Validation Example 15

Entry C10783 in KEGG ((−)-Sparteine):

[Image]

has two ambiguously drawn stereocenters around the central bridge. While chemists would probably have no problem to interpret them correctly (i.e., as intended), the interpretation by chemical software1 depends on whether the angle between the plain (non-wedge) bonds is slightly more or slightly less than 180°2. This is an obvious cause for ambiguity. See elsewhere for a more elaborate explanation.

Entry MC009741 in BioMeta has now unambiguously drawn stereochemistry:

[Image]

References and Notes:

  1. Dalby A, Nourse JG, Hounshell WD, Gushurst AKI, Grier DL, Leland BA, Laufer J: Description of Several Chemical Structure File Formats Used by Computer Programs Developed at Molecular Design Limited.  J. Chem. Inf. Comput. Sci. 1992, 32: 244-255.
  2. This can be verified by using ISIS or other database software that interpret molfiles.