Publications by authors named "James F Dropinski"

Prochiral hydrazones undergo efficient and highly selective hydrogenation in the presence of a chiral diphosphine ruthenium catalyst, yielding enantioenriched hydrazine products (up to 99% ). The mild reaction conditions and broad functional group tolerance of this method allow access to versatile chiral hydrazine building blocks containing aryl bromide, heteroaryl, alkyl, cycloalkyl, and ester substituents. This method was also demonstrated on >150 g scale, providing a valuable hydrazine intermediate en route to an active pharmaceutical ingredient.

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Aliphatic amines, oxygenated at remote positions within the molecule, represent an important class of synthetic building blocks to which there are currently no direct means of access. Reported herein is an efficient and scalable solution that relies upon decatungstate photocatalysis under acidic conditions using either H O or O as the terminal oxidant. By using these reaction conditions a series of simple and unbiased aliphatic amine starting materials can be oxidized to value-added ketone products.

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Major new advances in synthetic chemistry methods are typically reported using simple, non-standardized reaction substrates, and reaction failures are rarely documented. This makes the evaluation and choice of a synthetic method difficult. We report a standardized complex molecule diagnostic approach using collections of relevant drug-like molecules which we call chemistry informer libraries.

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Semi-synthetic water-soluble analogs were synthesized from nocathiacin I through the formation of a versatile intermediate nocathiacin amine 5, and subsequent transformation via reductive amination, acylation or urea formation. Several of the novel analogs displayed much improved aqueous solubility over 1, while retained antibacterial activity. Compound 15 and 16 from the amide series, demonstrated excellent in vitro and in vivo antibacterial activity.

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Novel water-soluble amide analogs were synthesized from nocathiacin I (1) through the formation of the carboxylic acid intermediate followed by coupling to primary or secondary amines. Several compounds with potent antibacterial activity and adequate water solubility were identified. Of these, compound 19 was selected for more extensive evaluation because of its excellent in vitro antibacterial activity and in vivo efficacy, as well as clean off-target screening.

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A series of novel aryl indole-2-carboxylic acids has been identified as potent selective PPARgamma modulators. Their chemical synthesis and in vitro activities are discussed. Compound 5 was selected for in vivo testing in the db/db mouse model of type 2 diabetes and resulted in reduction of hyperglycemia at comparable plasma exposure when compared to rosiglitazone.

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The design and synthesis of a novel class of 2,3-dihydrobenzofuran-2-carboxylic acids as highly potent and subtype-selective PPARalpha agonists are reported. Systematic study of structure-activity relationships has identified several key structural elements within this class for maintaining the potency and subtype selectivity. Select compounds were evaluated in animal models of dyslipidemia using Syrian hamsters and male Beagle dogs, and all these compounds displayed excellent cholesterol- and triglyceride-lowering activity at dose levels that were much lower than the marketed weak PPARalpha agonist fenofibrate.

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The synthesis and structure-activity relationships of novel series of alpha-aryloxyphenylacetic acids as PPARalpha/gamma dual agonists are reported. The initial search for surrogates of the ester group in the screen lead led first to the optimization of a subseries with a ketone moiety. Further efforts to modify the ketone subseries led to the design and synthesis of two new subseries containing fused heterocyclic ring systems.

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