186 



Essays in Biochemistry 



in the chair form reveals that the carbon atoms are equidistant from 

 a plane passing through the center of the molecule. Six of the free 



Fig. 2. The cyclohexane ring in the chair form. Equatorial bonds are shown as 



lines, north polar bonds as lines ending in solid circles, and south polar bonds by 



lines ending in open circles. 



n 



in 



3D 



VII 



VIII 



Fig. 3. The conformations of the inositols. Equatorial hydroxyl groups are 



represented by lines, north polar hydroxyl groups by solid circles, and south polar 



hydroxyl groups by open circles. The hydrogen atoms are not shown. 



bonds on the carbon atoms are located in that plane projecting out- 

 wards and are called equatorial bonds. The other six bonds are per- 

 pendicular to the plane being directed alternately upwards (north 



