Carvacrol

Carvacrol, or cymophenol, C6H3CH3(OH)(C3H7), is a constituent of the ethereal oil of Origanum hirtum, oil of thyme, oil obtained from pepperwort, and wild bergamot. It may be synthetically prepared by the fusion of cymol sulfonic acid with caustic potash; by the action of nitrous acid on 1-methyl-2-amino-4-propyl benzene; by prolonged heating of five parts of camphor with one part of iodine; or by heating carvol with glacial phosphoric acid or by performing a dehydrogenation of carvone with a Pd/C catalyst. It is extracted from Origanum oil by means of a 50% potash solution. It is a thick oil which sets at 20 °C to a mass of crystals of melting point 0°C, and boiling point 236-237 °C. Oxidation with ferric chloride converts it into dicarvacrol, whilst phosphorus pentachloride transforms it into chlorcymol. Carvacrol is the main antibiotic molecule in Oreganos. The percent of carvacrol in raw organo and essential oil preparation is between 2-5% and 40-70% respectivley (mehrdad, 2007).