Biopharmaceutical studies on hydantoin derivatives. III. Physico-chemical properties, dissolution behavior, and bioavailability of the molecular compound of 1-benzenesulfonyl-5,5-diphenylhydantoin and antipyrine.

Physico-chemical properties, dissolution profiles, and bioavailability of the molecular compound composed of equimolar amount of 1-benzenesulfonyl-5, 5-diphenylhydantoin (BSDH) and antipyrine were studied. The spectral and thermal analyses suggest that the intermolecular force in the molecular compound is attributed to the hydrogen bond between 3-NH of BSDH and 5-C = 0 of antipyrine. In the aqueous media, the molecular compound decomposed to the constituents and there was no interaction between them. The dissolution behavior of BSDH from the molecular compound was characteristic, the high supersaturation being present for a long time, while the dissolution of antipyrine from the molecular compound was slow and continued for a long time. The dissolution profile of the molecular compound was truly reflected on the bioavailability in dogs. With respect to BSDH, the rate and the extent of bioavailability of the molecular compound were excellent. On the other hand, the absorption of antipyrine from the molecular compound was sustained for a long time. BSDH and antipyrine had no influence one another on the intrinsic rate constant of transport through the intestinal membrane and on the pharmacokinetic constants such as the volume of distribution and the elimination rate constant.