Biosynthesis of N-(α-hydroxyethyl)-lysergamide, a metabolite of Claviceps paspali Stevens & Hall

Abstract

1. The biosynthetic origin of the amide substituent of N-(α-hydroxyethyl)lysergamide has been studied. 2. [1-14C]Acetate, [14C]formate, [2-14C]mevalonic acid lactone, [2-14C]indole, dl-[3-14C]tryptophan, dl-[3-14C]serine, dl-[2-14C]alanine and [2-14C]pyruvate were efficiently incorporated into the alkaloid, but not dl-[1-14C]alanine or [1-14C]pyruvate. 3. Only the dl-[2-14C]alanine- and [2-14C]pyruvate-derived alkaloid contained appreciable radioactivity in the amide substituent. 4. l-[15N]Alanine-derived alkaloid was shown to be specifically labelled in the amide nitrogen. However, l-[14C,15N]alanine was found to be incorporated into the methylcarbinolamide substituent with an appreciable increase in the 15N/14C ratio, suggesting that alanine is not the direct precursor of this moiety.