Synthetic cathinones form a family of drugs that has recently thrived in the illegal market, a phenomenon that has been facilitated by clandestine Internet sites, which permitted their sale and distribution, taking advantage of the lack of legislation on these activities for this type of compounds (Winstock et al., 2011). Nonetheless, cathinone derivatives have existed for approximately a century. Cathinone and its metabolite cathine are responsible for the sympathomimetic amphetamine-like effects caused by the chewing of khat (Catha edulis) leaves, a plant which grows primarily in East African countries such as Somalia, Ethiopia, Uganda and Kenya, as well as in Yemen in the Middle East, where its use is deeply embedded as part of the local culture. There, approximately 50% of the adult population is believed to consume khat daily (90% in male adults).
Cathinone is the reference structure from which a great number of compounds have derived. It is closely related to amphetamine, from which it is differentiated by the addition of a ketone group on the β position of the aliphatic chain.
4-methylmethcathinone (Mephedrone, Meph), 3,4-methylenedioxy-N- methylcathinone (methylone), methylenedioxypyrovalerone (MDPV) and bupropion are the most widely used cathinone derivatives. Bupropion is a commercialized compound, prescribed mostly for depression and smoking cessation, although it has other off-label uses. By contrast, the former three compounds are consumed primarily for recreational purposes. Fig. 3 depicts their chemical structure and that of cathinone.