Journal of Pharmaceutical Sciences 1981-12-01

Convenient synthesis of 6-nor-9,10-dihydrolysergic acid methyl ester.

A M Crider, R Grubb, K A Bachmann, A K Rawat

Index: J. Pharm. Sci. 70(12) , 1319-21, (1981)

Full Text: HTML

Abstract

6-Nor-9,10-dihydrolysergic acid methyl ester (IV) was prepared by demethylation of 9,10-dihydrolysergic acid methyl ester (II) with 2,2,2-trichloroethyl chloroformate, followed by reduction of the intermediate carbamate (III) with zinc in acetic acid. The 6-ethyl-V and 6-n-propyl-VI derivatives were prepared by alkylation of IV with the appropriate halide. All of the ergoline derivatives were evaluated for stereotyped behavior in rats, with 6-nor-6-ethyl-9,10-dihydrolysergic acid methyl ester (V) being active but much less potent than apomorphine. Compound VI was evaluated for its effect on blood pressure; at a dose of 30 mg/kg ip, it significantly lowered, diastolic pressure in normotensive rats.