Berman J M, Goodman M
Int J Pept Protein Res. 1984 Jun;23(6):610-20.
The cyclic partial retro-inverso modified enkephalins, H-Tyr-cyclo[-D-Glu-Gly-gPhe-D-Leu-] (I), H-Tyr-cyclo[-D-A2bu-Gly-gPhe-R&S-mLeu-] (IIf, IIs), and H-Tyr-cyclo[-D-Glu-Gly-Phe-gLeu-] (III), have been synthesized by solution methodology. In a like manner, their corresponding acyclic analogs Ia-IIIa containing D-Ala2 have also been prepared. Gem-diaminoalkyl residues were generated by conversion of Boc-dipeptide carboxamide to the corresponding gem-diaminoalkyl "dipeptide" salt using [bis(trifluoroacetoxy)iodo] benzene. Cyclizations were achieved at high dilution utilizing diphenylphosphoryl azide as the coupling reagent.
通过溶液法合成了环状部分反转异构修饰脑啡肽，即H-Tyr-环[ -D-Glu-Gly-gPhe-D-Leu-]（I）、H-Tyr-环[ -D-A2bu-Gly-gPhe-R&S-mLeu-]（IIf、IIs）和H-Tyr-环[ -D-Glu-Gly-Phe-gLeu-]（III）。同样地，还制备了含有D-Ala2的相应非环状类似物Ia - IIIa。使用[双（三氟乙酰氧基）碘]苯将Boc - 二肽羧酰胺转化为相应的偕二氨基烷基“二肽”盐，从而生成偕二氨基烷基残基。利用二苯基磷酰叠氮作为偶联剂，在高稀释条件下实现环化。
