Captagon Powder

Captagon powder also known as Fenethylline powder is a codrug of amphetamine and theophylline and a prodrug to both. It is also spelled phenethylline and fenetylline (INN); other names for it are amphetamin​oethyl​theophylline and amfetyline. The drug was marketed for use as a psychostimulant under the brand names Captagon, Biocapton, and Fitton.

Fenethylline Powder Pharmacology

The fenethylline molecule results when theophylline is covalently linked with amphetamine by an alkyl chain.

Fenethylline is metabolized by the body to form two drugs, amphetamine (24.5% of oral dose) and theophylline (13.7% of oral dose), both of which are active stimulants. The physiological effects of fenethylline therefore seem to result from a combination of these two compounds, although how is not entirely clear, and seems to involve a synergistic effect between amphetamine and theophylline produced following metabolism.

Fenethylline Synthesis

Theophylline

(1) is alkylated using 2-bromochloroethane

(2) in a substitution reaction to give 7-(2-Chloroethyl)theophylline (aka Benaphyllin, Eupnophile)

(3). 7-(2-Chloroethyl)theophylline forms a three-carbon ring substructure by displacing the remaining halogen leaving group in an intramolecular substitution reaction. The three-carbon ring substructure is deformed by the primary amine in amphetamine

(4), giving fenethylline