Total structure of hormothamnin A, A toxic cyclic undecapeptide from the tropical marine cyanobacterium hormothamnion enteromorphoides
作者:William H. Gerwick、Zhi D. Jiang、Santosh K. Agarwal、Bennett T. Farmer
DOI:10.1016/s0040-4020(01)88753-6
日期:1992.3
LE-L-LEU, obtained under partial hydrolysis conditions, was instrumental to the final structure determination. β-D-aminooctanoic acid (D-BAOA) was characterized as a per-ester derivative following complete acid hydrolysis and Z-didehydrohomoalanine (DHHA) was spectroscopically in the intact peptide. The remaining residues (HYPRO, 2 × HSER, GLY) were evident from amino acid and spectroscopic analysis
热带海洋蓝藻Hormothamnion enteromorphoides产生一系列细胞毒性和抗菌性环状肽。其中最具亲脂性的激素是香豆素A,其结构是通过物理数据的解释(主要是高NMR和FAB MS)以及化学衍生和降解方案来确定的。一个关键五肽片段的隔离d PHE- d -LEU-大号-ILE- d -同种异体-ILE-大号-Leu,部分水解的条件下得到,是有助的到最终结构测定。β- D-氨基辛酸(D-BAOA)表征为在完全酸水解后的过酸酯衍生物,并且在完整肽段中通过光谱分析了Z-二氢脱氢高丙氨酸(DHHA)。从氨基酸和光谱分析中可以明显看出剩余的残留物(HYPRO,2×HSER,GLY)。这些残基的测序利用了来自片段,完整肽的高场NMR(NOESY和ROESY)和FAB MS分析的知识。α-氨基残基的绝对立体化学通过用Marfey's试剂衍生的酸释放残基的HPLC分析来确定。通过圆二色性分析