39874 2017 eng 373 376 3 12 article NPC Westerville, Ohio, USA 1 -- -- -- The priority ergot alkaloids ergometrine and ergometrinine are highly toxic mycotoxins naturally occurring in different types of grains (i.e. rye, wheat, rice), as well as grain-based foods and, therefore, have gained increasing importance for food safety over the last years. The application of HPLC-MS/MS for the analysis of ergot alkaloids in food presupposes the availability of isotopically labelled internal standards. Thus, a multistep synthesis was developed for ergometrine-(N-13CD3) and its epimer ergometrinine-(N-13CD3) with a mass shift of four units compared with the parent compounds. The synthesis is based on the preparation of stable isotope labelled lysergic acid that was coupled with (S)-alaninol. The chemical synthesis of both compounds has been achieved in six steps with an overall yield of 1 % (ergometrine-(N-13CD3)) and 0.6 % (ergometrinine-(N-13CD3)), respectively. Structural identification was performed by MS analysis as well as 1H and 13C NMR. Natural Product Communications (NPC) 1934-578X 1555-9475 18.04.2017 Robert Köppen B. Braun C. Wedler F. Theil eng uncontrolled Ergometrine-(N-13CD3) eng uncontrolled Ergometrinine-(N-13CD3) eng uncontrolled Mycotoxin eng uncontrolled Ergot alkaloids eng uncontrolled Analytical standard eng uncontrolled Stable isotope dilution analysis (SIDA) Analytische Chemie Verlagsliteratur Datei im Netzwerk der BAM verfügbar ("Closed Access")