I. NOMENCLATURE AND FORMULA 325 



would be named to give the lowest possible number to the carbon atoms 

 bearing groups other than unsubstituted hydroxyl. 



The explicit rules for naming inositol derivatives are presented below 

 with amplifications in which emphasis is given to naming derivatives of the 

 vitamin ?n7/o-inositol. 



Rule 1 . In accordance with established practice in the carbohydrate field 

 the trivial names of the 'parent inositols will be used. 



This rule is self-explanatory from Table I and from what has been 

 said above concerning reasons for using the prefix myo rather than i or 

 mcso to designate the nutritionally important isomer. 



Rule 2. 7^ he structures of the optically active cyclitols and of all optically 

 active derivatives of the other cyclitols are designated as belonging to the d or l 

 series^ based upon the configuration of the highest numbered carbon atom. 



Some method is obviously needed to distinguish the name of a compound 

 from that of its enantiomorph. In the field of carbohydrate chemistry it 

 has been the general practice to designate the configuration of a sugar 

 molecule according to the configuration of its highest numbered asymmetric 

 carbon atom. The configuration of this carbon atom is established by 

 relating it to the configurations of the recognized standard compounds, d- 

 and L-glyceraldehyde. This practice may be extended to the inositols by 

 projecting the highest numbered carbon atom (i.e., number 6) onto a plane 

 with carbon atoms 1 and 5 projecting below the plane (away from the viewer) 

 and the H and OH above the plane (toward the viewer). 



5 C 5 C 



This rule would be applied to naming two enantiomorphic monophos- 

 phoric esters of 7/?//o-inositol, X and XI, in the following manner. 



OPO3-7 



By comparison with Table I it is apparent that both are m?/o-inositol-l- 

 phosphates. Their configurations are determined by projecting carbon 

 atom 6 onto a plane, as described above. Hudson's'" projection formulas 



*" C. S. Hudson, Advances in Carbohydrate Cheni. 3, 1 (1948). 



