Kanmera T, Izumiya N
Int J Pept Protein Res. 1982 Jan;19(1):79-87.
A cyclic tetradepsipeptide with a sequence corresponding to AM-toxin III (a phytotoxic peptide) was synthesized by a conventional method in order to confirm the proposed structure. This was mediated through a deamination reaction of precursor cyclotetradepsipeptide containing a D-2, 3-diaminopropionic acid residue by the Hofmann degradation method. The synthetic peptide and natural AM-toxin III were identical in regard to t.l.c., crystal form, mass spectrum and biological activity in causing necrosis on apple leaves. Two analogs, [l-O-methyl-L-tyrosine]-AM-toxin and [l-L-tyrosine]-AM-toxin showed extremely weak activity; the relationship between the bulkiness of an aromatic side chain at position 1 of AM-toxin III and its biological activity is discussed.
为了确认所提出的结构，采用传统方法合成了一种序列与AM-毒素III（一种植物毒性肽）相对应的环状四缩肽。这是通过霍夫曼降解法对含有D-2,3-二氨基丙酸残基的前体环四缩肽进行脱氨反应来实现的。合成肽与天然AM-毒素III在薄层层析、晶体形态、质谱以及在苹果叶片上引起坏死的生物活性方面均相同。两种类似物，[1-O-甲基-L-酪氨酸]-AM-毒素和[1-L-酪氨酸]-AM-毒素表现出极其微弱的活性；讨论了AM-毒素III第1位芳香侧链的体积与其生物活性之间的关系。
