Total synthesis of woodrosin I - Part 1: Preparation of the building blocks and evaluation of the glycosylation strategy

Chemistry - A European Journal

Volumn 9, Issue 1, 2003, Pages 307-319

  Fürstner, Alois ^a   Jeanjean, Fabien ^a   Razon, Patrick ^a   Wirtz, Conny ^a   Mynott, Richard ^a  

^a MAX PLANCK INSTITUT FÜR KOHLENFORSCHUNG   (Germany)

Author keywords

Carbohydrates; Glycolipids; Glycosides; Macrolides; Natural products

Indexed keywords

CATALYSIS; SUGARS; TITANIUM;

GLYCOSYLATION;

SYNTHESIS (CHEMICAL);

5 HEXANAL; ALCOHOL DERIVATIVE; DISACCHARIDE; GLUCOSE; GLUCOSIDE; GLYCOSIDE; OLIGOSACCHARIDE; PENTASACCHARIDE; RHAMNOSE; TITANIUM; TRICHLOROACETIMIDIC ACID; UNCLASSIFIED DRUG; WOODROSIN I; ZINC DERIVATIVE;

ARTICLE; BIOCHEMISTRY; CARBOHYDRATE ANALYSIS; CATALYSIS; CHEMICAL MODIFICATION; CHEMICAL REACTION; CHEMISTRY; DRUG STRUCTURE; DRUG SYNTHESIS; ENANTIOSELECTIVITY; GLYCOSYLATION; METABOLISM; METHODOLOGY; MODEL; MOLECULAR GENETICS; REACTION ANALYSIS; STRUCTURE ANALYSIS; SYNTHESIS;

BIOCHEMISTRY; CARBOHYDRATE SEQUENCE; GLUCOSIDES; GLYCOSYLATION; MOLECULAR SEQUENCE DATA; OLIGOSACCHARIDES; RHAMNOSE;

EID: 0037415091     PISSN: 09476539     EISSN: None     Source Type: Journal    
DOI: 10.1002/chem.200390025     Document Type: Article

References (125)

