4-(4-BOC-Piperazino)phenylboronic acid is a boronic acid derivative featuring a tert-butoxycarbonyl (Boc)-protected piperazine ring linked to a phenyl group. This bifunctional molecule combines a protected amine (piperazine) and an arylboronic acid group, making it a versatile building block in organic synthesis, particularly in cross-coupling reactions like the Suzuki-Miyaura reaction. Its primary application is as a key intermediate in pharmaceutical research and development. The Boc-protected piperazine moiety is a common pharmacophore found in numerous bioactive molecules, especially in central nervous system (CNS) and oncology drug candidates. The arylboronic acid handle allows for efficient introduction of this substituted phenylpiperazine fragment into more complex molecular architectures. It is frequently cited in patent literature for the synthesis of potential therapeutic agents, including kinase inhibitors and receptor modulators. As a specialized synthon, it is commercially available from fine chemical suppliers catering to medicinal chemistry. It requires standard handling precautions for boronic acids and should be stored under inert conditions to maintain stability.