Mammi N J, Goodman M
Biochemistry. 1986 Nov 18;25(23):7607-14. doi: 10.1021/bi00371a051.
The conformations of five cyclic retro-inverso enkephalin analogues have been probed by proton NMR. After assignment of peaks, intramolecularly hydrogen-bonded amide protons were detected by temperature perturbation. Carbonyl hydrogen-bond acceptors were surmised from the computer simulations of minimum energy conformations of Hassan and Goodman [Hassan, M., & Goodman, M. (1986) Biochemistry (preceding paper in this issue)]. Hydrogen bonds were identified in dimethyl-d6 sulfoxide solutions and monitored as H2O was added. One hydrogen bond was observed in each of the retro-inverso-modified enkephalin analogues although in the parent analogue H-Tyr-c-(D-A2bu-Gly-Phe-Leu) two were detected. The change in solvent altered the conformations of two of the analogues.
通过质子核磁共振对五种环化反向脑啡肽类似物的构象进行了探究。在对峰进行归属后，通过温度扰动检测到分子内氢键结合的酰胺质子。根据哈桑和古德曼[哈桑，M.，&古德曼，M.（1986年）《生物化学》（本期前一篇论文）]最低能量构象的计算机模拟推测出羰基氢键受体。在二甲基-d6亚砜溶液中鉴定出氢键，并在加入水时进行监测。在每种反向脑啡肽类似物中均观察到一个氢键，尽管在母体类似物H-Tyr-c-(D-A2bu-Gly-Phe-Leu)中检测到两个氢键。溶剂的变化改变了其中两种类似物的构象。
