Abstract
2,5-Diketopiperazines were prepared and characterized where one of the amino acids is (2S,3R,4R,5S)-3,4,5-trihydroxypipecolic acid. The protected pipecolic acid was synthesized from a selectively protected deoxynojirimycin derivative. The ring closure to give the diketopiperazines, from the dipeptides, was performed by nucleophilic attack of the amino function of the pipecolic acid moiety onto the carbonyl group of the methyl esters.
Graphical Abstract
Acknowledgements
The author gives thanks to Prof G. W. J. Fleet for his interest and help and to Mrs. Roczkov Ivánné for performing combustion analysis furthermore, to RCNS-HAS for financial support..
Supplementary data
Supporting information (detailed experimental descriptions for all new compounds, NMR and MS spectra, LCMS chromatograms) associated with this article can be found via the “Supplementary Content” section of this article’s webpage.