TY - JOUR
T1 - Synthesis and biological evaluation of 4-(aminomethyl)-1-hydroxypyrazole analogues of muscimol as ¿-aminobutyric acidA receptor agonists
AU - Petersen, Jette Gellert
AU - Bergmann, Rikke
AU - Møller, Henriette A.
AU - Jørgensen, Charlotte Grube
AU - Nielsen, Birgitte
AU - Kehler, Jan
AU - Frydenvang, Karla
AU - Kristensen, Jesper
AU - Balle, Thomas
AU - Jensen, Anders A.
AU - Kristiansen, Uffe
AU - Frølund, Bente
PY - 2013/2/14
Y1 - 2013/2/14
N2 - A series of bioisosteric 4-(aminomethyl)-1-hydroxypyrazole (4-AHP) analogues of muscimol, a GABAA receptor agonist, has been synthesized and pharmacologically characterized at native and selected recombinant GABAA receptors. The unsubstituted 4-AHP analogue (2a) (EC 50 19 μM, Rmax 69%) was a moderately potent agonist at human α1β2γ2 GABAA receptors, and in SAR studies substitutions in the 3- and/or 5-position were found to be detrimental to binding affinities. Ligand-receptor docking in an α1β2γ2 GABAA receptor homology model along with the obtained SAR indicate that 2a and muscimol share a common binding mode, which deviates from the binding mode of the structurally related antagonist series based on 4-(piperidin-4-yl)-1- hydroxypyrazole (4-PHP, 1). Selectivity for α1β 2γ2 over ρ1 GABAA receptors was observed for the 5-chloro, 5-bromo, and 5-methyl substituted analogues of 2a illustrating that even small differences in structure can give rise to subtype selectivity.
AB - A series of bioisosteric 4-(aminomethyl)-1-hydroxypyrazole (4-AHP) analogues of muscimol, a GABAA receptor agonist, has been synthesized and pharmacologically characterized at native and selected recombinant GABAA receptors. The unsubstituted 4-AHP analogue (2a) (EC 50 19 μM, Rmax 69%) was a moderately potent agonist at human α1β2γ2 GABAA receptors, and in SAR studies substitutions in the 3- and/or 5-position were found to be detrimental to binding affinities. Ligand-receptor docking in an α1β2γ2 GABAA receptor homology model along with the obtained SAR indicate that 2a and muscimol share a common binding mode, which deviates from the binding mode of the structurally related antagonist series based on 4-(piperidin-4-yl)-1- hydroxypyrazole (4-PHP, 1). Selectivity for α1β 2γ2 over ρ1 GABAA receptors was observed for the 5-chloro, 5-bromo, and 5-methyl substituted analogues of 2a illustrating that even small differences in structure can give rise to subtype selectivity.
U2 - 10.1021/jm301473k
DO - 10.1021/jm301473k
M3 - Journal article
C2 - 23294161
SN - 0022-2623
VL - 56
SP - 993
EP - 1006
JO - Journal of Medicinal Chemistry
JF - Journal of Medicinal Chemistry
IS - 3
ER -