Stereochemical Specification

R-7.2.2 Relative configuration

Chiral centres, of which the relative but not the absolute configuration is known, may be labelled arbitrarily as R* or S* (spoken R star, S star), preceded when necessary by appropriate locants. These prefixes are assigned by the sequence rule procedure, arbitrarily assuming that the centre of chirality first cited (which usually has the lowest locant) has the chirality descriptor R*. In complex cases, the stars may be omitted, and, instead, the whole name prefixed by rel- (for relative).

Examples to R-7.2.2

This HTML reproduction is as close as possible to the published version [see IUPAC, Commission on Nomenclature of Organic Chemistry. A Guide to IUPAC Nomenclature of Organic Compounds (Recommendations 1993), 1993, Blackwell Scientific publications, Copyright 1993 IUPAC]. If you need to cite these rules please quote this reference as their source.

Published with permission of the IUPAC by Advanced Chemistry Development, Inc.,, +1(416)368-3435 tel, +1(416)368-5596 fax. For comments or suggestions please contact