– Tri-GalNAc-NHS ester is a LYsosome TArgeting Chimera (LYTAC) and a ligand of asialoglycoprotein receptor (ASGPR). ASGPR is a lysosomal targeting receptor specifically expressed on liver cells, for the degradation of extracellular proteins including membrane proteins. Tri-GalNAc-NHS ester can be used as a protein degrader and it can be used for the research of LYTAC.