1. a) J. F. W. Johnston, Philos. Trans. R. Soc. London 1840, 130, 341-360;
2. b) G. A. Kayser, Justus Liebigs Ann. Chem. 1844. 51, 81-105;
3. c) W. Mayer, Justus Liebigs Ann. Chem. 1855, 95, 129-176;
4. d) F. B. Power, H. Rogerson, J. Chem. Soc. Trans. 1912, 101, 1-26;
5. e) C. Mannich, P. Schumann, Arch. Pharm. Ber. Dtsch. Pharm. Ges. 1938, 276, 211-226.
6. Tricolorin family: a) R. Pereda-Miranda, R. Mata, A. L. Anaya, D. B. M. Wickramaratne, J. M. Pezzuto, A. D. Kinghorn, J. Nat. Prod. 1993, 56, 571-582; b) M. Bah, R. Pereda-Miranda, Tetrahedron 1996, 52, 13 063-13 080; c) M. Bah, R. Pereda-Miranda, Tetrahedron 1997, 53, 9007-9022.
7. Tricolorin family: a) R. Pereda-Miranda, R. Mata, A. L. Anaya, D. B. M. Wickramaratne, J. M. Pezzuto, A. D. Kinghorn, J. Nat. Prod. 1993, 56, 571-582; b) M. Bah, R. Pereda-Miranda, Tetrahedron 1996, 52, 13 063-13 080; c) M. Bah, R. Pereda-Miranda, Tetrahedron 1997, 53, 9007-9022.
8. Tricolorin family: a) R. Pereda-Miranda, R. Mata, A. L. Anaya, D. B. M. Wickramaratne, J. M. Pezzuto, A. D. Kinghorn, J. Nat. Prod. 1993, 56, 571-582; b) M. Bah, R. Pereda-Miranda, Tetrahedron 1996, 52, 13 063-13 080; c) M. Bah, R. Pereda-Miranda, Tetrahedron 1997, 53, 9007-9022.
9. Simonins: N. Noda, S. Yoda, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1992, 40, 3163-3168.
10. Orizabins: a) N. Noda, M. Ono, K. Miyahara, T. Kawasaki, M. Okabe, Tetrahedron 1987, 43, 3889-3902; b) B. Hernández-Carlos, R. Bye, R. Pereda-Miranda, J. Nat. Prod. 1999, 62, 1096-1100.
11. Orizabins: a) N. Noda, M. Ono, K. Miyahara, T. Kawasaki, M. Okabe, Tetrahedron 1987, 43, 3889-3902; b) B. Hernández-Carlos, R. Bye, R. Pereda-Miranda, J. Nat. Prod. 1999, 62, 1096-1100.
12. Multifidins: M. Ono, F. Honda, A. Karahashi, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1997, 45, 1955-1960.
13. Stoloniferins: a) N. Noda, N. Takahashi, K. Miyahara, C.-R. Yang, Phytochemistry 1998, 48, 837-841; b) N. Noda, N. Takahashi, T. Kawasaki, K. Miyahara, C.-R. Yang, Phytochemistry 1994, 36, 365-371.
14. Stoloniferins: a) N. Noda, N. Takahashi, K. Miyahara, C.-R. Yang, Phytochemistry 1998, 48, 837-841; b) N. Noda, N. Takahashi, T. Kawasaki, K. Miyahara, C.-R. Yang, Phytochemistry 1994, 36, 365-371.
15. Operculins: a) M. Ono, M. Nishi, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1990, 38, 2986-2991; b) M. Ono, T. Fukunaga, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1990, 38, 2650-2655; c) M. Ono, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1989, 37, 3209-3213.
16. Operculins: a) M. Ono, M. Nishi, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1990, 38, 2986-2991; b) M. Ono, T. Fukunaga, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1990, 38, 2650-2655; c) M. Ono, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1989, 37, 3209-3213.
17. Operculins: a) M. Ono, M. Nishi, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1990, 38, 2986-2991; b) M. Ono, T. Fukunaga, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1990, 38, 2650-2655; c) M. Ono, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1989, 37, 3209-3213.
18. Tuguajalapins: N. Noda, K. Tsuji, K. Miyahara, C.-R. Yang, Chem. Pharm. Bull. 1994, 42, 2011-2016.
