Do one of the following to flip (mirror) a selected graphic from side to side:
Select the structure and click on the Flip Horizontal tool in the Chemistry toolbar.
Select the structure and choose Arrange > Flip Horizontal.
Select the structure, right-click anywhere in the drawing area to bring up the Drawing Area pop-up menu, and choose Arrange > Flip Horizontal from the menu.
If no graphic is selected, all of the objects in the drawing area flip together.