This test case illustrates the use of the classification notebook and functions of PythiaCHEM by assessing the ability of various classifiers to predict the transport activity of synthetic anion transporters. The transport activity is experimentally measured by EC 50 , which indicates the concentration of transporter required to obtain 50% chloride efflux (in mol% transporter to lipid). We collected transport activity data from the literature that have been measured using an ion-selective electrode (ISE) assay, which measures chloride efflux from large unilamellar vesicles (LUVs), through a chloride/nitrate exchange mechanism. Our dataset comprises 304 using SMOTEN. The dataset was temporally split, with data from 2021 serving as the test set (44 data points) and earlier years (260 data points) as the training set.