2930.90.92.22 - N,N-Dialkyl (methyl, ethyl, n-propyl or isopropyl) aminoethane-2-thiols and their protonated salts, except for 2-(N,N- dimethylamino)ethanethiol and 2-(N,N- diethylamino)ethanethiol

This HTS classification, 2930.90.92.22, specifically addresses N,N-dialkyl (methyl, ethyl, n-propyl, or isopropyl) aminoethanethiols and their protonated salts. It is important to note that this category *excludes* two commonly known compounds: 2-(N,N-dimethylamino)ethanethiol and 2-(N,N-diethylamino)ethanethiol. These exclusions highlight the precise nature of this classification, focusing on specific structural variations within the broader group of aminoethanethiols.

This category distinguishes itself from its siblings by its exclusive focus on the aforementioned N,N-dialkyl substituted aminoethanethiols and their salts, excluding compounds like O,O-Diethyl S-[2-(diethylamino)- ethyl] phosphorothioate and Thiodiglycol (bis(2-hydroxyethyl) sulfide) covered under 2930.90.92.08, or Cysteine hydrochloride and 2-Ethylhexyl mercaptoacetate under 2930.90.92.10. It also differs from 2930.90.92.25, which pertains to organophosphorus compounds with specific alkyl group attachments.

As a leaf node within the HTS, this classification does not have further subdivisions. Therefore, classification within this code hinges on a precise match to the chemical structure described. Importers and exporters should carefully verify the chemical identity of the aminoethanethiols and their salts to ensure correct classification under 2930.90.92.22, confirming they are not among the explicitly excluded dimethylamino or diethylamino derivatives.