Chemical Data Processing Library C++ API - Version 1.1.1
Variables
CDPL::Chem::BondDirection Namespace Reference

Provides constants for the specification of directional bonds in Daylight SMILES and SMARTS strings. More...

Variables

const unsigned int NONE = 0x0
 Specifies that the bond has no associated direction. More...
 
const unsigned int UP = 0x1
 Specifies that the bond is directed upwards. More...
 
const unsigned int DOWN = 0x2
 Specifies that the bond is directed downwards. More...
 
const unsigned int UNSPECIFIED = 0x4
 In a substructure search query pattern this flag indicates that the specified query bond direction is not mandatory and that target bonds with an unspecified direction shall also be considered as a match. More...
 

Detailed Description

Provides constants for the specification of directional bonds in Daylight SMILES and SMARTS strings.

Directional bonds in Daylight SMILES or SMARTS strings are used to specify the configuration around a double bond by indicating the relative direction of the bonds to its substituent atoms. They have only a meaning when they occur on both sides of the double bond (see [SMILES, SMARTS]).

Variable Documentation

◆ NONE

const unsigned int CDPL::Chem::BondDirection::NONE = 0x0

Specifies that the bond has no associated direction.

◆ UP

const unsigned int CDPL::Chem::BondDirection::UP = 0x1

Specifies that the bond is directed upwards.

In SMILES and SMARTS strings up bonds are specified by a slash '/'.

◆ DOWN

const unsigned int CDPL::Chem::BondDirection::DOWN = 0x2

Specifies that the bond is directed downwards.

In SMILES and SMARTS strings down bonds are specified by a backslash '\'.

◆ UNSPECIFIED

const unsigned int CDPL::Chem::BondDirection::UNSPECIFIED = 0x4

In a substructure search query pattern this flag indicates that the specified query bond direction is not mandatory and that target bonds with an unspecified direction shall also be considered as a match.

The flag only has a meaning for directional bonds in SMARTS patterns where

  • its resulting bitwise OR combination with BondDirection::UP specifies that a matching target bond is required to have an upward or unspecified direction
  • and its combination with BondDirection::DOWN specifies that a target bond must have a downward or unspecified direction to be considered as a match.