Phenol chemistry, formulations and adjuvants

Medicine has made wide use of phenols in many indications, as we shall see later in this book. Medical publications on peels aboimd in terms that are no longer in use and names of outdated molecules, which makes some texts difficult to read. It is therefore worthwhile taking a quick look at what these terms and compoimds correspond to. 

Chemical structures of ortho-creso (a), meto-cresol (b) and pora-cresol (c). 

Halogenated phenols are more powerful disinfectants than simple phenols, as they are more lipophilic. They are also more toxic to the central nervous system. The chlorinated phenols are the most active. Toxicity is specific to each compound. 

Bisphenols (not to be confused with the diphenols), are formed by two phenols linked with a bridge (-CHj-, -O-or -S-) in the ortho position, which makes the product easier to tolerate. Bisphenols are often chlorinated to increase their disinfectant power. Dichlorophene, tetrachlorophene 

Chemical structures of salicylic acid (a) and para-hydroxybenzoic acid (b). 

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