The discovery of novel and highly potent oxopiperazine based B1 receptor antagonists is described. Compared to the previously described arylsulfonylated (R)-3-amino-3-phenylpropionic acid series, the current compounds showed improved in vitro potency and metabolic stability. Compound 17, 2-((2R)-1-((4-methylphenyl)sulfonyl)-3-oxo-2-piperazinyl)-N-((1R)-6-(1-piperidinylmethyl)-1,2,3,4-tetrahydro-1-naphthalenyl)acetamide, showed EC(50) of 10.
View Article and Find Full Text PDFHeteroarenes are important structural moieties in many chemical industry fields. A highly efficient Pd/Cu-catalyzed C-H arylation method for a range of heterocycles has been discovered. It was found that the key to the success of this transformation is a combination of a palladium catalyst and a well-defined copper cocatalyst.
View Article and Find Full Text PDFThe enantioselective conjugate addition of alkynyl nucleophiles has been a long-standing challenge in synthetic chemistry. This paper describes a highly practical asymmetric conjugate alkynylation of Meldrum's acid-derived acceptors using cinchonidine (<$100/kg) as the chiral mediator. The process provides practical access to chiral beta-alkynyl acids.
View Article and Find Full Text PDFTwo asymmetric syntheses of AMG 221 (2), an inhibitor of 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) discovered in our laboratories, are reported. One of the syntheses utilizes chiral trimethylsilyl cyanohydrin 12 as starting material and the other utilizes its enantiomer ent-12. The displacement approach involves the conversion of 12 to 2 via a six-step sequence, occurs with net inversion of configuration, and employs amine 6 as starting material.
View Article and Find Full Text PDFp38 MAP kinase inhibitors have attracted considerable interest as potential agents for the treatment of inflammatory diseases. Herein, we describe a concise and efficient synthesis of inhibitor 1 that is based on a phthalazine scaffold. Highlights of our approach include a practical synthesis of a 1,6-disubstituted phthalazine building block 24 as well as the one-pot formation of boronic acid 27.
View Article and Find Full Text PDFA diastereoselective palladium-catalyzed arylation of 4-substituted cyclohexyl esters has been developed. The reaction proceeds at room temperature in the presence of [(t-Bu3P)PdBr]2 providing products in up to 37:1 dr.
View Article and Find Full Text PDFA mild, one-pot synthesis of 4-quinolones is described. Under the optimal conditions, a variety of 2-substituted 4-quinolones were synthesized via sequential palladium-catalyzed amidation of 2'-bromoacetophenones followed by base-promoted intramolecular cyclization.
View Article and Find Full Text PDFSmall molecule TRPV1 antagonists have been a recent focus in the search for pain treatment agents. We herein describe a practical and scalable synthesis of AMG 628 (1), a bis-substituted pyrimidine derivative that was identified as a highly efficacious agent, suitable for clinical development. Highlights of our approach include a practical route to a substituted benzothiazole, a scalable synthesis of an enantiopure piperazine fragment, and identification of conditions for selective coupling reactions on 2,6-dichloropyrimidine, to access the active pharmaceutical ingredient in high purity and overall yield.
View Article and Find Full Text PDFTwo new methods for the synthesis of 2-aminothiazolones from 2-(4-methoxybenzylthio)acetic acids are described. A single reagent and simple experimental conditions are used in the key tandem deprotection-cyclization process. In the first approach 2-aminothiazolones are directly accessed via cyclization of the corresponding N-acylisothioureas.
View Article and Find Full Text PDFA one-pot procedure for the synthesis of 2-alkyl-2-arylcyanoacetates based on a Pd(OAc)2/DPPF (DPPF = 1,1'-diphenylphosphino ferreocene)-catalyzed enolate arylation followed by in situ alkylation has been developed. This procedure tolerates a diverse range of aryl and heteroaryl bromides, and provides a rapid entry to a variety of 2-alkyl-2-arylcyanoacetates in good to excellent yield.
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