Flip a molecule

You might need to flip the whole or parts of the structures.

These operations are located in the Edit > Transform menu.

If no selection is made, the operation will be executed on the whole structure (except for Group Flip).

The flip operation is equal to a rotation of 180° around a horizontal or vertical axis in the plane of the drawing.
All flips result in stereocenter retention.

Horizontal flip
(around y axis)


Vertical flip
(around x axis)


Rotate 180°
(in canvas plane, around z axis)


Horizontal Flip, Vertical Flip, Rotate 180°

Flip a selection:

  1. Select part of the structure.

  2. Right-click on the structure or go to Edit > Transform menu.

  3. Click on the command.

Flip the whole structure without selection:

  1. Go to the Edit > Transform menu.

  2. Click on the command.

Note: If no structure is selected, the right-click on the canvas will not offer the flip command.

Group Flip

The Group Flip operation can be executed only on a selected structure connected to the rest of the molecule by only one bond (of any type): the selection can not be in the "middle" of a molecule. The selection is not permitted for disjunctive structures either.

This operation rotates the selected group by 180° around an axis set on the bond connecting the selection to the rest of the molecule. Stereocenters in the molecules are retained, the wedge bond styles change to keep the stereo information.

Group flip


  1. Select part of the molecule.

  2. Right-click on the canvas and select Transform > Group Flip; or go to the Edit > Transform menu.

  3. Select Flip > Group.