Intramolecular Rearrangement of α-Amino Acid Amide Derivatives of 2-Aminobenzothiazoles.
Tetrahedron Lett
; 55(30): 4193-4195, 2014 Jul 23.
Article
in En
| MEDLINE
| ID: mdl-25018567
ABSTRACT
We have found that α-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 α-amino acid amide derivatives of 2-aminobenzothiazoles. However, a related reaction involving 2-semicarbazido benzothiazoles has been recently reported.
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Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Tetrahedron Lett
Year:
2014
Document type:
Article