The design and synthesis of peptides represent a sophisticated branch of organic chemistry, driven by the need for specific biological activities and therapeutic applications. At the heart of successful peptide synthesis lies the careful selection and utilization of protected amino acid building blocks. Among these, Boc-His(Tos)-OH, identified by its CAS number 35899-43-5, holds a significant position. This article explores the chemistry behind this vital compound and its indispensable role in modern peptide design, emphasizing the quality standards expected from a reputable manufacturer and supplier.

Boc-His(Tos)-OH is a derivative of L-histidine, an amino acid characterized by its imidazole side chain. The imidazole ring possesses unique chemical properties, including amphoteric behavior and nucleophilicity, which can complicate peptide synthesis if not adequately managed. To address this, Boc-His(Tos)-OH employs two critical protecting groups. The tert-butoxycarbonyl (Boc) group shields the alpha-amino terminus, rendering it unreactive during coupling reactions. This group is selectively removable under mild acidic conditions, a hallmark of the Boc SPPS strategy. Simultaneously, the p-toluenesulfonyl (Tos) group is strategically placed on the imidazole ring. This bulky, electron-withdrawing group effectively deactivates the imidazole nitrogen, preventing it from participating in unwanted nucleophilic attacks or side reactions during the peptide chain assembly. The choice of the Tosyl group is deliberate; it is stable under typical coupling and deprotection conditions of Boc SPPS but can be cleaved reliably in the final stages of synthesis, often alongside the removal of other acid-labile side-chain protecting groups.

For chemists and researchers looking to purchase Boc-His(Tos)-OH, understanding these chemical nuances is key to appreciating its value. The compound’s molecular formula is C18H23N3O6S, with a molecular weight of approximately 409.46 g/mol. Its structure is designed for optimal reactivity and selectivity in peptide coupling. When you buy this reagent from a trusted manufacturer, you ensure that the specified purity levels are met, minimizing the risk of incorporating incorrectly modified histidine residues into your target peptide sequence. The quest for high-purity intermediates like this is central to achieving efficient and reproducible synthetic outcomes.

As a leading chemical supplier specializing in amino acid derivatives, we are committed to providing Boc-His(Tos)-OH that meets the stringent demands of advanced peptide chemistry. Our manufacturing processes are optimized to ensure the integrity of both protecting groups and the chiral purity of the histidine backbone. We understand that price is a consideration, and we strive to offer competitive pricing for this essential building block. For those requiring bulk quantities or seeking a reliable supplier for ongoing projects, we are equipped to meet your needs. Contact us for a price quote and to learn more about how our high-quality Boc-His(Tos)-OH can enhance your peptide design and synthesis efforts.