@We have been studying on the design and synthesis of helical molecules, supramolecules, and polymers with novel structures including double helical structures and specific functions. In 1995, we discovered an unprecedented macromolecular helicity induction with a controlled helix-sense and memory of the helical chirality in optically inactive Î-conjugated polymers through noncovalent bonding interactions. Taking advantage of this helicity induction and memory concept, we developed novel chirality sensing systems to target chiral molecules by means of circular dichroism (CD) spectroscopy. We also discovered inversion of helicity of dynamic helical polymers by responding to chiral stimuli, which provides a conceptually new chirality-sensing method. Thereafter, we developed a fascinating method to directly observe the helical structures of several helical polymers by high-resolution atomic force microscopy (AFM), which enabled to determine the helical structures including helical pitch, handedness (right or left), and helical sense excess as well.
@In 2005, we successfully synthesized the first single-handed double helices consisting of complementary molecular strands through formation of salt bridges. We further developed the first supramolecular catalysts based on complementary double helical molecules that can catalyze asymmetric reactions with high enantioselectivity. Thereafter, we have prepared a series of double helices composed of different components and sequences that exhibit specific functions, such as chirality sensing, chiral recognition and separation, anisotropic spring-like motion, and also a unique dendritic metallopeptide in which chirality is harvesting via remote-stereocontrol. Our achievements are described in more detail below.