Anil Patel

Optimization of a Series of Bivalent Triazolopyridazine Based Bromodomain and Extraterminal Inhibitors: The Discovery of (3R)-4-[2-[4-[1-(3-Methoxy-[1,2,4]triazolo[4,3-b]pyridazin-6-yl)-4-piperidyl]phenoxy]ethyl]-1,3-dimethyl-piperazin-2-one (AZD5153)

Here we report the discovery and optimization of a series of bivalent bromodomain and extraterminal inhibitors. Starting with the observation of BRD4 activity of compounds from a previous program, the compounds were optimized for BRD4 potency and physical properties. The optimized compound from this campaign exhibited excellent pharmacokinetic profile and exhibited high potency in vitro and in vivo effecting c-Myc downregulation and tumor growth inhibition in xenograft studies. This compound was selected as the development candidate, AZD5153. The series showed enhanced potency as a result of bivalent binding and a clear correlation between BRD4 activity and cellular potency.

Switching between agonists and antagonists at CRTh2 in a series of highly potent and selective biaryl phenoxyacetic acids

A novel series of biaryl phenoxyacetic acids was discovered as potent, selective antagonists of the chemoattractant receptor-homologous expressed on Th2 lymphocytes receptor (CRTh2 or DP2). A hit compound 4 was discovered from high throughput screening. Modulation of multiple aryl substituents afforded both agonists and antagonists, with small changes often reversing the mode of action. Understanding the complex SAR allowed design of potent antagonists such as potential candidate 34.

Zwitterionic CRTh2 Antagonists

A novel series of zwitterions is reported that contains potent, selective antagonists of the chemoattractant receptor-homologous expressed on Th2 lymphocytes receptor (CRTh2 or DP2). A high quality lead compound 2 was discovered from virtual screening based on the pharmacophore features present in a literature compound 1. Lead optimization through side chain modification and preliminary changes around the acid are disclosed. Optimization of physicochemical properties (log D, MWt, and HBA) allowed maintenance of high CRTh2 potency while achieving low rates of metabolism and minimization of other potential concerns such as hERG channel activity and permeability. A step-change increase in potency was achieved through addition of a single methyl group onto the piperazine ring, which gave high quality compounds suitable for progression into in vivo studies.