| Introduction |
This section identifies techniques for controlling ring formation in substructure search results. |
| Definition |
Substructure searching retrieves matches where rings or chains of a structural skeleton are embedded within a larger ring system. |
| Default retrieval possibilities for rings |
By default, a substructure search on  retrieves the following:
|
Structure matches |
Example |
| Exactly as you drew it |
|
| Substituted at open positions |
|
| With the ring side-fused to another ring |
|
| With the ring spiro-connected to another ring |
| |
| Default retrieval possibilities for chains |
By default, a substructure search on  retrieves the following:
|
Structure matches |
Example |
| Exactly as you drew it (with assumed hydrogens) |
|
| Substituted at open positions |
|
| With the chain bonds forming rings |
|
| With the chain atoms part of a spiro ring |
| |
| Controlling ring formation |
The Lock Out Rings tool  controls ring formation.
|
If the Lock Out Rings tool is applied to a |
Structure matches with the following attributes are NOT retrieved |
| Ring system |
Side- or spiro-fused rings on the ring system |
| Chain |
Rings formed from bonds in the chain | |
| Note |
The Lock Out Rings tool does not prevent substitution at open positions.
Tools and structure drawing techniques are available to control substitution. |
Updated 4/15/2009 10:34:06 AM
