The oxidation of eserine (I) by means of H2O2 and KHCO3 produced the geneseroline carbamate (II), which was hydrolyzed to geneseroline (III) employing 62% sulfuric acid at 85 C. The desired carbamate was then obtained by condensation of (III) with 2-ethylphenyl isocyanate (IV) either in the presence of K2CO3 in acetone or in the presence of t-BuOK under sonication, and the title compound was then isolated as the corresponding hydrochloride salt.

An alternative procedure for the preparation of the intermediate geneseroline (III) consisted in the oxidation of eseretole (V) to geneseretole (VI), followed by ether cleavage by means of concentrated sulfuric acid.

The reaction of 2'-ethylphenserine (I) with MCPBA in chloroform gives the intermediate (II), which is treated in basic medium to yield the target geneserine derivative.