N-acetyl L-cysteine; CAS# 616-91-1; thiols; mercaptans; carboxylic acids; 867410 modified

HQ 950914 April 22, 1992 CLA-2 CO:R:C:F 950914 EAB CATEGORY: Classification TARIFF NO.: 2930.90.4520 Mr. Marvin Trief Arrow Chemical Inc. P.O. Box 580 Westwood, New Jersey 07675 Re: N-acetyl L-cysteine; CAS# 616-91-1; thiols; mercaptans; carboxylic acids; 867410 modified Dear Mr. Trief: This is a decision on a reconsideration of NYRL 867410 (October 29, 1991), in part which classified N-acetyl L-cysteine under subheading 2930.90.5050 of the Harmonized Tariff Schedule of the United States Annotated, then generally dutiable at 3.7% ad valorem. FACTS: The merchandise is N-acetyl L-cysteine, CAS Registry Number 616-91-1. It is also referred to as acetylcysteine and L-a- acetamido-b-mercaptopropionic acid. Generally speaking, simple organic compounds formed by the replacement of a hydrogen atom of hydrogen sulfide by an aliphatic, aromatic or heterocyclic radical are referred to as "thiols," e.g. methanethiol; whereas, polyfunctional compounds so formed are often described with the prefix "mercapto," such as mercaptoacetic acid. NYRL 867410, supra, classified the merchandise under subheading 2930.90.5050, HTSUSA, a basket provision for other organo-sulfur compounds, dutiable in 1991 at the column 1 general rate of duty of 3.7% ad valorem. ISSUE: What is the proper classification under the HTSUSA of N- acetyl L-cysteine, CAS Registry Number 616-91-1, also referred to as acetylcysteine and L-a-acetamido-b-mercaptopropionic acid? LAW AND ANALYSIS: Merchandise imported into the U.S. is classified under the HTSUSA. The tariff classification of merchandise under the HTSUSA is governed by the principles set forth in the General Rules of Interpretation (GRIs) and, in the absence of special language or context which otherwise requires, by the Additional U.S. Rules of Interpretation. The GRIs and the Additional U.S. Rules of Interpretation are part of the HTSUSA and are to be considered statutory provisions of law for all purposes. GRI 1 requires that classification be determined first according to the terms of the headings of the tariff schedule and any relative section or chapter notes and, unless otherwise required, according to the remaining GRI's taken in order. The terms of heading 2930, HTSUSA, accurately describe the subject merchandise as an organo-sulfur compound. Thereunder, subheading 2930.90.4520, describes mercaptocarboxylic acids. HOLDING: N-acetyl L-cysteine, CAS Registry Number 616-91-1, also referred to as acetylcysteine and L-a-acetamido-b- mercaptopropionic acid is classifiable under subheading 2930.90.4520, HTSUSA, a provision for organo-sulfur compounds; other; other; other; acids, mercaptocarboxylic acids. Entries of merchandise classified under this subheading are dutiable at the column one general rate of duty of 4.2% ad valorem. This decision should be considered a modification of NYRL 867410 pursuant to 19 CFR 177.9(d)(1). It is not to be applied retroactively to NYRL 867410 (19 CFR 177.9(d)(2)) and will not, therefore, affect past transactions for the importation of your merchandise under that ruling. For purposes of future transactions in merchandise of this type, NYRL 867410 will not be valid precedent. We recognize that pending transactions may be adversely affected by this modification, in that current contracts for importations arriving at a port subsequent to this decision will be classified pursuant to it. If such a situation arises, you may notify this office and apply for relief from the binding effects of this decision as may be warranted by the circumstances. Sincerely, John Durant, Director Commercial Rulings Division