CLA-2 CO:R:C:F 950133 JGH

District Director of Customs
One Virginia Ave
Wilmington, North Carolina 28401

RE: Decision on Application for Further Review of Protest No. 1503-90-000037, on the Classification of Thymidine, under the Harmonized Tariff Schedule of the United States (HTSUS), a product of Germany.

Dear Sir:

This protest involves the classification of the chemical thymidine, entered in 1989-1990 by Burroughs-Wellcome Co.

FACTS:

Thymidine was originally entered under the provision for other gtLms, gum-resins in subheading 1301.90.90, HTSUS. Customs changed the classification to that for other heterocyclic compounds in subheading 2934.90.50, HTSUS. In a laboratory report it was described as a white, fluffy powder; an organic, heterocyclic compound having a chemical name of l-(2-Deoxy-B-DRibofuranosyl)-5- methyluracil.

Thymidine is described by the protestant as an intermediate chemical used in the production of zidovudine, an anti-HIV drug. It is claimed that it is derived from thymine, is a glycoside and that it is a constituent of DNA (deoxyribonucleic acid). It is further asserted that it is apparent by its chemical structure, that thymidine is a combination of a vegetable alkaloid (thymine) and a glycose (2-deoxyribose). In view of its structure, on the Protest it is contended that the thymidine is classifiable as a natural derivative of vegetable alkaloids, in subheading 2939.90.10, HTSUS, or as a derivative of glycoside in subheading 2938.90.00, HTSUS.

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ISSUE:

Whether thymidine is classifiable under the provision for other natural derivatives of vegetable alkaloids in subheading 2939.90.10, HTSUS, other glycosides, natural or reproduced by synthesis, in subheading 2938.90.00,HTSUS, or other heterocyclic compounds in subheading 2934.90.50, HTSUS.

LAW AND ANALYSIS:

The importer claims that since thymidine structurally appears to be a combination of a vegetable alkaloid (thymine) and a glycose (2-deoxyribose) it should be considered a derivative of the vegetable alkaloid thymine and, therefore, classifiable in subheading 2939.90.10, HTSUS. We note, however, that the importer states that the thymidine nucleoside is synthesized by the cleavage of DNA structures followed by a significant number of chemical synthesis steps. The finished nucleoside, though containing chemical structure which is found in alkaloids, consists of a significant amount of chemical synthesis steps. The finished nucleoside, though containing chemical structure which is found in alkaloids, consists of a significant amount of additional structure which would make the compound different than "a simple derivatized alkaloid." For this reason and the fact that thymidine is too far removed from a naturally occurring compound to be considered a natural derivative and, in addition, the chemical structure of thymidine is clearly not similar enough to the natural product from which it is obtained, we cannot consider the product to be a natural product from which it is obtained; nor can we consider it to be a natural derivative of a vegetable alkaloid.

To be classified as a derivative of a glycoside in heading 2938, the thymidine must be either naturally occurring or synthesized in a manner so that its chemical structure is identical to the structure of a naturally occurring glycoside. In the structure of thymidine, the original base and sugar are not joined by a glycosidic linkage through an oxygen atom as are all glycosides. As mentioned, thymidine is considered a nucleoside, or more specifically a n-glycoside or a glycoside having a nitrogen atom glycosidial bond. In addition technical literature supplied establishes that thymidine is found in its free, unbound form in different types of plants and animal organisms. Since the Explanatory Note (9) to heading 2938 lists "sinigrin", an s-glycoside having a sulfur atom glycosidal bond, as a glycoside classifiable in heading 2938, it is concluded that the intent of the heading is to include an n-glycoside like thymidine.

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HOLDING:

Thymidine is classifiable as a derivative of glycoside in subheading 2938.90.00, HTSUS.

You are directed to allow the protest in full.

A copy of this decision should be furnished the protestant with the Form 19 Notice of Action.

Sincerely,


Director
Commercial Rulings Division