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stereonotations [2012/10/13 14:46] sanmarkstereonotations [2012/10/14 09:43] sanmark
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 The mcule registration system supports the distinction between unknown and unspecified/undefined cis-trans configurations. Unknown cis-trans configuration represents a structure having either E or Z configuration but definitely one of them. In unspecified/undefined cases the structure can also represent the mixture of the cis and trans isomers. The mcule registration system supports the distinction between unknown and unspecified/undefined cis-trans configurations. Unknown cis-trans configuration represents a structure having either E or Z configuration but definitely one of them. In unspecified/undefined cases the structure can also represent the mixture of the cis and trans isomers.
  
-Although the mcule registration system can distinguish between unknown and unspecified/undefined cases, the currently implemented molecule editor and visualization tools (ChemWriter and ChemVector) don’t provide different bond types for these two configuration types. Unknown and unspecified/undefined cis-trans configurations are therefore both displayed by crossed double bond. If unspecified double bonds are present, we indicate them in the comment field of the compound index pages.+Although the mcule registration system can distinguish between unknown and unspecified/undefined cases, the currently implemented molecule editor and visualization tools (ChemWriter and ChemVector) don’t provide different bond types for these two configuration types. Unknown and unspecified/undefined cis-trans configurations are therefore both displayed by crossed double bond.
  
 ===Tetrahedral configuration=== ===Tetrahedral configuration===
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 | unknown                   | configuration type is uncertain: probably absolute but can be relative or racemic | | unknown                   | configuration type is uncertain: probably absolute but can be relative or racemic |
  
-Interpretation of the absolute, relative and racemic types is shown in figure. The unknown configuration type indicates that configuration type cannot be the determined surely. One should treat structures with unknown configurations as if they have absolute configuration not confirmed by the compound supplier.+Interpretation of the absolute, relative and racemic types is shown in table. The unknown configuration type indicates that configuration type cannot be the determined surely. One should treat structures with unknown configurations as if they have absolute configuration not confirmed by the compound supplier.
  
 Stereo configuration types are indicated by the displayed REL, RAC, or UNK stereo labels. If the structure has absolute stereo configuration type or does not contain any stereocenters, no stereo labels are displayed. In these cases the interpretation of the configuration is straightforward. Stereo configuration types are indicated by the displayed REL, RAC, or UNK stereo labels. If the structure has absolute stereo configuration type or does not contain any stereocenters, no stereo labels are displayed. In these cases the interpretation of the configuration is straightforward.
 +
 +{{ :stereonotations:stereo_labels.png |}}
stereonotations.txt · Last modified: 2012/10/15 12:27 by sanmark