4. , A. , 2. , H. C. Schalley, K. Beizai et al., 01 (d, J = 8.5 Hz, 4H, ArH), 5.56 (s, 2H, OH), 5.52 (s, 2H, OH), 1.37 (s, 18H, C(CH 3 ) 3 ), 1.34 (s, 18H, C(CH 3 ) 3 ). 13 C NMR 50 (125 MHz, CDCl 3 , r.t.): ? 15120 signals out of 21 expected ones) HRMS(ESI): m/z calcd for [M(C 54 H 60 O 4 )?H + ] ? , 771.4413; found 771.4379. 55 Notes and references 1 For recent reviews on molecular machines including molecular 70 motors and artificial muscles using external stimuli, see: (a), Angew. Chem., Int. Ed. Acc. Chem. Res, vol.723, issue.34, pp.31-39, 2000.

. Chem, . Int, . V. Ed, A. Balzani, M. Credi et al., Molecular Devices and Machines: Concepts and Perspectives for the Nanoworld, Chem. Lett. Acc. Chem. Res, vol.46, issue.47, pp.72-92, 2007.

L. Feringa, R. A. Van-delden, N. Koumura, and E. M. Geertsema, Chiroptical Molecular Switches, 2 For reviews on photoresponsive molecular machines, pp.1789-1816, 2000.
DOI : 10.1021/cr9900228

S. Tsuda, Y. Aso, and T. Kaneda, 4 For photoresponsive doubly threaded rotaxanes, see: (a), Chem. Commun, pp.3072-3074, 2006.

. J. Eur, Y. Furusho, T. Tanaka, M. Maeda, E. Ikeda et al., For a photoresponsive double helix, see: (d), Chem. Commun, vol.5, pp.2281-2289, 2007.

T. Katagiri, Y. Miyagawa, E. Furusho, and . Yashima, Synthesis and Optical Resolution of a Double Helicate Consisting ofortho-Linked Hexaphenol Strands Bridged by Spiroborates, Angewandte Chemie International Edition, vol.118, issue.11, pp.1741-1744, 2006.
DOI : 10.1002/anie.200504326

H. Yamamoto, E. Iida, and . Yashima, Guest-Induced Unidirectional Dual Rotary and Twisting Motions of a Spiroborate-Based Double-Stranded Helicate Containing a Bisporphyrin Unit, Angewandte Chemie International Edition, vol.51, issue.27, pp.6849-6853, 2013.
DOI : 10.1002/anie.201302560

S. Shinkai, T. Nakaji, T. Ogawa, K. Shigematsu, and O. Manabe, Photoresponsive crown ethers. 2. Photocontrol of ion extraction and ion transport by a bis(crown ether) with a butterfly-like motion, Journal of the American Chemical Society, vol.103, issue.1, pp.111-115, 1981.
DOI : 10.1021/ja00391a021

H. Kamiya and . Asanuma, Light-Driven DNA Nanomachine with a Photoresponsive Molecular Engine, Accounts of Chemical Research, vol.47, issue.6, pp.1663-1672, 2014.
DOI : 10.1021/ar400308f

J. Yamaji, S. Oshima, M. A. Tobita, W. G. Fourati, C. G. Skene et al., and references therein, J. Org. Chem. J. Phys. Chem. A, vol.70, issue.117, pp.9693-9701, 2005.

D. Grebel-koehler, S. Liu, V. De-feyter, T. Enkelmann, C. Weil et al., Synthesis and Photomodulation of Rigid Polyphenylene Dendrimers with an Azobenzene Core, Macromolecules, vol.36, issue.3, pp.578-590, 2003.
DOI : 10.1021/ma021135n

D. Chai and M. Head-gordon, Long-range corrected hybrid density functionals with damped atom???atom dispersion corrections, Physical Chemistry Chemical Physics, vol.110, issue.44, pp.6615-6620, 2008.
DOI : 10.1039/b810189b
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