Sage Journals: Discover world-class research

Abstract

The usefulness of the 2D-NMR techniques in the structure determination of the oligo ε-caprolactone ethyl glucopyranoside (oilgo(ε-CL) EGP) conjugate, synthesized by a lipase-catalyzed regioselective reaction, is described. Data from a ¹³C–¹³C COSY NMR spectrum of the ethyl glucopyranoside is used for complete and unambiguous assignments of the carbon resonances in the ¹³C NMR spectrum of the anomeric mixture of EGP. A comparison of the DEPT-135 spectrum of the product oilgo(ε-CL) EGP conjugate with that of the starting material, ethyl glucopyranoside (EGP), led to the conclusion that the lipase-catalyzed ring-opening of ε-CL initiated by a multifunctional initiator, EGP, proceeded in a regioselective fashion. Also, a detailed analysis of the NMR data has allowed determination of the site for lipase-catalyzed ring-opening polymerization of ε-CL. Our study suggests that among the possible four initiation sites in EGP only the hydroxyl group on carbon C-6 took part in the initiation process.

Keywords

Lipase Ethyl glucopyranoside ε-Caprolactone Ring-opening polymerization Two-dimensional NMR Regioselectivity Multifunctional initiator Site of reaction Caprolactone Glucopyranoside

Get full access to this article

View all access options for this article.

References

Malm

C. J.

Meneh

J. W.

Kendall

D. L.

and Hiatt

G. D

, Ind. Eng. Chem. 43, 684 (1951).

Martin

B. D.

Ampofo

S. A.

Linhardt

R. J.

and Dordick

J. S

, Macromolecules 25, 7081 (1992).

Ikeda

and Klibanov

A. M

, Biotechnol. Bioeng. 42, 788 (1993).

Sugihara

J. M.

, Adv. Carbohydr. Chem. Biochem. 8, 1 (1953).

Haines

A. H.

, Adv. Carbohydr. Chem. Biochem. 33, 11 (1976).

Wolfrom

M. L.

and Szarek

W. A

, in The Carbohydrates Chemistry and Biochemistry, Pigman

and Horton

, Eds. (Academic Press, New York, 1972), 2nd ed., Vol. IA, pp. 217–251.

Haines

A. H.

, Adv. Carbohydr. Chem. Biochem. 39, 13 (1981).

Therisod

and Klibanov

A. M

, J. Am. Chem. Soc. 108, 5638 (1986).

Sweers

H. M.

and Wong

C. H

, J. Am. Chem. Soc. 108, 6421 (1986).

10.

Klibanov

A. M.

, Biotechnol. Bioeng. 29, 648 (1987).

11.

Therisod

and Klibanov

A. M

, J. Am. Chem. Soc. 109, 3977 (1987).

12.

Kloosterman

Mosmuller

E. W. J.

Schoemaker

H. E.

and Meijer

E. M

, Tetrahedron Lett. 28, 2989 (1987).

13.

Chopineau

McCafferty

F. D.

Therisod

and Klibanov

A. M

, Biotechnol. Bioeng. 31, 208 (1988).

14.

Riva

Chopineau

Kieboom

A. P. G.

and Klibanov

A. M

, J. Am. Chem. Soc. 110, 584 (1988).

15.

Carrea

Riva

Secundo

and Danieli

, J. Chem. Soc., Chem. Commun. 1057 (1989).

16.

Shaw

J. F.

Gotor

and Pulido

R. J

, J. Chem. Soc., Perkin Trans. 1 491 (1991).

17.

Prasad

A. K.

Sorensen

M. D.

Parmar

V. S.

and Wengel

, Tetrahedron Lett. 36, 6163 (1995).

18.

Klibanov

A. M.

, CHEMTECH 16, 354 (1986).

19.

Seino

Uchibori

Nishitani

and Inmasu

, J. Am. Oil. Chem. Soc. 61, 1761 (1984).

20.

Bjorkling

Godfredsen

S. E.

and Kirk

, J. Chem. Soc., Chem. Commun. 934 (1989).

21.

Adelhorst

Bjorkling

Godfredsen

S. E.

and Kirk

, Synthesis 112 (1990).

22.

Bisht

K. S.

Deng

Gross

R. A.

Kaplan

D. L.

and Swift

, J. Am. Chem. Soc. 120, 1363 (1998).

23.

Aue

W. P.

Bartholdi

and Ernst

R. R

, J. Chem. Phys. 64, 2229 (1976).

24.

MacDonald

R. T.

Pulapura

S. K.

Svirkin

Y. Y.

Gross

R. A.

Kaplan

D. L.

Akkara

J. A.

Swift

and Wolk

, Macromolecules 20, 73 (1995).

25.

Bisht

K. S.

Sivirkin

Y. Y.

Henderson

L. A.

Gross

R. A.

Kaplan

D. L.

and Swift

, Macromolecules 30, 7735 (1997).

26.

Bisht

K. S.

Henderson

L. A.

Gross

R. A.

Kaplan

D. L.

and Swift

, Macromolecules 29, 7759 (1996).

27.

Uyama

and Kobayashi

, Chem. Lett. 1149 (1993).

28.

Doddrell

D. M.

Pegg

D. T.

and Bendall

M. R

, J. Magn. Reson. 48, 323 (1982).

29.

Breitmaier

and Bauer

, 13C NMR Spectroscopy: A Working Manual with Exercises (Harwood Academic Publisher, New York, 1984), pp. 54–57.

Enzymatic Polymerization of Poly(ε-CL) Containing an Ethyl Glucopyranoside Head Group: An NMR Study

Abstract

Keywords

Get full access to this article

References