Isoxazoles VIII. Preformulation Studies of an Isoxazolyl-naphthoquinone Derivative

LONGHI MARCELA, BERTORELLO MARÍA, AND GRANERO GLADYS.

JOURNAL OF PHARMACEUTICAL SCIENCES

John Willey & Sons

Lugar: New York, USA; Año: 1994 vol. 83 p. 336 - 338

0022-3549

The degradation kinetics of 2-hydroxy-N-(3,4-dimethyl-5-isoxazolyl)-1,4-naphthoquinone-4-imine (1) in a 25 % solution of ethyl alcohol and water has been studied. The rate constant were observed to follow pseudo-first-order kinetics in all cases. The pH-rate profile indicated a negligible decomposition at pH values higher than its pKa2 values (5.40 ± 0.14 (n = 6)). Un-ionized 1 was subject to specific acid catalysis. The ionic strength did not affect the stability of the drug. These data can be used to develop a stable oral liquid dosage form of the drug.