KRas4B G12D was incubated with the PhABit library (1 µM, 4 °C, 15 min, 200 µM PhABit) before irradiation and analysis by LC-MS. The results were compared to the screening of BRD4-BD1 and BCL6, to identify 11 unique hits for KRas, of which four were of particular interest (60-63, Figure ). These hits exemplified two chemotypes: 2-heterocyclic pyridines (60 and 61) and an indole warhead (62 and 63). The indoles are similar to previously reported KRas binders identified by NMR studies, suggesting the screen has identified true hits. The 2-heterocyclic pyridines do not resemble known ligands and therefore represent novel KRas binding motifs.