2932.99.90 - Other

This category, HTS 2932.99.90, encompasses heterocyclic organic compounds that contain at least one oxygen heteroatom within their ring structure. It serves as a residual classification for such compounds not specifically enumerated in preceding subheadings within heading 2932, and that are not aromatic in nature. The "Other" designation signifies that these are compounds that do not fit into more specific classifications of oxygen-containing heterocycles.

Distinguishing this category from its sibling, "Aromatic," is crucial. While both fall under the umbrella of oxygen-containing heterocyclic compounds, this subheading specifically excludes those where the heterocyclic ring system possesses aromatic character. Aromaticity is determined by specific structural and electronic properties, typically involving delocalized pi electrons within a planar ring. Therefore, compounds classified here will lack these aromatic features.

The subcategories under HTS 2932.99.90 provide further refinement. 2932.99.90.10 specifically covers glucosamine and its salts and esters, which are important biologically active compounds. All other oxygen-containing heterocyclic compounds not meeting the criteria for glucosamine and its derivatives, and which are also non-aromatic, will be classified under the residual subheading 2932.99.90.90.