(1) adenosine receptor. All compounds of the ribose-bearing series proved to be full agonists, the 1-deaza derivatives showing affinities for the Al receptor about 10-fold lower than the corresponding adenosines. On the other hand, all the 2'-deoxyribose derivatives bind to the A(1) receptor with affinities in the high nanomolar range, with the 2-chloro substituted compounds showing slightly higher affinities than the 2-unsubstituted counterparts. In terms of the potencies, the most potent compounds proved to be those bearing four- and five-membered rings. Both GTP shifts and [S-35]-GTP gamma S experiments showed that most of the 2'-deoxyadenosine derivatives are partial agonists, The 2'-deoxyadenosine derivatives which were identified as partial agonists consistently detected fewer Az receptors in the high-affinity state than full agonists. However, it is worthwhile noting that there was not a simple Linear relationship between receptor occupancy and activation. These results indicate that a critical density of A(1) adenosine receptors in the high-affinity state is required for G protein activation.
<i>N</i>-Cycloalkyl Derivatives of Adenosine and 1-Deazaadenosine as Agonists and Partial Agonists of the A<sub>1</sub> Adenosine Receptor
作者:Sauro Vittori、Anna Lorenzen、Christina Stannek、Stefano Costanzi、Rosaria Volpini、Adriaan P. IJzerman、Jakobien K. Von Frijtag Drabbe Kunzel、Gloria Cristalli
DOI:10.1021/jm9911231
日期:2000.1.1
A number of cycloalkyl substituents (from C-3 to C-8) have been int-reduced on the 6-amino group of adenosine, 1-deazaadenosine, and 2'-deoxyadenosine, bearing or not a chlorine atom at the 2-position, to evaluate the influence on the A(1) and A(2A) affinity of steric hindrance and lipophilicity. Furthermore, the guanosine 5'-triphosphate (GTP) shift and the maximal induction of guanosine 5'-(gamma-thio)triphosphate ([S-35]GTP gamma S) binding to G proteins in rat brain membranes were used to determine the intrinsic activity of these nucleosides at the A(1) adenosine receptor. All compounds of the ribose-bearing series proved to be full agonists, the 1-deaza derivatives showing affinities for the Al receptor about 10-fold lower than the corresponding adenosines. On the other hand, all the 2'-deoxyribose derivatives bind to the A(1) receptor with affinities in the high nanomolar range, with the 2-chloro substituted compounds showing slightly higher affinities than the 2-unsubstituted counterparts. In terms of the potencies, the most potent compounds proved to be those bearing four- and five-membered rings. Both GTP shifts and [S-35]-GTP gamma S experiments showed that most of the 2'-deoxyadenosine derivatives are partial agonists, The 2'-deoxyadenosine derivatives which were identified as partial agonists consistently detected fewer Az receptors in the high-affinity state than full agonists. However, it is worthwhile noting that there was not a simple Linear relationship between receptor occupancy and activation. These results indicate that a critical density of A(1) adenosine receptors in the high-affinity state is required for G protein activation.
Potent and Selective Ligands for Adenosine Binding Sites
作者:G. Cristalli、E. Camaioni、E. Di Francesco、A. Eleuteri、S. Vittori、R. Volpini
DOI:10.1080/07328319708006189
日期:1997.7
A number of selective ligands for the different binding sites of adenosine have been synthesized and tested in several pharmacological models. The aim of these synthetic efforts is both to improve the knowledge of structure-activity relationships in the adenosine-related biological systems and to develop drugs from some of these molecules.