Identification of Absolute Helical Structures of Aromatic Multilayered Oligo(<i>m</i>-phenylurea)s in Solution
作者:Mayumi Kudo、Takayuki Hanashima、Atsuya Muranaka、Hisako Sato、Masanobu Uchiyama、Isao Azumaya、Tomoya Hirano、Hiroyuki Kagechika、Aya Tanatani
DOI:10.1021/jo901934r
日期:2009.11.6
all-S axis chirality) when the benzene rings are connected at the meta positions. The absolute helical structure of oligo(m-phenylurea)s were identified by the empirical and theoretical studies on the CD and vibrational CD (VCD) spectra. Thus, each enantiomer of the oligo(m-phenylurea)s 4 bearing a chiral N-2-(methoxyethoxyethoxy)propyl group were synthesized. Intense dispersion-type CD spectra of 4 were
带有N,N'-二甲基化脲键的低聚芳香族脲(如3)具有(顺,顺)脲结构的芳香多层结构,并且具有动态螺旋结构(all- R或all- S轴手性)。当苯环在间位连接时。寡核苷酸的绝对螺旋结构(米苯基脲)类是由CD和振动CD(VCD)光谱上的经验和理论研究确定。因此,低聚(的各对映体米苯基脲)■ 4轴承手性Ñ合成了-2-(甲氧基乙氧基乙氧基)丙基。观察到强分散型CD光谱为4,这表明在螺旋结构中产生了旋顺性。在膜态的4的VCD光谱中,化合物4a和4b的羰基和芳环振动信号分别为负值和正值。CD和低聚(VCD的光谱的计算米苯基脲)类3而没有任何手性ñ -取代给有关的轴线手性相同的分配4。因此,4a和4b的绝对配置都是-R和全S结构分别。