BND Statistics BND terms classification unambiguous terms primary terms 3642 synonyms 9996 Markush rules 68 isomers (see right side) 5006 ambiguous terms local variant terms 208 term subsumptions 434 Markush terms 55 ambiguous terms 41 descriptive information abbreviations 71 Total 19471

Isomers Each of the these categories are unique in the sense they do not include the subsumed terms. Isomers break down as follows: Classification of isomers (definitions)   Classification of isomers (picture) structural isomers       skeletal isomers 1724   positional isomers 998   functional isomers 826   tautomers 51 stereoisomers       geometric isomers 663   enantiomers 446   diastereoisomers 66   meso-isomers 3   epimers 105   anomers 120   conformers 2   rotamers 2 Total   5006