Measurement of atropisomer racemization kinetics using segmented flow technology.

When stable atropisomers are encountered by drug discovery teams, they can have important implications due to potential differences in their biological activity, pharmacokinetics, and toxicity. Knowledge of an atropisomer's activation parameters for interconversion is required to facilitate informed decisions on how to proceed. Herein, we communicate the development of a new method for the rapid measurement of atropisomer racemization kinetics utilizing segmented flow technology. This method leverages the speed, accuracy, low sample requirement, safety, and semiautomated nature of flow instrumentation to facilitate the acquisition of kinetics data required for experimentally probing atropisomer activation parameters. Measured kinetics data obtained for the atropo isomerization of AMPA antagonist CP-465021 using segmented flow and traditional thermal methods were compared to validate the method.

[1]  J. Kenner,et al.  LXIV.—A second form of 6 : 6′-dinitrodiphenic acid, and its conversion into new cyclic systems , 1921 .

[2]  L. Pu 1,1'-Binaphthyl-Based Chiral Materials: Our Journey , 2009 .

[3]  A. Ganong,et al.  Functional characterization of CP-465,022, a selective, noncompetitive AMPA receptor antagonist , 2002, Neuropharmacology.

[4]  F. Menniti,et al.  Quinazolin-4-one alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonists: structure-activity relationship of the C-2 side chain tether. , 2001, Journal of medicinal chemistry.

[5]  O. Hucke,et al.  Revealing Atropisomer Axial Chirality in Drug Discovery , 2011, ChemMedChem.

[6]  R. Adams,et al.  The Stereochemistry of Diphenyls and Analogous Compounds. , 1933 .

[7]  S. LaPlante,et al.  The challenge of atropisomerism in drug discovery. , 2009, Angewandte Chemie.

[8]  Xumu Zhang,et al.  New chiral phosphorus ligands for enantioselective hydrogenation. , 2003, Chemical reviews.

[9]  Takao Saito,et al.  Recent Advances in Biaryl-Type Bisphosphine Ligands , 2005 .

[10]  A. Ganong,et al.  Atropisomeric quinazolin-4-one derivatives are potent noncompetitive alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonists. , 2001, Bioorganic & medicinal chemistry letters.

[11]  A. Ganong,et al.  Is Not Neuroprotective In Vivo CP-465 , 022 , a Selective Noncompetitive AMPA Receptor Antagonist , Blocks AMPA , 2002 .

[12]  O. Hucke,et al.  Assessing atropisomer axial chirality in drug discovery and development. , 2011, Journal of medicinal chemistry.

[13]  Marc Lemaire,et al.  Modified BINAP: the how and the why. , 2005, Chemical reviews.

[14]  Timothy F. Jamison,et al.  Continuous flow multi-step organic synthesis , 2010 .

[15]  V. Sekhar,et al.  Determination of the activation parameters and the mechanism for atropisomerization of (S)-3-(2-chlorophenyl)-2-[2-(6-diethylaminomethylpyridin-2-yl)vinyl]-6-fluoroquinazolin-4(3H)-one , 2001 .