21636-17-9

Upstream product

• 321-14-2 5-chloro-2-hydroxybenzoic acid 
• 88-74-4 2-nitro-aniline 
• 15216-81-6 5-chloro-2-hydroxybenzoyl chloride 

Relevant academic research and scientific papers

Application of niclosamide and analogs as small molecule inhibitors of Zika virus and SARS-CoV-2 infection

Zika virus has emerged as a potential threat to human health globally. A previous drug repurposing screen identified the approved anthelminthic drug niclosamide as a small molecule inhibitor of Zika virus infection. However, as antihelminthic drugs are generally designed to have low absorption when dosed orally, the very limited bioavailability of niclosamide will likely hinder its potential direct repurposing as an antiviral medication. Here, we conducted SAR studies focusing on the anilide and salicylic acid regions of niclosamide to improve physicochemical properties such as microsomal metabolic stability, permeability and solubility. We found that the 5-bromo substitution in the salicylic acid region retains potency while providing better drug-like properties. Other modifications in the anilide region with 2′-OMe and 2′-H substitutions were also advantageous. We found that the 4′-NO2 substituent can be replaced with a 4′-CN or 4′-CF3 substituents. Together, these modifications provide a basis for optimizing the structure of niclosamide to improve systemic exposure for application of niclosamide analogs as drug lead candidates for treating Zika and other viral infections. Indeed, key analogs were also able to rescue cells from the cytopathic effect of SARS-CoV-2 infection, indicating relevance for therapeutic strategies targeting the COVID-19 pandemic.

Identification and synthesis of low-molecular weight cholecystokinin B receptor (CCKBR) agonists as mediators of long-term synaptic potentiation

Recently, He et al. reported that CCKB receptors located in the neocortex of the brain when bound to their bound natural ligand, CCK peptides, enhance memory, bringing up the possibility that agonists targeting the CCKB receptor may act as therapeutic agents in diseases in which memory loss is marked as observed in dementia and Alzheimer’s. In this report, we describe the synthesis of novel low-molecular weight benzoamine CCKB receptor agonists. The compounds made in this series were determined to be mostly partial agonists, although some antagonists were identified, as well, capable of triggering calcium release in a cell line that overexpresses the CCKB receptor. Compound 35 demonstrated an EC50 of 0.15 μM in the cell-based assay, but more importantly, several of the compounds, including 35, demonstrated a physiological effect, inducing long-term potentiation in rat brains comparable to the CCK-8 peptide albeit at much higher concentrations. Based on these findings, benzoamines may be the basis for a new series of CCKB receptor agonists in drug-discovery efforts that seek to develop therapeutics to prevent memory loss.

Small molecule modulators of Wnt/β-catenin signaling

The Wnt signal transduction pathway is dysregulated in many highly prevalent diseases, including cancer. Unfortunately, drug discovery efforts have been hampered by the paucity of targets and drug-like lead molecules amenable to drug discovery. Recently, we reported the FDA-approved anthelmintic drug Niclosamide inhibits Wnt/β-catenin signaling by a unique mechanism, though the target responsible remains unknown. We interrogated the mechanism and structure-activity relationships to understand drivers of potency and to assist target identification efforts. We found inhibition of Wnt signaling by Niclosamide appears unique among the structurally-related anthelmintic agents tested and found the potency and functional response was dependent on small changes in the chemical structure of Niclosamide. Overall, these findings support efforts to identify the target of Niclosamide inhibition of Wnt/β-catenin signaling and the discovery of potent and selective modulators to treat human disease.