Stereochemistry Representation and Manipulation

Rohde B. Stereochemistry representation and manipulation. In Schleyer PvR, Allinger NL, Clark T, Gasteiger J, Kollman PA, Schaefer HF, Schreiner PR, eds. The Encyclopedia of Computational Chemistry. Chichester John Wiley Sons, 1998 2726-2737. 

Stereochemical representation has been an integral part of the CAS Chemical Registry System since its inception in 1965 (see Stereochemistry Representation and Manipulation). Stereoisomers are considered to be different, individual substances, and each is assigned its own CAS Registry Number. The unique identification of stereoisomers permits the storage and retrieval of information collected from scientific literature about a specific isomer. About one-fourth of the over 17 million substances in the Registry File contain stereo information. 

Stereochemistry Representation and Manipulation Structural Similarity Measures for Database Searching Structure and Substructure Searching Structure Databases Structure Representation Three-dimensional Structure Generation Automation Three-dimensional Structure Searching Topological Indices Topological Methods in Chemical Structure and Bonding. 

Circular Dichroism Vibrational Configuration Interaction Configuration Interaction PCI-X and Applications Density Functional Theory (DFT), Hartree-Fock (HF), and the Self-consistent Field Magnetic Circular Dichroism of n Systems Molecular Magnetic Properties Nucleic Acid Conformation and Flexibility Modeling Using Molecular Mechanics Spectroscopy Computational Methods Stereochemistry Representation and Manipulation. 

The arrangement of atoms in three-dimensional space changes both structure and reactivity and is described in several different ways in chemical substance nomenclature (see Stereochemistry Representation and Manipulation). The most common stereochemical descriptions arise from multiple bonds and from asymmetric carbon atoms. Often, as in CAS systematic nomenclature, these stereochemical descriptions are handled as separate character strings not directly part of the chemical substance name. 

Chemical Abstracts Service Information System Nomenclature Automatic Generation and Conversion Online Databases in Chemistry Polymers Structural Representation Stereochemistry Representation and Manipulation. 

Stereochemical designations (see Stereochemistry Representation and Manipulation) can either be absolute or relative in either the query or target structures. Chiral (absolute stereochemistry) queries should only match absolute stereochemical targets, whereas relative stereochemical queries can match both absolute and relative target molecules. 

Networks in Chemistry NMR Chemical Shift Computation Ab Initio NMR Chemical Shift Computation Structural Applications NMR Data Correlation with Chemical Structure Quantitative Structure-Property Relationships (QSPR) Spectroscopic Databases Stereochemistry Representation and Manipulation Structure Generators Topological Methods in Chemical Structure and Bonding. 

A number of special features of chemical structures, and certain types of structure, cause special problems, particularly for computer representation. Stereochemistry is one of the most important of these (see Stereochemistry Representation and Manipulation). 

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