Conformation of cyclo-(D-phenylalanyl-trans-4-fluoro-D-prolyl).
Conformation of cyclo-(D-phenylalanyl-trans-4-fluoro-D-prolyl).
复制标题
环-(D-苯丙氨酰-反-4-氟-D-脯氨酰)的构象。
DOI：
10.1111/j.1399-3011.1990.tb00980.x
复制
发表时间：
2009
期刊：
影响因子：
--
通讯作者：
M. Anteunis
中科院分区：
文献类型：
--
作者：
J. Ciarkowski;M. Gdaniec;A. Kolodziejczyk;B. Liberek;F. Borremans;M. Anteunis
合成了环（D-苯丙氨酰-反式-4-氟-D-脯氨酰）c（D-Phe-D-FPro），并通过~ 1H NMR和X-射线衍射分别确定了其在溶液和固体中的构象。在晶体中，对于含有Pro残基的环二肽，2，5-二酮哌嗪（DKP）环呈现不常见的扁平椅状构象，这似乎是由于一方面DKP-芳香族分子内环-环吸引力（折叠）（要求Phe的C α-C β键是轴向的）与另一方面DKP-芳香族分子内环-环吸引力（折叠）之间的折衷而产生的。Pro残基使其C α-C β键平伏的内在趋势。与固态不同，CDCl 3和C6 D 6中的1H NMR数据表明，在这两种溶液中，DKP环呈现船状形状，典型的含Pro的环二肽，在两个氨基酸残基中具有赤道C α-C β键，这排除了环-环折叠。在c（D-Phe-D-FPro）的最接近的类似物中，即在c（Phe-Pro）中，在溶液（21，22，26）和固体状态（12）中，都遇到了类似的构象。一个微妙的相互作用的分子内相互作用引入到环二肽的Pro型和苯丙氨酸型残基被强调。
cyclo(D-Phenylalanyl-trans-4-fluoro-D-prolyl), c(D-Phe-D-FPro), was synthesized and its conformation determined both in solution and in the solid state by 1H NMR and X-ray analysis, respectively. In the crystals the 2.5-diketopiperazine (DKP) ring assumes the uncommon conformation, for cyclodipeptides containing Pro residue, of a flattened chair, which seemingly results from a compromise between, on the one hand, the DKP-aromatic intramolecular ring-ring attraction (folding), requiring the C alpha--C beta bond of the Phe to be axial, and, on the other hand, the intrinsic tendency of the Pro residue to have its C alpha--C beta bond equatorial. Unlike the solid state, the 1H NMR data in CDCl3 and C6D6 demonstrate that in both solutions the DKP ring assumes a boat-like shape, typical for the Pro-containing cyclodipeptides, with the equatorial C alpha--C beta bonds in both amino acid residues, which preclude ring-ring folding. A similar conformation was encountered in the closest analog of c(D-Phe-D-FPro), viz, in c(Phe-Pro), both in solution (21, 22, 26) and in the solid state (12). A subtle interplay of intramolecular interactions introduced into a cyclodipeptide by a Pro-type and a Phe-type residue is emphasized.
环-L-胱氨酸的晶体结构和构象。
DOI：
10.1111/j.1399-3011.1981.tb02043.x
发表时间：
1981
期刊：
International journal of peptide and protein research
影响因子：
--
作者：
Varughese,KI;Lu,CT;Kartha,G
通讯作者：
Kartha,G