INTRAMOLECULAR HYDROGEN-BONDING IN DERIVATIVES OF BETA-ALANINE AND GAMMA-AMINO BUTYRIC-ACID - MODEL STUDIES FOR THE FOLDING OF UNNATURAL POLYPEPTIDE BACKBONES
INTRAMOLECULAR HYDROGEN-BONDING IN DERIVATIVES OF BETA-ALANINE AND GAMMA-AMINO BUTYRIC-ACID - MODEL STUDIES FOR THE FOLDING OF UNNATURAL POLYPEPTIDE BACKBONES
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DOI：
10.1021/ja00082a029
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发表时间：
1994-02-09
影响因子：
15
通讯作者：
GELLMAN, SH
中科院分区：
文献类型：
--
作者：
DADO, GP;GELLMAN, SH
我们已经研究了简单的β-和γ-氨基酸衍生物的分子内氢键行为，作为设计非天然聚酰胺的努力的前奏，这些聚酰胺将采用类似于α-氨基酸聚合物（蛋白质）的紧凑和特定的折叠模式。我们假设，如果聚合物骨架上最近邻的酰胺基团之间的分子内氢键是不利的，则最有可能实现所需的折叠行为。以前其他实验室和我们自己的工作表明，这一标准适用于α-氨基酸聚合物。本文报道的β-丙氨酸衍生物在二氯甲烷中的变温FT-IR数据表明，最近邻氢键也不利于这种类型的残基。然而，γ-氨基丁酸衍生物的FT-IR和NMR数据表明，最近邻氢键是有利的。对于这里讨论的二酰胺，热力学参数已被确定为氢键介导的折叠通过变温FT-IR测量。这些Δ H度和Δ S度值应该为分子力学程序提供有用的基准。
We have examined the intramolecular hydrogen bonding behavior of simple beta- and gamma-amino acid derivatives as a prelude to efforts to design unnatural polyamides that will adopt compact and specific folding patterns analogous to those of alpha-amino acid polymers (proteins). We postulate that the desired folding behavior will be most likely if intramolecular hydrogen bonds are unfavorable between nearest neighbor amide groups on the polymer backbone. Previous work from other laboratories and our own has shown that this criterion applies to alpha-amino acid polymers. Variable-temperature FT-IR data reported here for beta-alanine derivatives in methylene chloride indicate that nearest neighbor hydrogen bonding is unfavorable for this type of residue as well. FT-IR and NMR data for gamma-amino butyric acid derivatives, however, show that nearest neighbor hydrogen bonding is favorable. For two of the diamides discussed here, thermodynamic parameters have been determined for hydrogen-bond-mediated folding via variable-temperature FT-IR measurements. These Delta H degrees and Delta S degrees values should provide useful benchmarks for molecular mechanics programs.