Solubility profiles of some isoxazolyl–naphthoquinone derivatives

Water, ethanol and n-hexane solubility and pH–solubility behavior of a homologous series of isoxazolyl–naphthoquinone derivatives, which exhibit important biological activity, were studied. Their p K a values were determined spectrophotometrically as well as from their pH–solubility profiles. Also, the molar aqueous solubility of these compounds was estimated with the equations developed by Yalkowsky and Valvani using the data of their melting points and octanol/water partition coefficients.