Bring the power of IUPAC naming to your desktop!

ACD/Name (Chemist Version) offers a standardized set of features for quick and simple generation of IUPAC names, and structures from names. It is a streamlined version of our popular ACD/Name software.

View a full description and pricing on our web store.

Characteristic (Functional) Groups

R-3.1 Unsaturation

As noted above (R-3.0), the treatment of unsaturation (of a saturated parent hydride) or saturation (of an unsaturated parent hydride) is different from that of other functions. This difference has implications for choice of parent hydride and for numbering. The following three subsections describe ways to indicate unsaturation/saturation.

See Also:
R-3.0 Introduction
R-3.2 Specification of Characteristic Groups
R-3.3 Functional Parent Compounds and Derived Substituent Groups
R-3.4 Functional Replacement

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