I Lab Services 

4.14.1 Structure Tab 

The first set of preferences to be decided upon is the Structure.  It specifies the preferred stereo 

conventions which will be used in name generation. 

Note 

In order for the stereochemistry of a chiral center of a sketched in molecule to be 

taken into account, the active centers must be designated with stereo bonds. 

4.14.1.1 Ignore Stereochemistry 

Specifies whether to ignore the configuration of carbon centers and carbon carbon double bonds 

or to take them into account and attribute corresponding stereodescriptors.  In the last case an 

asymmetric site will have its stereochemistry explicitly denoted in its name.  

For example: 

CH

3

H C

3

CH

3

H C

3

OH

Yes 

2 butene 2 butanol 

No 

2 butene, (2Z)  2 butanol, 

(2R)  

4.14.1.2  Stereo Wedge Direction 

This allows the user to choose between two possible procedures of stereo bond analysis.  

If Yes is selected, the  up  and  down  wedges which specify stereo centers will be analyzed with 

regard to their directions (depending on which atom a narrow end is attached).  

If No is selected, the sign ( up  or  down ) of the stereo wedge doesn't depend on the direction. 

For example: 

Cl

Cl

Cl

H C

3

H C

3

H C

3

CH

3

CH

3

CH

3

Yes 

butane, 2 chloro , (2R)  butane, 2 chloro , (2S)  butane, 2 chloro , (2R) 

No 

butane, 2 chloro , (2R)  butane, 2 chloro , (2R)  butane, 2 chloro , (2R) 

Note 

If  ignore  is selected, stereo bonds are not allowed between two chiral centers.  

For example: 

Br

OH

Cl

CH

3

Take into account  1 propanol, 3 bromo 3 chloro , (2R,3R)  

Ignore 

Refused to name 

ACD/I Lab via ChemSketch  

User's Guide 

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