This compound, N-(3-Aminopropyl)-2-nitrobenzenesulfonamide Hydrochloride, is a mono-protected derivative of 1,3-diaminopropane, where one primary amine is protected as a nosyl (2-nitrobenzenesulfonamide) group. It serves as a versatile building block in organic synthesis, enabling selective functionalization at the unprotected primary amine terminus while keeping the other amine masked. The nosyl protecting group is orthogonally removable under mild conditions, such as with thiophenol or other nucleophiles, facilitating deprotection in multi-step sequences. This makes it particularly valuable in the synthesis of pharmaceuticals, peptide conjugates, and other bioactive molecules requiring precise control over amine reactivity.