19. Mammosides: a) I. Kitagawa, K. Ohashi, N. I. Baek, M. Sakagami, M. Yoshikawa, H. Shibuya, Chem. Pharm. Bull. 1997, 45, 786-794; b) I. Kitagawa, N. I. Baek, K. Ohashi, M. Sakagami, M. Yoshikawa, H. Shibuya, Chem. Pharm. Bull. 1989, 37, 1131-1133.
20. Mammosides: a) I. Kitagawa, K. Ohashi, N. I. Baek, M. Sakagami, M. Yoshikawa, H. Shibuya, Chem. Pharm. Bull. 1997, 45, 786-794; b) I. Kitagawa, N. I. Baek, K. Ohashi, M. Sakagami, M. Yoshikawa, H. Shibuya, Chem. Pharm. Bull. 1989, 37, 1131-1133.
21. Quamoclins: M. Ono, K. Kuwabata, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1992, 40, 2674-2680.
22. Soldanelline: a) E. M. M. Gaspar, Eur. J. Org. Chem. 2001, 369-373; b) E. M. M. Gaspar, Tetrahedron Lett. 1999, 40, 6861-6864.
23. Soldanelline: a) E. M. M. Gaspar, Eur. J. Org. Chem. 2001, 369-373; b) E. M. M. Gaspar, Tetrahedron Lett. 1999, 40, 6861-6864.
24. a) W. F. Reynolds, M. Yu, R. G. Enriquez, H. Gonzalez, I. Leon, G. Magos, M. L. Villareal, J. Nat. Prod. 1995, 58, 1730-1734;
25. b) R. G. Enriquez, I. Leon, F. Perez, F. Walls, K. A. Carpenter, F. V. Puzzuoli, W. F. Reynolds, Can. J. Chem. 1992, 70, 1000-1008.
26. See the following for leading references on further families of resin glycosides: a) J. K. MacLeod, A. Ward, P. B. Oelrichs, J. Nat. Prod. 1997, 60, 467-471; b) I. Kitagawa, N. I. Baek, K. Kawashima, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1680-1692; c) N. Noda, K. Tsuji, T. Kawasaki, K. Miyahara, H. Hanazono, C.-R. Yang, Chem. Pharm. Bull. 1995, 43, 1061-1063; d) N. Noda, H. Kobayashi, K. Miyahara, T. Kawasaki, Chem. Pharm. Bull. 1988, 36, 920-929; e) I. Kitagawa, N. I. Baek, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1693-1699; f) Y. Fang, W. Chai, S. Chen, Y. He, L. Zhao, J. Peng, H. Huang, B. Xin, Carbohydr. Res. 1993, 245, 259-270.
27. See the following for leading references on further families of resin glycosides: a) J. K. MacLeod, A. Ward, P. B. Oelrichs, J. Nat. Prod. 1997, 60, 467-471; b) I. Kitagawa, N. I. Baek, K. Kawashima, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1680-1692; c) N. Noda, K. Tsuji, T. Kawasaki, K. Miyahara, H. Hanazono, C.-R. Yang, Chem. Pharm. Bull. 1995, 43, 1061-1063; d) N. Noda, H. Kobayashi, K. Miyahara, T. Kawasaki, Chem. Pharm. Bull. 1988, 36, 920-929; e) I. Kitagawa, N. I. Baek, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1693-1699; f) Y. Fang, W. Chai, S. Chen, Y. He, L. Zhao, J. Peng, H. Huang, B. Xin, Carbohydr. Res. 1993, 245, 259-270.
28. See the following for leading references on further families of resin glycosides: a) J. K. MacLeod, A. Ward, P. B. Oelrichs, J. Nat. Prod. 1997, 60, 467-471; b) I. Kitagawa, N. I. Baek, K. Kawashima, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1680-1692; c) N. Noda, K. Tsuji, T. Kawasaki, K. Miyahara, H. Hanazono, C.-R. Yang, Chem. Pharm. Bull. 1995, 43, 1061-1063; d) N. Noda, H. Kobayashi, K. Miyahara, T. Kawasaki, Chem. Pharm. Bull. 1988, 36, 920-929; e) I. Kitagawa, N. I. Baek, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1693-1699; f) Y. Fang, W. Chai, S. Chen, Y. He, L. Zhao, J. Peng, H. Huang, B. Xin, Carbohydr. Res. 1993, 245, 259-270.
