The systematic nomenclature of simple substituted heterocycles

Numerotation of the ring

The numbering is done according to the order of priority of the heteroatoms:

O S -N< -N=

Examples:

1,3-Oxazepine

1,2,4-Triazole

Substituents

As with the           functions of aliphatic compounds , the priority function is written in suffix, the others as well as the alkyl groups and halogens, in prefix. Are considered absolutely priority: -CHO carbaldehyde -CN carbonitrile -COOR alkyl carboxylate -COOH carboxylic acid and the like.

Examples:

Pyridine-2-carbaldehyde

Thiophen-3-ol

4-Fluoro-5-methyl-1,3-thiazole-2-carbamide

The ring as a substitent

If the ring is attached to an alkyl chain of several C atoms and carrying a priority function, then it is considered as a substituent:

Example:

2-(2-Isopropyl-5-methylpyridin-4-yl)ethanol