pubmed-article:738697 | pubmed:abstractText | The tert-butylation of free tryptophan under simulated conditions of acidolytic cleavage of protecting groups being based on a tert-butyl moiety does finally yield the tri-substituted amino acid as a main product, namely 2,5,7-tri-tert-butyltryptophan. The structural elucidation of this substance and other tert-butylated products, which were isolated mostly in a pure form, was achieved by means of spectroscopic methods, in particular mass spectrometry and nuclear magnetic resonance spectroscopy. | lld:pubmed |