Structure–activity relationship studies of salubrinal lead to its active biotinylated derivative

The synthesis and structure–activity relationships (SAR) of salubrinal, a small molecule that protects cells from apoptosis induced by endoplasmic reticulum (ER) stress, are described. It is revealed that the trichloromethyl group greatly contributes to the activity. Based on the SAR results, salubrinal was converted into a biotinylated derivative which retains activity and can be used as a biological tool for target identification.