Kurt A. Josef

Subsite requirements for peptide aldehyde inhibitors of human calpain I

Abstract Dipeptide and tripeptide aldehydes have been evaluated as inhibitors of human calpain I. Dipeptide aldehydes are generally equipotent with tripeptide aldehydes. Calpain I possesses a rather stringent requirement for Leu at P2, but accepts a variety of capping groups and amino acids at P1 and P3. Several new peptide aldehydes that are more potent than previously reported calpain I inhibitors have been identified.

Mixed-lineage kinase 1 and mixed-lineage kinase 3 subtype-selective dihydronaphthyl[3,4-a]pyrrolo[3,4-c]carbazole-5-ones: optimization, mixed-lineage kinase 1 crystallography, and oral in vivo activity in 1-methyl-4-phenyltetrahydropyridine models.

The optimization of the dihydronaphthyl[3,4-a]pyrrolo[3,4-c]carbazole-5-one R(2) and R(12) positions led to the identification of the first MLK1 and MLK3 subtype-selective inhibitors within the MLK family. Compounds 14 (CEP-5104) and 16 (CEP-6331) displayed good potency for MLK1 and MLK3 inhibition with a greater than 30- to 100-fold selectivity for related family members MLK2 and DLK. Compounds 14 and 16 were orally active in vivo in a mouse MPTP biochemical efficacy model that was comparable to the first-generation pan-MLK inhibitor 1 (CEP-1347). The MLK1 structure-activity relationships were supported by the first-reported X-ray crystal structure of MLK1 bound with 16.

Identification of pyridazin-3-one derivatives as potent, selective histamine H3 receptor inverse agonists with robust wake activity

H(3)R structure-activity relationships on a novel class of pyridazin-3-one H(3)R antagonists/inverse agonists are disclosed. Modifications of the pyridazinone core, central phenyl ring and linker led to the identification of molecules with excellent target potency, selectivity and pharmacokinetic properties. Compounds 13 and 21 displayed potent functional H(3)R antagonism in vivo in the rat dipsogenia model and demonstrated robust wake activity in the rat EEG/EMG model.

Potent fluoromethyl ketone inhibitors of recombinant human calpain I

Abstract We report on a series of potent and selective dipeptide fluoromethyl ketone inhibitors of recombinant human calpain I. Compound 4f, having a tetrahydroisoquinoline containing urea motif as N-terminus capping group, is the most potent member ( k obs I = 276,000 M−1 s−1) of this class. This compound was shown to prefer calpain I by >36-fold and approximately 4-fold over the related cysteine proteases, cathepsin B and cathepsin L, respectively.

4-Phenoxypiperidine pyridazin-3-one histamine H3 receptor inverse agonists demonstrating potent and robust wake promoting activity

Structure-activity relationships for a series of phenoxypiperidine pyridazin-3-one H(3)R antagonists/inverse agonists are disclosed. The search for compounds with improved hERG and DAT selectivity without the formation of in vivo active metabolites identified 6-[4-(1-cyclobutyl-piperidin-4-yloxy)-phenyl]-4,4-dimethyl-4,5-dihydro-2H-pyridazin-3-one 17b. Compound 17b met discovery flow criteria, demonstrated potent H(3)R functional antagonism in vivo in the rat dipsogenia model and potent wake activity in the rat EEG/EMG model at doses as low as 0.1 mg/kg ip.

4,5-Dihydropyridazin-3-one derivatives as histamine H3 receptor inverse agonists

H(3)R structure-activity relationships for a new class of 4,5-dihydropyridazin-3-one H(3)R antagonists/inverse agonists are disclosed. Modification of the 4,5-dihydropyridazinone moiety to block in vivo metabolism identified 4,4-dimethyl-6-{4-[3-((R)-2-methyl-pyrrolidin-1-yl)-propoxy]-phenyl}-4,5-dihydro-2H-pyridazin-3-one 22 as a lead candidate demonstrating potent in vivo functional H(3)R antagonism in the rat dipsogenia model and robust wake promoting activity in the rat EEG/EMG model.

TIE-2/VEGF-R2 SAR and in vitro activity of C3-acyl dihydroindazolo[5,4-a]pyrrolo[3,4-c]carbazole analogs.

Orally bioavailable, dual inhibitors of TIE-2/VEGF-R2 were identified by elaborating the C3/N13 SAR around a fused pyrrolodihydroindazolocarbazole scaffold. Analogs bearing a C3-thiophencarbonyl group were evaluated in enzymatic and cellular biochemical assays; two orally bioavailable analogs were further profiled in functional assays and found to inhibit microvessel growth in rat aortic explant cultures and inhibit Ang-1-stimulated chemotaxis of HUVECs.

Pyrazole trk kinase inhibitors for the treatment of cancer

Two related applications from AstraZeneca claim novel pyrazole derivatives and their process for preparation as trk kinase inhibitors for use in oncology. The compounds are claimed for stand-alone or combination therapy. The two series, which differ by position of attachment of the pyrazole group, are prepared from a common intermediate by reversing the order of the aminopyrazole step. TrkA kinase data are provided for three examples in each application.

Synthesis of constrained benzocinnolinone analogues of CEP-26401 (irdabisant) as potent, selective histamine H3 receptor inverse agonists.

A novel class of benzocinnolinones analogs of irdabisant were designed and synthesized as histamine H3R antagonists/inverse agonists. Modifications to the pyridazinone portion of the core and linker led to the identification of molecules with excellent target potency and selectivity with improved rat pharmacokinetic properties and reduced potential hERG liabilities.

1-Phenyl-2-pyrrolidinyl-cyclopentylamine via Thermal Rearrangement

Abstract Thermal rearrangement of aminoimine, 1, followed by hydrogenation produced 1-phenyl-2-pyrrolidinyl cyclopentylamine 3. The structure and stereochemistry of this novel amine 4 was identified by x-ray crystallography of the 2-chloro-6-iodo-nicotinamide derivative as a hydrogen maleate salt.