Definition. - One of the chief constituents of creosote; prepared either from beechwood tar, or synthetically.

Description and Properties. - Either a clear, colorless or light yellow, oily fluid, or colorless, prismatic crystals, which melt at 28.5o C. It has an agreeable aromatic odor.

Chemically it is the monomethyl ether of pyrocatechin (orthodihydroxy-benzene), C6H4(OH)(OCH3) 1:2.

Soluble in water (1: 53), glycerin (1: 1), and easily in alcohol. Being phenolic in character, it readily dissolves in caustic alkalies and forms salts with a large number of acids, one of which (the carbonate) has been made official. Of late years creosote has been largely superseded by guaiacol, upon which the value of creosote in large part depends.

Dose. - 2-10 minims (0.12-0.6 Cc.) [8 minims (0.5 Cc), U. S. P.].

The following derivatives have been introduced:

Guaiacolis Carbonas - Guaiacolis Carbonatis - Guaiacol Carbonate (U. S. P.). - Definition. - A guaiacol derivative (C6H4(OCH3)O)2.CO, obtained by the action of carbonyl chloride upon sodium-guaiacolate. Also known as duotal.

Description and Properties. - A white, crystalline, neutral powder, nearly odorless and tasteless. Insoluble in water; soluble in cold (1: 48), more so in hot, alcohol; slightly soluble in glycerin and fatty oils.

Dose. - Average dose: 15 grains (1 Gm.), U. S. P.