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Structure Preferences: Chemistry


What it does...

Show VPA

Shows the variable substituent's connections to its ring nodes in a Variable Point of Attachment (VPA) as dotted bonds. These can subsequently be hidden by deselecting Show VPA.


Sets the default for Markush attributes. This may be changed for any given atom with the Markush Attributes or the Element selection from the QueryDef menu.

Use Bond Algorithm

This default is used when drawing queries for searching. All bonds are set to exact/normalized if this option is unchecked; otherwise, the bond algorithms are applied.

Show Reactions

When this option is checked, reaction information is displayed, and reaction drawing tools on the drawing palette are activated. This option is available via the RXN button on the toolbar.

Markush Match Level Defaults

Markush Attributes affect search results only in the MARPAT database. The defaults for Ring Nodes or Chain Nodes can be changed.

Methyl Display

Display CH3 or Me.


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