Characterization of the hydrochlorothiazide: β-Cyclodextrin inclusion complex. Experimental and theoretical methods

RENÉE ONNAINTY; ESTEBAN SCHENFELD; MARIO QUEVEDO; MARIANA A. FERNÁNDEZ; MARCELA LONGHI; GLADYS GRANERO

AMER CHEMICAL SOC

Lugar: Washington; Año: 2013 vol. 117 p. 206 - 206

ydrochlorothiazide (HCT) is one of the mostcommonly prescribed antihypertensive drugs. In an attempt togain an insight into the physicochemical and molecular aspectscontrolling the complex architecture of native beta-cyclodextrin(beta-CD) with HCT, we performed multiple-temperature−pHisothermal titration calorimetric measurements of the HCT:beta-CD system, together with proton nuclear magnetic resonancespectroscopy (1H NMR), phase solubility analysis, and molecularmodeling methods. The AL-type diagrams, obtained at differentpH values and temperatures, suggested the formation ofsoluble 1:1 inclusion complexes of beta-CD with HCT. The correspondingstability constants (K1:1) were determined by phasesolubility studies and compared with those obtained by ITC,with good agreement between these two techniques being found. The three-dimensional array of the complex was studied by 1HNMR and molecular modeling methods.