7438
Y. Kubo et al. / Tetrahedron Letters 42 (2001) 7435–7438
Scheme 2.
5. Ikeda, M.; Shinkai, S.; Osuka, A. Chem. Commun. 2000,
1043.
6. (a) Yuasa, H.; Hashimoto, H. J. Am. Chem. Soc. 1999,
121, 5089; (b) Krauss, R.; Weinig, H.-G.; Seydack, M.;
Bendig, J.; Koert, U. Angew. Chem., Int. Ed. 2000, 39,
1835 and references cited therein.
7. Recently, Glass demonstrated that an ethynylene-linked
trityl derivative shows cooperative silver ion recognition.
See: Glass, T. E. J. Am. Chem. Soc. 2000, 122, 4522.
8. For recent dimeric porphyrins for amine recognition, see:
(a) Yagi, S.; Yonekura, I.; Ezoe, M.; Takagishi, T. Chem.
Commun. 2001, 557; (b) Kurtan, T.; Nesnas, N.; Li,
Y.-Q.; Huang, X.; Nakanishi, K.; Berova, N. J. Am.
Chem. Soc. 2001, 123, 5962; (c) Kurtan, T.; Nesnas, N.;
Koehn, F. K.; Li, Y.-Q.; Nakanishi, K.; Berova, N. J.
Am. Chem. Soc. 2001, 123, 5974 and references cited
therein.
These findings clearly show that once the first pair of
porphyrins binds the first DPP in their cleft, the second
pair of porphyrins enhances its affinity toward the
second DPP. This is due to preorganization and align-
ment of the second binding site, i.e. a butadiynyl rota-
tional axis in 1 can act as an efficient transducer of the
binding information (Scheme 2).
In conclusion, we have demonstrated that 1 is a novel
scaffold for the design of a positive homotropic
allosteric systems with a Hill coefficient of 1.9. Addi-
tionally, the subunits for guest binding, which are ratio-
nally arranged around the rotational axis such as metal
ions or butadiynylene, would work cooperatively to
bind guest molecules in a nonlinear fashion. One can
readily apply this system to more complex oligomeric
or polymeric binding-site systems, e.g. for constructing
highly sensitive and selective sensory materials. These
studies are now in progress in our group.
9. Hundermark, T.; Littke, A. F.; Buchward, S. L.; Fu, G.
C. Org. Lett. 2000, 2, 1729.
10. Compound 1: mp >300°C; MALDI-TOF MS (dithranol)
m/z 3867.91 ([M+H]+=3868.41); 1H NMR (600 MHz,
CDCl3, TMS, 25°C): l/ppm 0.98 (t, 12H), 1.10 (m, 24H),
1.48 (m, 8H), 1.65 (m, 16H), 1.75 (m, 8H), 1.97 (m, 16H),
3.95 (t, J=6.0, 8H), 4.16 (t, J=6.2, 4H), 4.24 (t, J=6.0,
8H), 4.28 (t, J=6.3, 4H), 7.04 (d, J=7.9, 8H), 7.08 (d,
J=6.0, 4H), 7.24 (m, 8H), 7.28 (m, 4H), 7.60 (d, J=7.7,
2H), 7.66 (m, 6H), 7.86 (s, 4H), 7.91 (s, 4H), 7.98 (s, 2H),
7.99 (d, J=7.3, 8H), 8.07 (d, J=7.6, 8H), 8.11 (d,
J=7.3, 4H), 8.14 (d, J=7.4, 4H), 8.31 (d, J=7.1,
4H) and 8.74–8.98 (m, 32H). Anal. calcd for
References
1. (a) Rebek, Jr., J. Acc. Chem. Res. 1984, 17, 258; (b)
Nabeshima, T. Cood. Chem. Rev. 1996, 148, 151; (c)
Shinkai, S.; Sugasaki, A.; Ikeda, M.; Takeuchi, M. Acc.
Chem. Res. 2001, 34, 494 and references cited therein.
2. (a) Changeux, J.-P.; Edelstein, S. J. Neuron 1998, 21, 959;
(b) Wyman, J.; Gill, S. J. Binding and Linkage; Univ. Sci.
Books: Mill Valley, CA, 1990.
C
248H218N16O12Zn4·0.5CHCl3: C, 75.83; H, 5.60; N, 5.69.
3. Mattevi, A.; Rizzi, M.; Bolognesi, M. Curr. Opin. Struc.
Biol. 1996, 6, 824.
Found: C, 75.48; H, 5.61; N, 5.53%.
11. Guest binding leads to conformational restriction of host
fluorophore with increasing fluorescence intensity. See:
(a) McFarland, S. A.; Finney, N. S. J. Am. Chem. Soc.
2001, 123, 1260; (b) Takeuchi, M.; Mizuno, T.; Shinmori,
H.; Nakashima, M.; Shinkai, S. Tetrahedron 1996, 52,
1195; (c) Sandanayake, K. R. A. S.; Nakashima, K.;
Shinkai, S. J. Chem. Soc., Chem. Commun. 1994, 1621.
12. (a) Perlmutter-Hayman, B. Acc. Chem. Res. 1986, 19, 90;
(b) Connors, K. A. Binding Constants; John Wiley &
Sons: New York, 1987.
4. (a) Takeuchi, M.; Imada, T.; Shinkai, S. Angew. Chem.,
Int. Ed. 1998, 37, 2096; (b) Ikeda, M.; Takeuchi, M.;
Sugasaki, A.; Robertson, A.; Imada, T.; Shinkai, S.
Supramol. Chem. 2000, 12, 321; (c) Ikeda, M.; Tanida, T.;
Takeuchi, M.; Shinkai, S. Org. Lett. 2000, 2, 1803; (d)
Sugasaki, A.; Ikeda, M.; Takeuchi, M.; Koumoto, K.;
Shinkai, S. Tetrahedron 2000, 56, 4717; (e) Sugasaki, A.;
Ikeda, M.; Takeuchi, M.; Shinkai, S. Angew. Chem., Int.
Ed. 2000, 39, 3839; (f) Robertson, A.; Ikeda, M.;
Takeuchi, M.; Shinkai, S. Bull. Chem. Soc. Jpn. 2001, 74,
739; (g) Yamamoto, M.; Sugasaki, A.; Ikeda, M.;
Takeuchi, M.; Frimat, K.; James, T. D.; Shinkai, S.
Chem. Lett. 2001, 520.
13. We have found that piperidine binding to 1 results in a
fluorescence maximum shift (from 608 to 617 nm) and
the intensity decreases. This is the reason why we chose
piperidine as a competing monoamine guest.