2 propylpentyl sulfamate 5 amino 1,3,4 thiadiazole 2 sulfonamide 5 tert butoxycarbonylamido 1,3,4 thiadiazole 2 sulfonamide Anti-convulsant activity Pharmacophoric pattern Sodium channel Sulfamoyl derivatives acetazolamide anticonvulsant activity anticonvulsive agent calculation carbamazepine carbonate dehydratase conference paper drug conformation drug mechanism drug structure drug synthesis electric shock enzyme inhibition n butyl 2 propylpentyl sulfamate n cyclopropyl 2,3 isopropylidene 4,5 sulfonyl beta dextro fructopyranose sulfamate n methyl 2,3 isopropylidene 4,5 sulfonyl beta dextro fructopyranose sulfamate n morpholine 2 propylpentyl sulfamate pharmacophore phenytoin quantum chemistry rwj 37947 structure analysis sulfonamide