Development of dual V1a/V2 antagonists containing triazolobenzazepine scaffold.

The development of a dual V1a/V2 antagonist compound is a complex and challenging task. Conivaptan is up to now the only known V1a/V2 antagonist which was approved for the treatment of euvolemic hyponatremia. Previously, we reported RGH-122, a novel selective V1a antagonist compound.

Discovery and Characterization of RGH-122, a Potent, Selective, and Orally Bioavailable V1a Receptor Antagonist.

The V1a receptor is a major contributor in mediating the social and emotional effects of arginine-vasopressin (AVP); therefore it represents a promising target in the treatment of several neuropsychiatric conditions. The aim of this research was to design and synthesize novel and selective V1a antagonists with improved and profiles. Through optimization and detailed SAR studies, we developed low nanomolar antagonists, and further characterizations led to the discovery of the clinical candidate compound (RGH-122).

Identification of Triazolopyridines as Selective α5-GABA Receptor Negative Allosteric Modulators by a Hybridization Approach.

The identification and characterization of novel triazolopyridine derivatives with selective α5 subunit-containing GABA receptor negative allosteric modulator (NAM) activity are disclosed. As a result of screening of our corporate compound deck, we identified a moderately potent hit that was converted to an advanced hit bearing better physicochemical and pharmacological properties using a hybridization approach. Subsequent optimization led to the identification of potent and subtype-selective α5-GABA receptor NAMs representing a new chemotype in this area.

Synthesis and Characterization of New V Antagonist Compounds: The Separation of Four Atropisomeric Stereoisomers.

A new class of selective vasopressin receptor 1A (V) antagonists was identified, where "methyl-scan" was performed around the benzene ring of the 5-hydroxy-triazolobenzazepine core. This led to the synthesis of two 10-methyl derivatives, each possessing a chiral axis and a stereogenic center. The four atropisomeric stereoisomers (involving two enantiomer pairs and atropisomeric diastereomers) could be successfully isolated and spectroscopically characterized.

Structure of the major degradant of ezetimibe.

In a recent contribution to this Journal Gajjar and Shah described the isolation and structure elucidation of the major alkaline degradant of ezetimibe, a lipid lowering agent [A.K. Gajjar, V.

Chemical and biological investigation of cyclopropyl containing diaryl-pyrazole-3-carboxamides as novel and potent cannabinoid type 1 receptor antagonists.

Obesity is a major clinical problem in the western world, and many molecular targets have been explored in the search for effective therapeutic agents. One of these, antagonism of the cannabinoid 1 (CB1) receptor, rose to prominence following reports demonstrating the positive modulation of food intake by the CB1 antagonist, rimonabant (3) (SR141716A). In the present study, various diaryl-pyrazole derivatives containing cycloalkyl building blocks were synthesized and tested for CB1 receptor binding affinities.

Hit-to-lead optimization of pyrrolo[1,2-a]quinoxalines as novel cannabinoid type 1 receptor antagonists.

Hit-to-lead optimization of a novel series of N-alkyl-N-[2-oxo-2-(4-aryl-4H-pyrrolo[1,2-a]quinoxaline-5-yl)-ethyl]-carboxylic acid amides, derived from a high throughput screening (HTS) hit, are described. Subsequent optimization led to identification of in vitro potent cannabinoid 1 receptor (CB1R) antagonists representing a new class of compounds in this area.

Nitrone derivatives of trolox as neuroprotective agents.

Synthesis of nitrone derivatives of trolox is described. Their biological evaluation was performed in vitro for scavenging different free radicals, inhibiting Fe(2+)-induced lipid peroxidation, and in vivo in a permanent middle cerebral artery occlusion model in mice. New compounds exert pharmacological activities comparable to or better than those of trolox or nitrone-type reference compounds.