Molecular Complexes for the Study of Enantiodiscriminative Processes

The structure of the molecular complex between the chiral selector (+)1-(3-allylpropyl)-(5R,8S,10R)-N,N-diethyl-N’-[6-methylergolin-8-yl]urea, C23H33N4O, (allyl-terguride) and the more retained (S)-isomer of dansyl-serine, C15H19N2O5S, has been determined. It is part of a study on the chiral recognition mechanism of ergot alkaloids, when used in chiral stationary phases for the separation of racemic mixture of organic acids by liquid chromatographic methods. At the pH of the crystallisation conditions, which mimick those corresponding to the best enantiodiscrimi-native activity, each molecule of (S)-dansyl-serine is locked by hydrogen bonds between two translation related molecules of allyl-terguride forming a infinite chains in a 1:1 molecular ratio.