User guide

Reaction center
The Reaction Center property specifies how the selected bonds are affected in a reaction. This property is meaningful
only when searching a database containing chemical reactions.
Unspecified. Default. Finds compounds regardless of whether the selected bonds are affected by the reaction.
Center. Finds compounds where the selected bonds are affected by a reaction, but the type of change is unspecified.
Make/Break. Finds compounds where the selected bonds are either broken or created in a reaction.
Change. Finds compounds where the bond order of the selected bonds changes in a reaction.
Make & Change. Finds compounds where the selected bonds are formed, broken, or undergo a change in bond
order.
Not Center. Finds compounds where the selected bonds are not part of the reaction center.
Not Modified. Finds compounds where the selected bond’s orders do not change, but which may or may not be part
of the reaction center.
Unmapped. Finds all compounds.
Element lists
An element list is a list of atoms that are allowed at a specified location. For example, the query structure below
allows bromobenzene, Iodobenzene, or chlorobenzene to be returned. An example of an element list is:
Figure 11.4: An element list as an atom label
The elements in the list must be separated by commas. A space after each comma and brackets are optional.
Note: An element list may contain only atomic symbols, plus D (deuterium) and T (tritium).
To create an element list:
1. Open an atom label text box.
2. Type an open bracket (“[“) followed by a list of elements separated by commas (“Cl, Br, I”), followed by a close
bracket (“]”).
3. Close the text box.
The figure below shows a query structure created to find compounds matching the following criteria:
ChemBioDraw 13.0
Chapter 11: Query structures 211 of 401