29. See the following for leading references on further families of resin glycosides: a) J. K. MacLeod, A. Ward, P. B. Oelrichs, J. Nat. Prod. 1997, 60, 467-471; b) I. Kitagawa, N. I. Baek, K. Kawashima, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1680-1692; c) N. Noda, K. Tsuji, T. Kawasaki, K. Miyahara, H. Hanazono, C.-R. Yang, Chem. Pharm. Bull. 1995, 43, 1061-1063; d) N. Noda, H. Kobayashi, K. Miyahara, T. Kawasaki, Chem. Pharm. Bull. 1988, 36, 920-929; e) I. Kitagawa, N. I. Baek, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1693-1699; f) Y. Fang, W. Chai, S. Chen, Y. He, L. Zhao, J. Peng, H. Huang, B. Xin, Carbohydr. Res. 1993, 245, 259-270.
30. See the following for leading references on further families of resin glycosides: a) J. K. MacLeod, A. Ward, P. B. Oelrichs, J. Nat. Prod. 1997, 60, 467-471; b) I. Kitagawa, N. I. Baek, K. Kawashima, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1680-1692; c) N. Noda, K. Tsuji, T. Kawasaki, K. Miyahara, H. Hanazono, C.-R. Yang, Chem. Pharm. Bull. 1995, 43, 1061-1063; d) N. Noda, H. Kobayashi, K. Miyahara, T. Kawasaki, Chem. Pharm. Bull. 1988, 36, 920-929; e) I. Kitagawa, N. I. Baek, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1693-1699; f) Y. Fang, W. Chai, S. Chen, Y. He, L. Zhao, J. Peng, H. Huang, B. Xin, Carbohydr. Res. 1993, 245, 259-270.
31. See the following for leading references on further families of resin glycosides: a) J. K. MacLeod, A. Ward, P. B. Oelrichs, J. Nat. Prod. 1997, 60, 467-471; b) I. Kitagawa, N. I. Baek, K. Kawashima, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1680-1692; c) N. Noda, K. Tsuji, T. Kawasaki, K. Miyahara, H. Hanazono, C.-R. Yang, Chem. Pharm. Bull. 1995, 43, 1061-1063; d) N. Noda, H. Kobayashi, K. Miyahara, T. Kawasaki, Chem. Pharm. Bull. 1988, 36, 920-929; e) I. Kitagawa, N. I. Baek, Y. Yokokawa, M. Yoshikawa, K. Ohashi, H. Shibuya, Chem. Pharm. Bull. 1996, 44, 1693-1699; f) Y. Fang, W. Chai, S. Chen, Y. He, L. Zhao, J. Peng, H. Huang, B. Xin, Carbohydr. Res. 1993, 245, 259-270.
32. Short review of the early work: H. Wagner, Nobel Symp. 1974, 25, 235-240.
33. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
34. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
35. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
36. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
37. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
38. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
39. Although most resin glycosides have been isolated from plants (Convolvulaceae), scattered reports on the isolation of related glycolipids from bacteria, fungi and yeasts can be found in the literature, some of which contain fatty acid components other than jalapinolic acid as the aglycon. For an extensive compilation of relevant literature on the isolation, structure and biological properties of such glycolipids see the following for leading references: a) K. S. Bisht, R. A. Gross, D. L. Kaplan, J. Org. Chem. 1999, 64, 780-789; b) see also: G. Legler, Phytochemistry 1965, 4, 29-41; c) H. Wagner, P. Kazmaier, Tetrahedron Lett. 1971, 12, 3233-3236; d) T. Kawasaki, H. Okabe, I. Nakatsuka, Chem. Pharm. Bull. 1971, 19, 1144-1149 and references therein; e) T. Hirayama, I. Kato, FEBS Lett. 1982, 139, 81-85; f) L. Weber, J. Stach, G. Haufe, R. Hommel, H. P. Kleber, Carbohydr. Res. 1990, 206, 13-19; g) H. J. Asmer, S. Lang, F. Wagner, V. Wray, J. Am. Oil Chem. Soc. 1988, 65, 1460-1466.
