Tina Morgan Ross

Discovery of RG7388, a Potent and Selective p53–MDM2 Inhibitor in Clinical Development

Restoration of p53 activity by inhibition of the p53-MDM2 interaction has been considered an attractive approach for cancer treatment. However, the hydrophobic protein-protein interaction surface represents a significant challenge for the development of small-molecule inhibitors with desirable pharmacological profiles. RG7112 was the first small-molecule p53-MDM2 inhibitor in clinical development. Here, we report the discovery and characterization of a second generation clinical MDM2 inhibitor, RG7388, with superior potency and selectivity.

2,3-Dihydro-dithiin and -dithiepine-1,1,4,4-tetroxides: small molecule non-peptide antagonists of the human galanin hGAL-1 receptor

The neuropeptide galanin modulates several physiological functions such as cognition, learning, feeding behavior, and depression, probably via the galanin 1 receptor (GAL-R1). Using an HTS assay based on 125I-human galanin binding to the human galanin-1 receptor (hGAL-R1), we discovered a series of 1,4-dithiin and dithiipine-1,1,4,4-tetroxides that exhibited binding affinity IC50s to hGAL-R1 ranging from 190 to 2700 nM. Two of the dithiepin analogues, 7 and 23, behaved pharmacologically as hGAL-R1 antagonists in secondary assays involving adenylate cyclase activity and GTP binding to G-proteins. Analogues 7 and 23 were also active in functional assays involving galanin, reversing the inhibitory effect of galanin on acetylcholine (ACh) release in rat brain hippocampal slices and electrically-stimulated guinea pig ileum twitch.

Structural and stereochemical requirements of time-dependent inactivators of the interleukin-1β converting enzyme

Abstract Structural and stereochemical requirements of substrate based time-dependent inactivators of interleukin-1β converting enzyme were investigated. Hydrophobic amino acids with L-stereochemistry are preferred at the P 2 and P 3 positions. It appears that both D-and L-Asp are accepted by the enzyme at the P I position.

Structure activity relationships of non-peptide bradykinin B2 receptor antagonists

Abstract A series of non-peptide competitive antagonists of the human IMR 90 fetal lung fibroblast bradykinin B2 receptor have been designed and synthesized. Compound 15 binds with an affinity constant Ki = 60 nM. The SAR leading to the design of these non-peptide antagonists is described.

3-chloro-4-carboxamido-6-arylpyridazines as a non-peptide class of interleukin-1β converting enzyme inhibitor

Abstract The 3-chloro-4-carboxamido-6-arylpyridazines are a novel class of interleukin-1β converting enzyme (ICE) inhibitor. These agents are irreversible inhibitors with pyridazine 23 possessing a k obs [I] = 355 M−1s−1. A structure-activity relationship for this non-peptide class of compounds and the putative mechanism for irreversible inactivation are described.

A selective small molecule NOP (ORL-1 receptor) partial agonist for the treatment of anxiety

Small molecule (1) has been identified as a selective partial agonist of Opioid Receptor Like-1 (ORL-1) with potential utility for the treatment of anxiety and other disorders. Nociceptin (orphanin FQ) is an endogenous peptide ligand that binds to ORL-1, however it does not bind the classical δ, μ and κ opioid receptors with high affinity. The synthesis of 1 involved using a molecular diversity approach, to rapidly advance a library of compounds for biological testing. A lead selective potent partial agonist (35-fold ORL-1/Mu) progressed to ORL-1 (NOP or OP4) proof of concept testing in advanced studies. The synthetic approach and biological data for the related chemical series will be presented.