To this group belong creosote and its constituents. The most important of these phenol ethers are:

1. Anisol: Methylphenol ether, CH5OCH3.

2. Phenetol: Ethylphenol ether, C6H5OC2H5.

3. Guaiacol: Monomethyl ether of pyrocatechin, C6H4OH.OCH3.

4. Creosol: Methylguaiacol, C6H3CH3OCH3OH.

5. Creosote: A mixture of varying composition of 60-90 per cent. guaiacol, creosol, methylcreosol, C6H1.CH3,CH3,OCH3,OH, xylenol, C6H3CH3CH3OH, and phlorol, C6H4C2H5OH, and usually made of beechwood.

Creosotes of commerce from species of pine consist of much less guaiacol, more creosol, phenols, cresols, veratrol, and hydrocarbons. Pure beechwood creosote should not contain any phenols or cresols.