Discovery of a Novel Class of Phosphodiesterase 10A Inhibitors and Identification of Clinical Candidate 2-[4-(1-Methyl-4-pyridin-4-yl-1 H -pyrazol-3-yl)-phenoxymethyl]-quinoline (PF-2545920) for the Treatment of Schizophrenia † † Coordinates of the PDE10A crystal structures have been deposited in the Protein Data Bank for compound 1 (3HQW), 2 (3HQY), 3 (3HQW) and 9 (3HR1).