|CDX Constant Name:||kCDXObj_NamedAlternativeGroup|
|CDX Constant Value:||0x800A|
|Contained by objects:||kCDXObj_Page, kCDXObj_Group|
|First written/read in:||ChemDraw 4.0|
A NamedAlternativeGroup is a container object holding fragments that represent alternative substituents for a query. It should contain two or more fragments and/or groups containing fragments. The optional property kCDXProp_NamedAlternativeGroup_Valence (1 if not present) describes the number of external connection points. Each fragment or group must contain exactly that number of external connection point nodes. Generally, there will be a Node in another fragment not contained in this NamedAlternativeGroup which has Node_Type equal to kCDXNodeType_NamedAlternativeGroup, and a kCDXProp_Node_AltGroupID property that refers to this NamedAlternativeGroup object.
The number of bonds connected to a named alternative group node should match the valence (number of external connection points in each fragment) of the alternative group. If a named alternative group node has more than one bond connected to it, the named alternative group node should contain a kCDXProp_BondOrdering property.
A NamedAlternativeGroup is also commonly known as an R-Group or a G-Group.
A NamedAlternativeGroup must contain a Text object, and a NamedAlternativeGroup without any contained fragments is pretty useless. It has no required properties.
|A logical collection of objects.|
|A collection of nodes and their connectivity (bonds).|
|An arbitrary block of (possibly styled) text.|
|Arbitrarily named property, one or more of which can be attached to any ChemDraw object.|
|A unique identifier for an object, used when other objects refer to it.|
|Back-to-front ordering index in 2D drawing.|
|Signifies whether chemical warnings should be suppressed on this object.|
|A warning concerning possible chemical problems with this object.|
|The object is visible if non-zero.|
|The smallest rectangle that encloses the graphical representation of the object.|
|The foreground color of an object represented as the two-based index into the object's color table.|
|The background color of an object represented as the two-based index into the object's color table.|
|The bounding box of upper portion of the Named Alternative Group, containing the name of the group.|
|The bounding box of the lower portion of the Named Alternative Group, containing the definition of the group.|
|The number of attachment points in each alternative in a named alternative group.|