9902.03.33 - (2Z,4E)-5-[(1S)-1-Hydroxy-2,6,6-trimethyl-4-oxo-2-cy- clohexen-1-yl]-3-methyl-2,4-pentadienoic acid ((+)-Abscisic acid) (CAS No. 21293-29-8) (provided for in subheading 2918.99.50)

This HTS category, 9902.03.33, specifically classifies (2Z,4E)-5-[(1S)-1-Hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexen-1-yl]-3-methyl-2,4-pentadienoic acid, more commonly known as (+)-Abscisic acid. This compound is a naturally occurring plant hormone that plays a crucial role in various growth and developmental processes, including seed dormancy, leaf abscission, and stress responses. Its CAS Number, 21293-29-8, serves as a unique identifier for this specific chemical substance.

While the broader HTS system contains numerous entries for chemicals and organic compounds, this particular subheading is reserved for Abscisic acid when imported under specific temporary legislation or special classification provisions, as indicated by its Chapter 99 placement. It is important to note that this specific classification is provided for in subheading 2918.99.50, suggesting that under normal circumstances, Abscisic acid would be classified within Chapter 29, which covers organic chemicals. The presence in Chapter 99 signifies a temporary or specialized treatment for this substance, often related to agricultural policy or trade agreements.

As a leaf node, this category does not have further subcategories. Its purpose is to provide a distinct classification for (+)-Abscisic acid under specific regulatory or temporary measures, differentiating it from other organic acids or plant hormones that might fall under different, more general tariff lines. Classification within this subheading would be contingent on meeting the specific conditions and requirements outlined by the governing temporary legislation.