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Intramolecular Rearrangement of ?-Amino Acid Amide Derivatives of 2-Aminobenzothiazoles.

ABSTRACT: We have found that ?-amino acid amide derivatives of 2-aminobenzothiazoles undergo a time-dependent, thermal rearrangement in which the amine group attacks the 2-position carbon of the thiazole ring to form a 5,5-spiro ring system. This is followed by sulfur leaving and air oxidation to the corresponding symmetrical disulfide. The isolated yields of such products are quite high (>70%) if there is conformational bias to further promote the intramolecular reaction such as for the 2-aminobenzothiazole amides derived from proline or 4-aminopiperidine-4-carboxylic acid. This rearrangement has not been described previously for ?-amino acid amide derivatives of 2-aminobenzothiazoles. However, a related reaction involving 2-semicarbazido benzothiazoles has been recently reported.

SUBMITTER: Pelletier JC

PROVIDER: S-EPMC4090782 | BioStudies | 2014-01-01

REPOSITORIES: biostudies

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