抄録
The metal chelating action of the S=0 part of sulfamyl part was assumed on the basis of studies of the electronic state of the sulfamyl part of thiazide diuretics because of its similarity to the phosp'nate part p of ATP. The diuretic activity and inhibitory effect of thiazide on carbonic anhydrase may be explained as resulting from Mg++ and Zn++ chelating. ROBLlN'S model explaining the inhibitory effect of the sulfamyl part on carbonic anhydrase activity did not seem adequate from the viewpoint of quantum-chemistry.