Folding of aromatic amide-based oligomers induced by benzene-1,3,5-tricarboxylate anion in DMSO.
In this paper, we describe the folding of a series of linear arylamide oligomers in DMSO that is induced by benzene-1,3,5-tricarboxylate anion. The oligomers are comprised of naphthalene-2,7-diamine and 1,3,5-benzenetricarboxylic acid segments with two (tert-butoxycarbonylamino) groups at the ends and two to four hydrophilic N,N-bis(2-(2-(2-methoxyethoxy)ethoxy)ethyl)amino groups at one side of the backbones. (2D NOESY) (1)H NMR, fluorescence and UV-vis studies indicate that the oligomers do not adopt defined conformations in DMSO but fold into compact structures in the presence of the anion. It is revealed that the folded conformation is induced by intermolecular hydrogen bonds between the amide and aromatic hydrogen atoms of the oligomers and the oxygen atoms of the anion. (1)H NMR and UV-vis titrations support a 1:1 binding stoichiometry, and the associated constants are determined, which are found to increase with the elongation of the oligomers.
State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Lu, Shanghai 200032, China.
Yun-Xiang
YX
Xu
Gui-Tao
GT
Wang
Xin
X
Zhao
Xi-Kui
XK
Jiang
Zhan-Ting
ZT
Li
D000577:Amides / Q000138:chemical synthesis / Q000737:chemistry; D000838:Anions / Q000737:chemistry; D003500:Cyclization; D004121:Dimethyl Sulfoxide / Q000737:chemistry*; D008968:Molecular Conformation; D013237:Stereoisomerism; D014233:Tricarboxylic Acids / Q000737:chemistry*
D000577:Amides; D000838:Anions; D014233:Tricarboxylic Acids; C069849:trimesic acid; D004121:Dimethyl Sulfoxide