A triantennary N-acetylgalactosamine (Tri-GalNAcβ) ligand presenting three β-GalNAc residues on a tris-based branched scaffold, extended through a β-alanine linker and a discrete, monodisperse triethylene glycol (PEG3) spacer to a terminal maleimide. The maleimide reacts selectively with free thiols, such as cysteine residues on proteins, peptides, or antibodies, to form stable thioether conjugates, providing a route to attach the Tri-GalNAc ligand to thiol-bearing payloads and surfaces. This compound enables the construction of hepatocyte-targeted therapeutics and research tools that exploit the asialoglycoprotein receptor (ASGPR; Ashwell-Morell receptor), which is highly expressed on liver hepatocytes and binds GalNAc-containing ligands with high affinity. The trivalent presentation of GalNAcβ residues engages multiple carbohydrate-recognition domains of ASGPR simultaneously, producing high-avidity binding that substantially exceeds the affinity of monovalent GalNAc ligands and closely mimics the geometry of clinically validated Tri-GalNAc targeting moieties used in approved GalNAc-siRNA therapeutics.