From: Structure-based classification and ontology in chemistry
Abbrev. | Feature | Description | Examples of features | Examples of classes |
---|---|---|---|---|
IP.1 | Skeleton | The main carbon backbone of the molecule | A porphyrin skeleton | Porphyrins, pyridines |
IP.2 | Attached group | A functional group attached in some position on a skeleton | A methyl group on a pyridine skeleton | Methylpyridine |
IP.3 | Arbitrary part | A group or atom present in any position within the molecule | A carboxy group, an oxygen atom | Carboxylic acid, oxygen molecular entity |
IP.4 | Count of parts | The specific number, or a constraint on the number, of parts of a specified type | Three carboxy groups | Tricarboxylic acid |
IP.5 | Relative arrangement of parts | Relative arrangement of parts of a specified type | Relative arrangement of hydroxy group and amino group | Allothreonine, threonine |
CP.1 | Basic chemical properties such as charge | Presence of a specific number of charges, or unpaired electrons | Presence of a single positive charge | Anion, cation, dication |
TF.1 | Topological features - presence of cycles | Whether a molecule contains cycles of specified types | Presence of a cycle containing a hetero atom | Heterocyclic molecule |
TF.2 | Topological features - count of cycles | Presence of the specified number of distinct (smallest) cycles | Presence of two cycles | Bicyclic molecule, tricyclic molecule |
TF.3 | Topological features - interrelation between cycles (fusing, arrangements) | Relative arrangements and fusing between cycles | Presence of two cycles sharing one bond | Ortho-fused molecule |
TF.4 | Topological features | Overall aspects of connectivity, such as ring arrangements | Arrangement of rings into a cage shape | Polycyclic cage, fullerene, nanotube |
MC.1 | Mechanical connectivity | Mechanical connectivity/interlocking | Molecule with interlinked rotating parts | Rotaxanes, catenanes |
MC.2 | Mechanical shape of molecule | Features of overall shape of molecule | Knot-shaped molecule | Molecular Möbius strips, molecular knots |
SF.1 | Structural formula - atomic | A schema for structural formulae in terms of the overall atomic constitution | Molecule with formula C n H2n | Hydrocarbons, alkanes |
SF.2 | Structural formula - repeating substructural units (polymers) | Structural formulae in terms of relative numbers of substructural units | Macromolecule with repeated ethylene units | poly(ethylene), poly(propylene) |