ESTER FUNCTIONAL GROUP FULL

Examples:ģ-Oxoandrost-4-en-17 -yl acetate (trivial name testosterone acetate)ġ7 -Hydroxy-20-oxopregn-5-en-3 -yl sulfate When necessary locants should be used with the anionic part of the name. and inserting this before the locant with a Greek letter to designate position and configuration. The steroid name is formed by replacing the terminal -e of the hydrocarbon name by -yl, -diyl, etc. The -olide ending of these names denotes the lactone grouping, and substituents must be named as prefixes.Įsters of steroid alcohols are named by the appropriate steroid substituent group followed by that of the acyloxy group in its anionic form. Similarly, if example 54 was called 7 -acetylthio-3-oxo-21 -homo-17-pregn-4-eno-21 ,17-lactone (name not recommended), then the lactone carbonyl would be C-21a (see 3S-6.1 for use of homo). If example 53 was called 3 -hydroxy-23,24-dinorchol-5-eno-21,18-lactone (name not recommended), then the lactone carbonyl would be C-21 (see 3S-6.2 for use of nor). Note In examples 53 and 54 the suffix carbolactone corresponds to a substituent with an additional carbon atom which is numbered accordingly (see 3S-2.7 ). The lactonised hydroxyl group is not stated separately. (a) Lactones, other than cardanolides and bufanolides, are named by changing the ending -ic acid or -carboxylic acid of the name of the hydroxy acid to -lactone or -carbolactone respectively, preceded by the locant of the acid group and then the locant of the hydroxyl group. (d) Esters are conveniently named in a similar way. (c) Names of salts are formed by stating the cation and using, as a separate word, the ionic form of the name of the acid. This name, etianic acid, is now abandoned. Note Compound 48 was formerly called 5 ,17a(H)-etianic acid. Note that in this case the acid contains one more carbon atom than the parent compound. C-COOH, >CH-COOH or -CH 2-COOH the suffix is -carboxylic acid or, in the ion form, -carboxylate. (b) If an acid is formed by substitution of a hydrogen atom in CH, >CH 2 or -CH 3 by a carboxyl group, i.e. In biochemical papers, these compounds are often named as anions, the counter-ion being unspecified in this case, the suffix is -oate. (a) If a methyl group is changed into a carboxyl group, the suffix is -oic acid it is preceded by the appropriate locant. the methyl groups are indicated by a bond without lettering, and the hydrogen atoms at C-8, C-9 and C-14 are omitted.Īcids, their salts and esters are generally named by use of suffixes. In this section, the formulae of examples correspond to 2b, i.e.

The following recommendations are on these principles. being elided before a vowel (presence or absence of numerals has no effect on such elisions).

Suffixes are added to the name of the saturated or unsaturated parent system (see 3S-2.5), the terminal e of -ane, -ene, -yne, -adiene etc. The choice for suffix is made according to an order of preference that is laid down in the most important part of this order, for steroids, is as follows in decreasing preferences: onium salt, acid, lactone, ester, aldehyde, ketone, alcohol, amine. When more than one type is present that could be designated as suffix only one type may be so expressed and the other types must be designated as prefixes. When possible, one type of substituent must be designated as suffix. Lists of these two types are given in Tables I and II respectively section C-10 of. Most substituents can be designated either as suffixes or prefixes some, however, the commonest being halogens, alkyl groups (see 3S-2.7 and 3S-2.8) and alkoxy groups, can only be designated as prefixes.

ESTER FUNCTIONAL GROUP FULL

For full details, the reader is referred to the IUPAC Recommendations. Therefore, and for the benefit of the biochemist not so familiar with the recommendations of substitutive nomenclature, these are outlined and exemplified here. However, there are some special problems in the application of these recommendations to natural products like steroids. Their nomenclature follows the general recommendations of the nomenclature of organic compounds (Sections C and D in ). Table 1) carrying various functional groups.

Nearly all biologically important steroids are derivatives of the parent hydrocarbons (cf. Steroids with heterocyclic rings in the side chainĤ.3 Esters of sterols and steroid alcohols References for this section 3S-4.0 to 3S-4.3 The Nomenclature of SteroidsĬontinued from 3S-3.

Ester functional group