ABSTRACT
Accumulation of beta-amyloid (Abeta), produced by the proteolytic cleavage of amyloid precursor protein (APP) by beta- and gamma-secretase, is widely believed to be associated with Alzheimer's disease (AD). Research around the high-throughput screening hit (S)-4-chlorophenylsulfonyl isoleucinol led to the identification of the Notch-1-sparing (9.5-fold) gamma-secretase inhibitor (S)-N-(5-chlorothiophene-2-sulfonyl)-beta,beta-diethylalaninol 7.b.2 (Abeta(40/42) EC(50)=28 nM), which is efficacious in reduction of Abeta production in vivo.
Subject(s)
Alzheimer Disease/drug therapy , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Isoleucine/analogs & derivatives , Receptor, Notch1/metabolism , Alcohols , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Protein Precursor/chemistry , Animals , Drug Design , Humans , Isoleucine/chemistry , Models, Chemical , Propanolamines/chemistry , Sulfonamides/chemistryABSTRACT
SAR on HTS hits 1 and 2 led to the potent, Notch-1-sparing GSI 9, which lowered brain Abeta in Tg2576 mice at 100 mg/kg po. Converting the metabolically labile methyl groups in 9 to trifluoromethyl groups afforded the more stable analogue 10, which had improved in vivo potency. Further side chain modification afforded the potent Notch-1-sparing GSI begacestat (5), which was selected for development for the treatment of Alzheimer's disease.
Subject(s)
Alzheimer Disease/drug therapy , Amyloid Precursor Protein Secretases/antagonists & inhibitors , Drug Discovery , Enzyme Inhibitors/pharmacology , Receptor, Notch1/metabolism , Sulfonamides/pharmacology , Thiophenes/pharmacology , Alzheimer Disease/enzymology , Amyloid Precursor Protein Secretases/metabolism , Amyloid beta-Peptides/metabolism , Animals , Crystallography, X-Ray , Disease Models, Animal , Dose-Response Relationship, Drug , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Mice , Mice, Transgenic , Models, Molecular , Molecular Conformation , Stereoisomerism , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/chemistry , Thiophenes/chemical synthesis , Thiophenes/chemistryABSTRACT
Using a cell-based assay, we have identified a new series of Notch-sparing gamma-secretase inhibitors from HTS screening leads 2a and 2e. Lead optimization studies led to the discovery of analog 8e with improved gamma-secretase inhibitory potency and Notch-sparing selectivity.
Subject(s)
Amyloid Precursor Protein Secretases/antagonists & inhibitors , Chemistry, Pharmaceutical/methods , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/pharmacology , Receptors, Notch/metabolism , Alzheimer Disease/drug therapy , Amyloid/chemistry , Amyloid Precursor Protein Secretases/chemistry , Carbon/chemistry , Drug Design , Drug Evaluation, Preclinical , Humans , Models, Chemical , Receptors, Notch/antagonists & inhibitors , Structure-Activity RelationshipABSTRACT
An asymmetric synthesis of alpha-amino acids with novel beta-branched side chains has been implemented. The syntheses feature a p-toluenesulfinylimine induced chiral Strecker approach and were found to be applicable to the introduction of both aliphatic and aromatic beta-branched sidechains for preparation of previously unknown alpha-amino acids.