Studies on the Cooperativie Transformation of Hydrogen-Bonds During the Intramolecular First-Order Transitions of Polypeptides-An Application of ^2H NMR Analysis in the Liquid Crystalline State

多肽分子内一级跃迁过程中氢键协同转变的研究——^2H NMR分析在液晶态的应用

• 批准号: 15550111
• 负责人: ABE Akihiro
• 金额: $ 2.5万
• 依托单位: Tokyo Polytechnic University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15550111/
• 关键词: Poly(aspartate)s; Intramolecular hydrogen-bond; Helix-coil transition; Normal transition; Helix-helix transition; _χ1 conformer; Mainchain liquid crystal; Dipole moment; ポリL-アスパルテート; 共重合構造; 分子内転移の相図; 長い側鎖; van der Waals解析; ポリ(α-アミノ酸エステル); ヘリ

1.Screw-sense inversion behaviors (left- to right-handed or vice versa) of α-helical polyaspartates differ substantially depending on the chemical structure (X) of the ester group at the side-chain terminals. The cause of such phenomenological differences among polymers (X=benzyl, chlorobenzyl, and phenethyl) have been investigated by constructing the phase diagram as a function of solvent composition (TCE/TFA) and temperature.2.The helix-coil transition of polyaspartates (X=benzyl and X=phenethyl) in m-cresol at elevated temperature (a normal-type transition) has been studied by NMR methods. The observed ^1H-^1H vicinal coupling constant around the _χ1 bond rotation suggests that the g^- conformation decreases from 〜50% to 〜30% with increasing temperature in the transition region from the left-handed to random-coil state.3.The nematic conformation of main-chain liquid crystals has been studied to examine the possible incorporation of the intramolecular hydrogen-bond. The spectroscopic as well as thermodynamic (PVT) analyses led to a conclusion that a group of partially oriented conformation persists over the entire range of the nematic state. This is an encouraging evidence for the molecular design of a new class of chemical structures.

1.α-螺旋聚天冬氨酸的螺旋翻转行为(从左到右或从左到右)与侧链末端酯基的化学结构(X)有很大的不同。通过构建与溶剂组成(TCE/TFA)和温度的函数关系的相图，研究了聚合物(X=苄基、氯苄基和苯乙基)之间存在这种唯象差异的原因。2.用核磁共振方法研究了聚天冬氨酸(X=苄基和X=苯乙基)在高温下(正常型转变)在间甲酚中的螺旋-螺旋转变。在_χ_1键旋转附近观察到的^1H-^1H邻近耦合常数表明，在从左手到无规卷曲状态的过渡区，g^-构象随着温度的升高从~50%下降到~30%。3.研究了主链液晶的向列构象，考察了分子内氢键的可能并入。光谱和热力学(PVT)分析得出结论，一组部分取向的构象在向列态的整个范围内持续存在。这是一种新的化学结构的分子设计的令人鼓舞的证据。

项目成果

Stepwise Phase Transition of Chain Molecules : Crystallization/Melting via a Nermatic LC Phase

链分子的逐步相变：通过向热 LC 相结晶/熔化

• 发表时间: 2005
• 期刊: Adv.Polym.Sci. (in press)
• 作者: A.Abe;H.Furuya;Z.Zhou;T.Hiejima;Y.Kobayashi
• 通讯作者: Y.Kobayashi

Phase Behavior of Ternary Systems Involving a Conformationally Variable Chain and a Randomly Coiled Polymer

涉及构象可变链和无规卷曲聚合物的三元体系的相行为

• 发表时间: 2003
• 期刊: Macromolecules 36
• 作者: J.Lin;S.lin;P.Liu;T.Hiejima;H.Furuya;A.Abe
• 通讯作者: A.Abe

H.Furuya, H.Iwanaga, T.Nakajima, A.Abe: "Nematic Confirmation of Oxyethylene Spacers Involved in Main-Chain Liquid Crystals"Macromol.Symp.. 192. 239-250 (2003)

H.Furuya、H.Iwanaga、T.Nakajima、A.Abe：“主链液晶中涉及的氧乙烯间隔基的向列确认”Macromol.Symp.. 192. 239-250 (2003)

Effect of the Pendant Ester Group Orientationon the Dipole Moment of Poly(alkyl acrylate)s

侧酯基取向对聚丙烯酸烷基酯偶极矩的影响

• 发表时间: 2003
• 期刊: Macromolecules 36
• 作者: Z.Zhou;A.Abe
• 通讯作者: A.Abe

Screw-sense inversion characteristic of α-helical poly(β-p-chlorobenzyl L-aspartate) and comparison with other related polyaspartates

• DOI: 10.1002/bip.20207
• 发表时间: 2005-01-01
• 期刊: BIOPOLYMERS
• 影响因子: 2.9
• 作者: Abe, A;Hiraga, K;Furuya, H
• 通讯作者: Furuya, H