The effect of alcohols on the basic cleavage of m-nitrophenyl hexanoate by β-cyclodextrin: allosteric reaction mode switching

Abstract

Evidence is presented of a reacting guest–host system where binding of an ‘allostere' to the host inhibits its reaction with the guest by one particular mode and promotes its reaction by another. Simple aliphatic alcohols do not slow down the basic cleavage of m-nitrophenyl hexanoate by β-cyclodextrin (β-CD) to the extent required for competitive inhibition and so an additional, alcohol-mediated reaction must be taking place. Rate constants for this process correlate well with the ability of the alcohol to bind to β-CD, as do those for the analogous reaction of p-nitrophenyl hexanoate, suggesting that the alcohol is in the cavity of β-CD during the reaction. Transition state binding parameters for the alcohol-mediated reaction of the two nitrophenyl esters are very similar, and they show the same dependence on the binding ability of the alcohols. Overall, the results are consistent with a switch in the mode of reaction from cleavage of m-nitrophenyl hexanoate by aryl group inclusion (1) to its cleavage by acyl group inclusion (2), brought about by binding of a simple alcohol, acting as an ‘allostere'.

References

1. A. Fersht, Enzyme Structure and Mechanism, W. H. Freeman, New York, 2nd edn., 1985.
2. (a) K. G. Scrimgeour, Chemistry and Control of Enzyme Reactions, Academic Press, London, 1977; (b) P. C. Engel, in The Chemistry of Enzyme Action, ed., M. I. Page, Elsevier, Amsterdam, 1984; (c) J. Stenesh, Dictionary of Biochemistry and Molecular Biology, Wiley, New York, 1989; (d) A. Cooper and D. Dryden, in The Enzyme Catalysis Process: Energetics, Mechanism and Dynamics, eds., A. Cooper, J. L. Houben and L. C. Chien, Plenum Press, New York, 1989.
3. (a) O. S. Tee and J. J. Hoeven, J. Am. Chem. Soc., 1989, 111, 8318; (b) O. S. Tee, M. Bozzi, J. J. Hoeven and T. A. Gadosy, J. Am. Chem. Soc., 1993, 115, 8990.
4. (a) O. S. Tee and M. Bozzi, J. Am. Chem. Soc., 1990, 112, 7815; (b) O. S. Tee, M. Bozzi, N. Clement and T. A. Gadosy, J. Org. Chem., 1995, 60, 3509.
5. (a) O. S. Tee and M. J. Boyd, J. Chem. Soc. Perkin Trans. 2, 1995, 1237; (b) T. A. Gadosy and O. S. Tee, Can J. Chem., 1996, 74, 745; (c) O. S. Tee and R. A. Donga, J. Chem. Soc., Perkin Trans. 2, 1996, 2763.
6. (a) M. Bender and M. Komiyama, Cyclodextrin Chemistry, Springer Verlag, New York, 1978; (b) J. Szejtli, Cyclodextrins and their Inclusion Complexes, Akademiai Kiado, Budapest, 1982.
7. Y. Matsui, T. Nishioka and T. Fujita, Top. Curr. Chem., 1985, 128, 61.
8. G. M. Bonora, R. Fornasier, P. Scrimin and U. Tonellato, J. Chem. Soc., Perkin Trans. 2, 1985, 367.
9. O. S. Tee, C. Mazza and X.-X. Du, J. Org. Chem., 1990, 55, 3603.
10. (a) O. S. Tee, Carbohydr. Res., 1989, 192, 181; (b) O. S. Tee, Adv. Phys. Org. Chem., 1994, 29, 1.
11. (a) T. A. Gadosy and O. S. Tee, J. Chem. Soc., Perkin Trans. 2, 1994, 715; (b) O. S. Tee and T. A. Gadosy, J. Chem. Soc., Perkin Trans. 2, 1994, 2191.
12. (a) R. L. VanEtten, J. F. Sebastian, G. A. Clowes and M. L. Bender, J. Am. Chem. Soc., 1967, 89, 3242; (b) R. L. VanEtten, G. A. Clowes, J. F. Sebastian and M. L. Bender, J. Am. Chem. Soc., 1967, 89, 3253.
13. (a) O. S. Tee, T. A. Gadosy and J. B. Giorgi, J. Chem. Soc., Perkin Trans. 2, 1993, 1705; (b) O. S. Tee, T. A. Gadosy and J. B. Giorgi, Can. J. Chem., 1996, 74, 736; (c) O. S. Tee, A. A. Fedortchenko, P. G. Loncke and T. A. Gadosy, J. Chem. Soc., Perkin Trans. 2, 1996, 1243; (d) Cf. P. M. Demont and V. C. Reinsborough, Aust. J. Chem., 1991, 44, 759.
14. Y. Matsui and K. Mochida, Bull. Chem. Soc. Jpn., 1979, 52, 2808.
15. (a) R. I. Gelb, L. M. Schwartz, M. Radeos, R. B. Edmonds and D. A. Laufer, J. Am. Chem. Soc., 1982, 104, 6283; (b) G. Barone, G. Castronuovo, P. Del Vecchio, V. Eli and M. Muscetta, J. Chem. Soc., Faraday Trans. 1, 1986, 82, 2089; (c) H. Fujiwara, H. Arawaka, S. Muarata and Y. Sasaki, Bull. Chem. Soc. Jpn., 1987, 60, 3891.
16. (a) J. L. Kurz, J. Am. Chem. Soc., 1963, 85, 987; Acc. Chem. Res., 1972, 5, 1; (b) G. E. Lienhard, Science, 1973, 180, 149; (c) J. Kraut, Science, 1988, 242, 533.
17. A. J. Kirby, Angew. Chem., Int. Ed. Engl., 1996, 35, 707.
18. X.-X. Du and M. Sc. Thesis, Concordia University, Montréal, Canada, 1989.