Metabolite identification via LC-SPE-NMR-MS of the in vitro biooxidation products of a lead mGlu5 allosteric antagonist and impact on the improvement of metabolic stability in the series.
Detailed information on the metabolic fate of lead compounds can be a powerful tool for an informed approach to the stabilization of metabolically labile compounds in the lead optimization phase. The combination of high performance liquid chromatography (HPLC) with nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MS) has been used to give comprehensive structural data on metabolites of novel drugs in development. Recently, increased automation and the embedding of on-line solid-phase extraction (SPE) into a integrated LC-SPE-NMR-MS system have improved enormously the detection limits of this approach. The new technology platform allows the analysis of complex mixtures from microsome incubations, combining low material requirements with relatively high throughput. Such characteristics make it possible to thoroughly characterize metabolites of selected compounds at earlier phases along the path to lead identification and clinical candidate selection, thus providing outstanding guidance in the process of eliminating undesired metabolism and detecting active or potentially toxic metabolites. Such an approach was applied at the lead identification stage of a backup program on metabotropic glutamate receptor 5 (mGlu5) allosteric inhibition. The major metabolites of a lead 5-aminothiazole-4-carboxylic acid amide 1 were synthesized and screened, revealing significant in vitro activity and possible involvement in the overall pharmacodynamic behavior of 1. The information collected on the metabolism of the highly active compound 1 was pivotal to the synthesis of related compounds with improved microsomal stability.
Ceccarelli
Simona M
SM
Pharmaceuticals Division, F. Hoffmann-La Roche AG, 4070 Basel, Switzerland. simona_m.ceccarelli@roche.com
Schlotterbeck
Götz
G
Boissin
Patrick
P
Binder
Martin
M
Buettelmann
Bernd
B
Hanlon
Steven
S
Jaeschke
Georg
G
Kolczewski
Sabine
S
Kupfer
Ernst
E
Peters
Jens-Uwe
JU
Porter
Richard H P
RH
Prinssen
Eric P
EP
Rueher
Marianne
M
Ruf
Iris
I
Spooren
Will
W
Stämpfli
Andreas
A
Vieira
Eric
E
D000494:Allosteric Regulation; D000631:Aminopyridines / Q000138:chemical synthesis / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006801:Humans; D020128:Inhibitory Concentration 50; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D013058:Mass Spectrometry / Q000379:methods; D008862:Microsomes, Liver / Q000737:chemistry / Q000378:metabolism*; D010084:Oxidation-Reduction; D004364:Pharmaceutical Preparations / Q000138:chemical synthesis / Q000378:metabolism*; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate / Q000037:antagonists & inhibitors*; D052616:Solid Phase Extraction / Q000379:methods; D013237:Stereoisomerism; D013844:Thiazoles / Q000138:chemical synthesis / Q000378:metabolism*
D000631:Aminopyridines; D004364:Pharmaceutical Preparations; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate; D013844:Thiazoles