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How to list every stereoisomer of a structure

Select the structure and choose Object › Chemistry › Stereoisomers. Every stereoisomer is listed with its own R/S and E/Z, meso forms counted once; press Place on one or Place all.

Steps

  1. Draw or insert the structure, for example tartaric acid, and select it.

  2. Choose Main menu › Object › Chemistry › Stereoisomers.

  3. The window says how many stereocenters there are and lists each stereoisomer, with the R/S and E/Z of every center written on its drawing and summed up under it. A meso form is counted once and marked Meso; enantiomers say which number they mirror.

    Tartaric acid's 3 stereoisomers: the meso form (S, R) and the enantiomers R, R and S, S.Tartaric acid's 3 stereoisomers: the meso form (S, R) and the enantiomers R, R and S, S.

  4. Press Place under one to put it on the page, or Place all for every one.

Atoms, bonds and ringsHow to show R and S, E and Z labelsTurn on View › Show stereochemistry. Each stereocenter gets R or S and each stereo double bond E or Z, worked out from the CIP priority rules and updated as you draw.Atoms, bonds and ringsHow to choose undefined stereocentersSelect the structure and choose Object › Chemistry › Choose undefined stereocenters. Athanor proposes wedges; Accept keeps them, Reject proposes hashes, and rejecting again leaves them undefined.Atoms, bonds and ringsHow to mark stereo groups (AND, OR, absolute)Select the drawn stereocenters and choose Object › Stereo group: absolute, Stereo group: new AND (racemic) or Stereo group: new OR (one of two, unknown which). Stereo group: clear removes the mark.

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Last updated Nov 12, 2026