Tuning Binding Strength by Varying the Number of Interstrand H Bonds

TUNING BINDING STRENGTH BY VARYING THE NUMBER OF INTERSTRAND H BONDS 

The formation of duplex 3 4 was confirmed by 1-D and 2-D H-NMR. In CDCI3, the H-NMR spectrum of the 1 1 mixture of 3 and 4 revealed very large (2-3 ppm) downfield shifts of the aniline NH signals compared to those of strands 3 or 4 alone. The association constant of 3 4 was so high that attempts to measure it by H-NMR 

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