ABSTRACT
Glycogen synthase kinase-3 (GSK-3) regulates multiple cellular processes in diabetes, oncology, and neurology. N-(3-(1H-1,2,4-triazol-1-yl)propyl)-5-(3-chloro-4-methoxyphenyl)oxazole-4-carboxamide (PF-04802367 or PF-367) has been identified as a highly potent inhibitor, which is among the most selective antagonists of GSK-3 to date. Its efficacy was demonstrated in modulation of tau phosphorylation inâ vitro and inâ vivo. Whereas the kinetics of PF-367 binding in brain tissues are too fast for an effective therapeutic agent, the pharmacokinetic profile of PF-367 is ideal for discovery of radiopharmaceuticals for GSK-3 in the central nervous system. A (11) C-isotopologue of PF-367 was synthesized and preliminary PET imaging studies in non-human primates confirmed that we have overcome the two major obstacles for imaging GSK-3, namely, reasonable brain permeability and displaceable binding.
Subject(s)
Brain/drug effects , Brain/diagnostic imaging , Neuroimaging , Oxazoles/pharmacology , Positron-Emission Tomography , Protein Kinase Inhibitors/pharmacology , Triazoles/pharmacology , tau Proteins/antagonists & inhibitors , Brain/metabolism , Crystallography, X-Ray , Dose-Response Relationship, Drug , Glycogen Synthase Kinase 3/antagonists & inhibitors , Glycogen Synthase Kinase 3/metabolism , Humans , Models, Molecular , Molecular Structure , Oxazoles/chemical synthesis , Oxazoles/chemistry , Phosphorylation/drug effects , Protein Kinase Inhibitors/chemical synthesis , Protein Kinase Inhibitors/chemistry , Triazoles/chemical synthesis , Triazoles/chemistry , tau Proteins/metabolismABSTRACT
Single enantiomer (SS) and (RR) 2-[(phenoxy)(phenyl)methyl]morpholine derivatives 5, 8-23 are inhibitors of monoamine reuptake. Target compounds were prepared using an enantioselective synthesis employing a highly specific enzyme-catalysed resolution of racemic n-butyl 4-benzylmorpholine-2-carboxylate (26) as the key step. Structure-activity relationships established that serotonin and noradrenaline reuptake inhibition are functions of stereochemistry and aryl/aryloxy ring substitution. Consequently, selective SRI, selective NRI and dual SNRIs were all identified. One of these compounds, a potent and selective dual SNRI, (SS)-5a was selected as a candidate for further pre-clinical evaluation.
Subject(s)
Drug Design , Morpholines/chemical synthesis , Morpholines/pharmacology , Norepinephrine/metabolism , Serotonin/metabolism , Cells, Cultured , Humans , Liver/drug effects , Liver/metabolism , Molecular Structure , Morpholines/chemistry , Selective Serotonin Reuptake Inhibitors/chemical synthesis , Selective Serotonin Reuptake Inhibitors/chemistry , Selective Serotonin Reuptake Inhibitors/pharmacology , Stereoisomerism , Structure-Activity RelationshipABSTRACT
The Type 1 PI3Kinases comprise a family of enzymes, which primarily phosphorylate PIP2 to give the second messenger PIP3, a key player in many intracellular signaling processes [Science, 2002, 296, 1655; Trends Pharmacol. Sci.2003, 24, 366]. Of the four type 1 PI3Ks, the gamma-isoform, which is expressed almost exclusively in leukocytes [Curr. Biol., 1997, 7, R470], is of particular interest with respect to its role in inflammatory diseases such as rheumatoid arthritis (RA) and chronic obstructive pulmonary disease (COPD) [Mol. Med. Today, 2000, 6, 347]. Investigation of a series of 4,6-disubstituted-4H-benzo[1,4]oxazin-3-ones has led to the identification of single-digit nanomolar inhibitors of PI3Kgamma, several of which had good cell based activity and were shown to be active in vivo in an aspectic peritonitis model of inflammatory cell migration.