Abstract The N-methyl-N-propyl, N-methyl-N-isopropy, N-butyl, N-isobutyl, N-sec-butyl and N-tert-butyl amides of lysergic acid were synthesized to determine the specificity of electron impact mass spectroscopy (EI/MS), when combined with other analytical techniques, for the identification of lysergic acid diethylamide (LSD). After separation of the C8 axial and equatorial isomers by preparative...