Validation Example 13

Entry C02079 in KEGG (Staurosporine):

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has "reversed" wedged bonds between the ether carbon atoms and the attached nitrogen atoms, triggering the complaint "invalid sp3 stereocenter" from the validation program. Of course, the ether carbons are stereocenters and the bonds simply point the wrong way. Reference 1 (found using a Google Scholar search on "staurosporine stereochemistry") yields unambiguously the absolute stereochemistry (and rotation) of staurosporine. The KEGG structure seems to indicate the enantiomer(!) of the natural product.

Entry MC001873 in BioMeta, now provided with the correct stereochemistry, is duly called (+)-staurosporine:

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Reference:

  1. Wood JL, Stoltz BM, Goodman SN, Onwueme K: Design and Implementation of an Efficient Synthetic Approach to Pyranosylated Indolocarbazoles: Total Synthesis of (+)-RK286c, (+)-MLR-52, (+)-Staurosporine, and (−)-TAN-1030a.J. Am. Chem. Soc. 1997, 119: 9652-9661.