Idler Compounds: A Simple Protocol for Openly Sharing Fridge Contents for Cross-Screening

The first step in discovering novel medicines is identifying an initial hit against a biological target or organism, followed by extensive iterative processes to explore the structure-activity relationship and establish a lead compound. As a result, drug discovery laboratories tend to accumulate extensive collections of compounds with great potential value that merely reside in fridges and freezers. Cross screening these libraries against alternative targets holds significant potential for uncovering novel hits, but in the academic setting compound collections are rarely used in this way. We present a short guide for collecting small molecules not being actively pursued in group projects (which we term “idlers”) to establish an open compound library. We describe how a diverse subset of this library was screened against a panel of pathogens, with the resulting data made publicly available. We hope this work encourages other academic drug discovery groups to develop and share their own libraries of idlers, thereby maximising the utility of existing resources, enabling new insights, and catalysing novel research directions through open science.