2918.29.39.00 - 4,4-Bis(4-hydroxyphenyl) pentanoic acid; and 3,5,6-Trichlorosalicylic acid

This HTS category, HTS Code 2918.29.39.00, encompasses specific carboxylic acids that possess both a phenolic hydroxyl group and another oxygen-containing functional group, with the exclusion of simple phenol functionalities. The primary products classified here are 4,4-Bis(4-hydroxyphenyl) pentanoic acid, characterized by its complex bisphenol structure and pentanoic acid chain, and 3,5,6-Trichlorosalicylic acid, a halogenated derivative of salicylic acid. These compounds are distinct due to their precise chemical structures, which differentiate them from other entries within the broader category of carboxylic acids with a phenol function.

When distinguishing this category from its siblings, it is crucial to note the specific chemical configurations. For instance, sibling categories may include simpler hydroxybenzoic acids, naphthoic acids, or compounds like 1,6-Hexanediol bis(3,5-dibutyl-4-hydroxyphenyl)propionate, which feature different arrangements of hydroxyl groups or additional functional groups that alter their classification. The defining characteristic of HTS 2918.29.39.00 lies in the specific combination of a pentanoic acid moiety with bisphenol functionality in one compound, and the trichlorinated salicylic acid in the other, setting them apart from less complex or differently substituted related compounds.

As this classification represents a leaf node in the HTS, there are no further subdivisions. Therefore, accurate classification within this code relies on precise identification of the chemical substances against the provided descriptions, ensuring that the goods imported or exported precisely match the chemical structures of 4,4-Bis(4-hydroxyphenyl) pentanoic acid or 3,5,6-Trichlorosalicylic acid. The absence of subcategories emphasizes the specificity of this designation for these particular organic chemical compounds.