We previously introduced a cluster subprofile analysis which allows the classification of active compounds into currently 13 bioactivity clusters based on activity in the CPA. Application of this cluster analysis to the Enamine-PNPs which had displayed bioactivity in CPA at the two concentrations revealed that among the identified clusters lysosomotropism / cholesterol homeostasis, tubulin modulation and DNA synthesis inhibition are the most prominent activities (fig. ). The active Enamine-PNPs investigated here did not contain members that could be assigned to the Akt/PI3K/MTor, Aurora kinase, HSP90, Na + /K + -ATPase, protein synthesis, pyrimidine synthesis, and uncoupler clusters. Interestingly, 106 of the 143 Enamine-PNPs active at 30 µM (74%) could not be assigned to any cluster with a subprofile similarity o ≥ 80 (at 10 µM, 28 out of 44 active compounds (64%) could not be assigned).