40. Z.-H. Jiang, A. Geyer, R. R. Schmidt, Angew. Chem. 1995, 107, 2730-2734; Angew. Chem. Int. Ed. Engl. 1995, 34, 2520-2524.
41. Z.-H. Jiang, A. Geyer, R. R. Schmidt, Angew. Chem. 1995, 107, 2730-2734; Angew. Chem. Int. Ed. Engl. 1995, 34, 2520-2524.
42. J. Furukawa, S. Kobayashi, M. Nomizu, N. Nishi, N. Sakairi, Tetrahedron Lett. 2000, 41, 3453-3457.
43. For the synthesis of a related resin glycoside isolated from a yeast see: A. Fürstner, K. Radkowski, J. Grabowski, C. Wirtz, R. Mynott, J. Org. Chem. 2000, 65, 8758-8762.
44. For a short review see: J. Furukawa, N. Sakairi, Trends Glycosci. Glycotechnol. 2001, 13, 1-10.
45. a) D. P. Larson, C. H. Heathcock, J. Org. Chem. 1996, 61, 5208-5209;
46. b) D. P. Larson, C. H. Heathcock, J. Org. Chem. 1997, 62, 8406-8418.
47. a) S.-F. Lu, Q. O'yang, Z.-W. Guo, B. Yu, Y.-Z. Hui, Angew. Chem. 1997, 109, 2442-2444; Angew. Chem. Int. Ed. Engl. 1997, 36, 2344-2346;
48. a) S.-F. Lu, Q. O'yang, Z.-W. Guo, B. Yu, Y.-Z. Hui, Angew. Chem. 1997, 109, 2442-2444; Angew. Chem. Int. Ed. Engl. 1997, 36, 2344-2346;
49. b) S.-F. Lu, Q. O'yang, Z.-W. Guo, B. Yu, Y.-Z. Hui, J. Org. Chem. 1997, 62, 8400-8405.
50. a) A. Fürstner, T. Müller, J. Am. Chem. Soc. 1999, 121, 7814-7821;
51. b) A. Fürstner, T. Müller, J. Org. Chem. 1998, 63, 424-425;
52. c) C. W. Lehmann, A. Fürstner, T. Müller, Z. Kristallogr. 2000, 215, 114-117.
53. M. Ono, K. Nakagawa, T. Kawasaki, K. Miyahara, Chem. Pharm. Bull. 1993, 41, 1925-1932.
54. For a preliminary communication see: A. Fürstner, F. Jeanjean, P. Razon, Angew. Chem. 2002, 114, 2203-2206; Angew. Chem. Int. Ed. 2002, 41, 2097-2101.
55. For a preliminary communication see: A. Fürstner, F. Jeanjean, P. Razon, Angew. Chem. 2002, 114, 2203-2206; Angew. Chem. Int. Ed. 2002, 41, 2097-2101.
56. A. Fürstner, F. Jeanjean, P. Razon, C. Wirtz, R. Mynott, Chem. Eur. J. 2003, 9, 320-326 following paper.
57. For another recent study on a complex glycolipid from this laboratory see: a) A. Fürstner, M. Albert, J. Mlynarski, M. Matheu, J. Am. Chem. Soc. 2002, 124, 1168-1169; b) A. Fürstner, J. Mlynarski, M. Albert, J. Am. Chem. Soc. 2002, 124, 10274-10275.
58. For another recent study on a complex glycolipid from this laboratory see: a) A. Fürstner, M. Albert, J. Mlynarski, M. Matheu, J. Am. Chem. Soc. 2002, 124, 1168-1169; b) A. Fürstner, J. Mlynarski, M. Albert, J. Am. Chem. Soc. 2002, 124, 10274-10275.
59. a) T. M. Trnka, R. H. Grubbs, Acc. Chem. Res. 2001, 34, 18-29;
60. b) A. Fürstner, Angew. Chem. 2000, 112, 3140-3172; Angew. Chem. Int. Ed. 2000, 39, 3012-3043;
61. b) A. Fürstner, Angew. Chem. 2000, 112, 3140-3172; Angew. Chem. Int. Ed. 2000, 39, 3012-3043;
62. c) R. H. Grubbs, S. Chang, Tetrahedron 1998, 54, 4413-4450;
63. d) M. Schuster, S. Blechert, Angew. Chem. 1997, 109, 2124-2144; Angew. Chem. Int. Ed. Engl. 1997, 36, 2037-2056;
64. d) M. Schuster, S. Blechert, Angew. Chem. 1997, 109, 2124-2144; Angew. Chem. Int. Ed. Engl. 1997, 36, 2037-2056;
65. e) A. Fürstner, Top. Catal. 1997, 4, 285-299;
66. f) S. K. Armstrong, J. Chem. Soc. Perkin Trans. 1 1998, 371-388.
67. A. Fürstner, O. R. Thiel, C. W. Lehmann, Organometallics 2002, 21, 331-335.
68. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
69. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
70. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
71. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
72. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
73. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
74. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
75. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
76. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
77. The effect of chelating substituents on the efficiency of RCM has been amply demonstrated by our group, cf.: a) A. Fürstner, K. Langemann, J. Org. Chem. 1996, 61, 3942-3943; b) A. Fürstner, K. Langemann, Synthesis 1997, 792-803; c) A. Fürstner, T. Gastner, H. Weintritt, J. Org. Chem. 1999, 64, 2361-2366; d) A. Fürstner, J. Grabowski, C. W. Lehmann, J. Org. Chem. 1999, 64, 8275-8280; e) A. Fürstner, G. Seidel, N. Kindler, Tetrahedron 1999, 55, 8215-8230; f) A. Fürstner, K. Langemann, J. Am. Chem. Soc. 1997, 119, 9130-9136; g) A. Fürstner, O. R. Thiel, N. Kindler, B. Bartkowska, J. Org. Chem. 2000, 65, 7990-7995; h) A. Fürstner, T. Dierkes, O. R. Thiel, G. Blanda, Chem. Eur. J. 2001, 7, 5286-5298; i) A. Fürstner, K. Radkowski, C. Wirtz, R. Goddard, C. W. Lehmann, R. Mynott, J. Am. Chem. Soc. 2002, 124, 7061-7069; j) A. Fürstner, Top. Organomet. Chem. 1998, 1, 37-72.
78. a) H. Paulsen, Angew. Chem. 1982, 94, 184-201; Angew. Chem. Int. Ed. Engl. 1982, 21, 155-173;
79. a) H. Paulsen, Angew. Chem. 1982, 94, 184-201; Angew. Chem. Int. Ed. Engl. 1982, 21, 155-173;
80. b) R. R. Schmidt, in Comprehensive Organic Synthesis, Vol. 6 (Eds.: B. M. Trost, I. Fleming), Pergamon, Oxford, 1991, pp. 33-61;
81. c) K. Toshima, K. Tatsuta, Chem. Rev. 1993, 93, 1503-1531.
82. T. W. Greene, P. G. M. Wuts, Protective Groups in Organic Synthesis, 3rd ed., Wiley, New York, 1999.
83. a) R. R. Schmidt, Angew. Chem. 1986, 98, 213-236; Angew. Chem. Int. Ed. Engl. 1986, 25, 212-235;
84. a) R. R. Schmidt, Angew. Chem. 1986, 98, 213-236; Angew. Chem. Int. Ed. Engl. 1986, 25, 212-235;
85. b) R. R. Schmidt, W. Kinzy, Adv. Carbohydr. Chem. Biochem. 1994, 50, 21-123;
86. c) R. R. Schmidt, K.-H. Jung, in Preparative Carbohydrate Chemistry (Ed.: S. Hanessian), Dekker, New York, 1997, pp. 283-312.
87. a) A. Fürstner, I. Konetzki, J. Org. Chem. 1998, 63, 3072-3080;
88. b) A. Fürstner, I. Konetzki, Tetrahedron 1996, 52, 15071-15078.
89. a) R. U. Lemieux, A. R. Morgan, Can. J. Chem. 1965, 43, 2199-2201;
90. b) M. A. E. Shaban, R. W. Jeanloz, Carbohydr. Res. 1976, 52, 103-114;
91. c) F. W. Lichtenthaler, T. Schneider-Adams, J. Org. Chem. 1994, 59, 6728-6734.
92. A. Fürstner, I. Konetzki, Tetrahedron Lett. 1998, 39, 5721-5724.
93. a) A. B. Charette, J.-F. Marcoux, B. Côté, Tetrahedron Lett. 1991, 32, 7215-7218;
94. b) W. J. Sanders, D. D. Manning, K. M. Koeller, L. L. Kiessling, Tetrahedron 1997, 53, 16391-16422.
95. a) G. Excoffier, D. Gagnaire, J.-P. Utille, Carbohydr. Res. 1975, 39, 368-373;
96. b) A. Lubineau, E. Meyer, P. Place, Carbohydr. Res. 1992, 228, 191-203;
97. c) U. E. Udodong, C. S. Rao, B. Fraser-Reid, Tetrahedron 1992, 48, 4713-4724;
98. d) J. R. Marino-Abernas, R. Bittman, A. Peters, E. Mayhew, J. Med. Chem. 1996, 39, 3241-3247.
99. P. L. Barili, G. Berti, G. Catelani, C. Cini, F. D'Andrea, E. Mastrorilli, Carbohydr. Res. 1995, 278, 43-57.
100. a) H. Takahashi, T. Kawakita, M. Ohno, M. Yoshioka, S. Kobayashi, Tetrahedron 1992, 48, 5691-5700;
