Y. Maki, T. Hiramitsu, M. Suzuki
Jun 25, 1974
Citations
0
Influential Citations
14
Citations
Journal
Chemical & Pharmaceutical Bulletin
Abstract
The reaction of 1, 3-dimethyl-5-nitro-6-chlorouracil with 2-aminothiophenol in benzene containing an excess of triethylamine gave 1, 3-dimethyl-10H-pyrimido (5, 4-b) (1, 4) benzothiazine-2, 4 (1H, 3H) dione quantitatively via the Smiles rearrangement. The reaction in acetic acid, however, resulted in the formation of 2-methyl-4-nitropyrimido (4, 3-b) benzothiazoline-1, 3 (2H, 10H)-dione in 78% yield, involving an unusual uracil-ring cleavage which appears to occur in a benzothiazoline intermediate in the course of the acid-catalized Smiles rearrangement.