Palladium-catalyzed cross-coupling reactions for the synthesis of 6,8-disubstituted 1,7-naphthyridines: A novel class of potent and selective phosphodiesterase type 4D inhibitors
JOURNAL OF MEDICINAL CHEMISTRY
Authors: Hersperger, R; Bray-French, K; Mazzoni, L; Muller, T
Abstract
Recently, four subtypes of the human phosphodiesterase type 4 (PDE4A-D) enzyme have been described. So far, only very few PDE4 subtype-selective inhibitors are known. Herein; we describe the synthesis of 6,8-disubstituted 1,7-naphthyridines and their characterization as potent and selective inhibitors of PDE4D which suppress the oxidative burst in human eosinophils with IC50 values as low as 0.7 nM. SAR development and the extended use of palladium-catalyzed cross-coupling reactions led to compound 11 which inhibited human PDE4D T-Vith an IC50 value of 1 nM. Thus, compound II was 55, 175, and 1000 times more potent in inhibiting PDE4D over PDE4B, PDE4A, sind PDE4C. In a Brown Norway rat model of allergic asthma, compound 11 when given by the oral route (1 mg/kg) reduced by more than 50% the influx of eosinophils, T-cells, and neutrophils into bronchoalveolar lavage fluid (BALF) samples obtained from antigen-challenged animals. Thus, PDE4D-selective inhibitors of the 1.,7-naphthyridine class have the potential as an oral therapy for treating asthma.
Dissecting DISC1 function through protein-protein interactions
BIOCHEMICAL SOCIETY TRANSACTIONS
Authors: Brandon, N. J.
Abstract
Disrupted in schizophrenia 1 (DISC1) is emerging in the eyes of many as the most promising candidate of all the schizophrenia risk genes. This viewpoint is derived from the combination of genetic, clinical, imaging and rapidly advancing cell biology data around this gene. All of these areas have been reviewed extensively recently and this review will point you towards some of these excellent papers. My own personal view of the potential importance of DISC1 was echoed in a recent review which suggested that DISC1 may be a 'Rosetta Stone' for schizophrenia research [Ross, Margolis, Reading, Pletnikov and Coyle (2006) Neuron 52, 139-153]. Our own efforts to try to understand the function of DISC1 were through identification of its protein-binding partners. Through an extensive Y2H (yeast two-hybrid) and bioinformatics effort we generated the 'DISC1-Interactome', a comprehensive network of protein-protein interactions around DISC1. In two excellent industry-academia collaborations we focused on two main interacting partners: Ndel1 (nudE nuclear distribution gene E homologue-like 1), an enigmatic protein which may have diverse functions as both a cysteine protease and a key centrosomal structural protein; and PDE4B. a cAMP-specific phosphodiestefase. I will review the work around these two protein complexes in detail.