Method of transforming substituted amides of l-isolysergic and l-lysergic acids into equal derivatives of d-isolysergic and d-lysergic acids

摘要

l(+) - Propanol- and (+) - butanol - amides-(2) of l-isolysergic and l-lysergic acids are transformed into the corresponding derivatives of d-isolysergic and d-lysergic acids by heating for 1 to 10 hours at 110-160 DEG C. until the equilibrium state of diasteroisomers is reached, then separating the derivatives of either d-isolysergic or d-lysergic acid and repeatedly working up the remainder in the same way to an economic degree of exhaustion of the mixture of stereoisomers. In an example the (+)-butanolamide-(2) of l-isolysergic acid is heated for 4 hours at 135-140 DEG C. in the presence of benzylamine under an atmosphere of nitrogen. The residue on treatment with dibenzoyl-d-tartaric acid gives the acid dibenzoyl-d-tartrate of (+)-butanolamide-(2) of d-isolysergic acid (methyl ergobasinine). The acid dibenzoyl-d-tartrate of (+)-butanolamide-(2) of l-isolytergic acid and a molecular compound of (+)-butanolamides-(2) of d- and l-lysergic acid are also isolated. Similar products are obtained using the (+)-butanolamide-(2) of l-lysergic acid in a medium of dl-2-aminobutanol-(1). In further examples, the acid dibenzoyl-d-tartrate of methyl ergobasinine, prepared from its l-isomer by the process of the invention, is converted into the free base which in turn may be epimerized to methyl ergobasine, and ergobasinine is similarly obtained from l(+)-propanolamide-(2) of l-isolysergic acid.