Toward Tissue-Selective Pancreatic B-Cells K<sub>ATP</sub> Channel Openers Belonging to 3-Alkylamino-7-halo-4<i>H</i>-1,2,4-benzothiadiazine 1,1-Dioxides
作者:Pascal de Tullio、Bénédicte Becker、Stéphane Boverie、Michael Dabrowski、Philip Wahl、Marie-Hélène Antoine、Fabian Somers、Sophie Sebille、Raogo Ouedraogo、John Bondo Hansen、Philippe Lebrun、Bernard Pirotte
DOI:10.1021/jm021117w
日期:2003.7.1
3-(Alkylamino)-7-halo-4H-1,2,4-benzothiadiazine 1,1-dioxides were synthesized, and their activity on rat-insulin-secreting cells and rat aorta rings was compared to that of the K-ATP channel activators diazoxide and pinacidil. Structure-activity relationships indicated that an improved potency and selectivity for the pancreatic tissue was obtained by introducing a fluorine atom in the 7-position and a short linear (preferably ethyl) or cyclic (preferably cyclobutyl) hydrocarbon chain on the nitrogen atom in the 3-position. By contrast, strong myorelaxant activity was gained by the introduction of a halogen atom different from the fluorine atom in the 7-position and a bulky branched alkylamino chain in the 3-position. Thus, 3-(ethylamino)-7-fluoro-4H-1,2,4-benzothiadiazine 1,1-dioxide (11) expressed a marked inhibitory activity on pancreatic B-cells (IC50 = 1 muM) associated with a weak vasorelaxant effect (ED50 > 300 muM), whereas 7-chloro-3-(1,1-dimethylpropyl)amino-4H-1,2,4-benzothiadiazine 1,1-dioxide (27), which was only slightly active on insulin-secreting cells (IC50 > 10 muM), was found to be very potent on vascular smooth muscle cells (ED50 = 0.29 muM). Radioisotopic and electrophysiological. investigations performed with 7-chlorinated, 7-iodinated, and 7-fluorinated 3-alkylamino-4H-1,2,4-benzothiadiazine 1,1-dioxides confirmed that the drugs activated K-ATP channels. The present data revealed that subtle structural modifications of 3-(alkylamino)-7-halo-4H-1,2,4-benzothiadiazine 1,1-dioxides can generate original compounds activating K-ATP channels and exhibiting different in vitro tissue selectivity profiles.