Methylecgonidine

Methylecgonidine (anhydromethylecgonine; anhydroecgonine methyl ester) is a chemical intermediate derived from ecgonine or cocaine.

Methylecgonidine is a pyrolysis product formed when crack cocaine is smoked, making this substance a useful biomarker to specifically test for use of crack cocaine, as opposed to powder cocaine which does not form methylecgonidine as a metabolite. Methylecgonidine has a relatively short half-life of 18-21 minutes, after which it is metabolised to ecgonidine, meaning that the relative concentrations of the two compounds can be used to estimate how recently crack cocaine has been smoked. Methylecgonidine has been shown to be specifically more harmful to the body than other byproducts of cocaine; for example to the heart, lungs & liver.

It is also used in scientific research for the manufacture of phenyltropane analogues such as Troparil, Lometopane and CFT. Methylecgonidine could also theoretically be used to produce cocaine and so may be a controlled substance in some countries.

When methylecgonidine is made synthetically for research purposes, it is usually produced by reacting cocaine or ecgonine with hydrochloric acid, yielding ecgonidine (anhydroecgonine), followed by methylation to yield methylecgonidine. Alternatively it can be made in a two step reaction by reacting 2,4,6-cycloheptatriene-7-carboxylic acid with first a mixture of methylamine and sodium hydroxide, followed by reaction with a mixture of methanol and sulfuric acid.