Shah D, Schneider A, Babler S, Gandhi R, Van Noord E, Chess E
Abbott Laboratories, Abbott Park, IL 60064.
Pept Res. 1992 Jul-Aug;5(4):241-4.
Alkylation of tryptophan occurred during the synthesis of a 19-amino acid peptide of the following sequence: Tyr Ala Ala Gln Asn Arg Arg Gly Leu Asp Leu Leu Phe Trp Glu Gln Gly Gly Leu. Alkylation was found to occur during cleavage of the peptide from the solid support under acidic conditions in the presence of Tmob, which is used for protecting glutamine and asparagine. Presence of alkylated tryptophan was confirmed by mass spectrometry, HPLC and amino acid sequence analyses.
在合成具有以下序列的19氨基酸肽（Tyr Ala Ala Gln Asn Arg Arg Gly Leu Asp Leu Leu Phe Trp Glu Gln Gly Gly Leu）的过程中，色氨酸发生了烷基化。发现在酸性条件下，在用于保护谷氨酰胺和天冬酰胺的Tmob存在的情况下，从固相载体上切割肽时会发生烷基化。通过质谱、高效液相色谱和氨基酸序列分析证实了烷基化色氨酸的存在。
