H-D-allo-Thr(tBu)-OH is a non-natural, tert-butyl-protected derivative of the amino acid threonine, specifically in the D-allo stereoisomeric configuration. It features a chiral structure with two stereocenters, defined as (2R,3R), and contains both an amino group and a tert-butyl-protected β-hydroxy group on its side chain. This compound is a crucial chiral building block in pharmaceutical research and development. Its primary application is as a key intermediate in the solid-phase peptide synthesis (SPPS) of complex peptides and peptidomimetics. The tert-butyl (tBu) group serves as a robust protecting group for the side-chain hydroxyl, preventing unwanted side reactions during peptide chain elongation. The specific D-allo configuration is essential for constructing peptides with precise three-dimensional structures, which is critical for modulating biological activity, stability, and receptor binding affinity in therapeutic candidates. As a high-purity, specialty amino acid derivative, it is primarily used in the synthesis of bioactive peptides for drug discovery, particularly in areas like oncology, metabolic diseases, and antimicrobial agents. It is a standard reagent supplied by fine chemical and peptide synthesis vendors for research purposes.