Abstract
5-Amino-4-cyano-2-ethoxycarbonylaminothiazole (2), 2-ethoxycarbonylaminothiazolo[5,4-d]pyrimidine-7(6H)-one (4), and 5-ethoxymethyleneamino-4-cyano-2-ethoxycarbonylaminothiazole-4-carboxamide (9) were synthesized from 5-amino-2-ethoxycarbonylaminothiazole-4-carboxamide (1). Unlike simple 5-aminothiazoles, 1 and 2 did not undergo rearrangement in hot aqueous alkali, because of the role of their 2-ethoxycarbonylamino substituents. Thermogravimetric experiments on 1, 2, 4, and 9 revealed routine elimination of ethanol molecule from the NHCO 2C2H5 substituent of 1, 2, 4, and 9.
GRAPHICAL ABSTRACT
ACKNOWLEDGMENTS
We thank P. Ghosh for 1H NMR and 13C NMR spectral measurement. One of the authors (P. K. Ray) is thankful to the University Grants Commission, New Delhi, for a research fellowship.