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.


R-0.1.6 Italicization

Italicizing mainly serves to mark letters which are not involved in the primary stage of alphabetical ordering. In manuscripts, italics are conventionally indicated by underlining.

R- Lower case italic letters are used in descriptors of fusion sites in names of fused ring systems.

Example to R-

Thieno[3,2-b]furan (R-

The lower case italic letters o, m, p, may be used in place of the numerical locants 1,2(ortho), 1,3(metha), and 1,4(para), respectively, for disubstituted benzene derivatives, but the numerals are preferred.

Examples to R-

o-Dinitrobenzene (R-5.3.2)

p-Aminobenzoic acid (R-5.4.1)

R- Italicized element symbols, such as O-, N-, P-, S-, are locants indicating attachment to these heteroatoms.

Examples to R-

N-Methylbenzamide (R-

O-Ethyl hexanethioate (R-

The italic element symbol H denotes indicate or added hydrogen.

Examples to R-

3H-Pyrrole (R-1.3)

Phosphinin-2(1H)-one (R-1.3)

R- Italic words, syllables and capital roman letters are used in some structural descriptors and in stereodescriptors.

Examples to R-

sec (R-,

tert (R-5.3.1) (but not "iso" or "cyclo"),

cis, trans (R-7.1.1),

r, c, t, (R-7.1.1)

R, S (R-7.2.1); R* (spoken R-star), S* (spoken S-star),

rel (R-7.2.2),

Z, E (R-7.1.2)

abeo (R-,

retro (R-, (but not "homo", "nor" or "seco")

R-0.1.7 Elision and addition of vowels
R-0.1.8 Order of prefixes

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