101. b) P. Knochel, in Active Metals: Preparation, Characterization, Applications (Ed.: A. Fürstner), VCH, Weinheim, 1996, pp. 191-236;
102. c) P. Knochel, Synlett 1995, 393-403;
103. d) R. Noyori, Asymmetric Catalysis in Organic Synthesis, Wiley, New York, 1994, p. 255-297.
104. J. Zhang, J. Mao, H. Chen, M. Cai, Tetrahedron: Asymmetry 1994, 5, 2283-2290.
105. S. David, in Preparative Carbohydrate Chemistry (Ed.: S. Hanessian), Dekker, New York, 1997, pp. 69-86.
106. 2/HgO.
107. S. J. Danishefsky, M.T. Bilodeau, Angew. Chem. 1996, 108, 1483-1522; Angew. Chem. Int. Ed. Engl. 1996, 35, 1380-1419.
108. S. J. Danishefsky, M.T. Bilodeau, Angew. Chem. 1996, 108, 1483-1522; Angew. Chem. Int. Ed. Engl. 1996, 35, 1380-1419.
109. K. C. Nicolaou, H. J. Mitchell, N. F. Jain, T. Bando, R. Hughes, N. Winssinger, S. Natarajan, A. E. Koumbis, Chem. Eur. J. 1999, 5, 2648-2667.
110. K. Ruda, J. Lindberg, P. J. Garegg, S. Oscarson, P. Konradsson, J. Am. Chem. Soc. 2000, 122, 11067-11072.
111. This reaction must be quenched after 10 min; if the reaction mixture is kept for longer times, partial cleavage of the second chloroacetyl group at O-2 is observed.
112. While the desired product 40 is only poorly soluble in MeOH, the regioisomer 39 bearing the -OPMB group at the 2′-position is readily dissolved in this medium. Crude 40 thus formed is further purified by recrystallization from MeCN, cf. Experimental Section.
113. 2O alone; therefore some THF has to be added to the reaction mixture.
114. Y. Oikawa, T. Yoshioka, O. Yonemitsu, Tetrahedron Lett. 1982, 23, 885-888.
115. For regioselective reactions of acetimidate donors with diols see: a) P. Zimmermann, U. Greilich, R. R. Schmidt, Tetrahedron Lett. 1990, 31, 1849-1852; b) S. Canevari, D. Colombo, F. Compostella, L. Panza, F. Ronchetti, G. Russo, L. Toma, Tetrahedron 1999, 55, 1469-1478.
116. For regioselective reactions of acetimidate donors with diols see: a) P. Zimmermann, U. Greilich, R. R. Schmidt, Tetrahedron Lett. 1990, 31, 1849-1852; b) S. Canevari, D. Colombo, F. Compostella, L. Panza, F. Ronchetti, G. Russo, L. Toma, Tetrahedron 1999, 55, 1469-1478.
117. For regioselective reactions of other glycosyl donors with diols see: a) V. Verez-Bencomo, M. T. Campos-Valdes, J. R. Marino-Albernas, V. Fernandez-Santana, M. Hernandez-Rensoli, C. S. Perez-Martinez, Carbohydr. Res. 1991, 217, 263-267; b) K. Oshima, Y. Aoyama, J. Am. Chem. Soc. 1999, 121, 2315-2316; c) H. Baumann, P. E. Jansson, L. Kenne, J. Chem. Soc. Perkin Trans. 1 1988, 209-217; d) R. J. Tennant-Eyles, B. G. Davis, A. Fairbanks, Chem. Commun. 1999, 1037-1038.
118. For regioselective reactions of other glycosyl donors with diols see: a) V. Verez-Bencomo, M. T. Campos-Valdes, J. R. Marino-Albernas, V. Fernandez-Santana, M. Hernandez-Rensoli, C. S. Perez-Martinez, Carbohydr. Res. 1991, 217, 263-267; b) K. Oshima, Y. Aoyama, J. Am. Chem. Soc. 1999, 121, 2315-2316; c) H. Baumann, P. E. Jansson, L. Kenne, J. Chem. Soc. Perkin Trans. 1 1988, 209-217; d) R. J. Tennant-Eyles, B. G. Davis, A. Fairbanks, Chem. Commun. 1999, 1037-1038.
119. For regioselective reactions of other glycosyl donors with diols see: a) V. Verez-Bencomo, M. T. Campos-Valdes, J. R. Marino-Albernas, V. Fernandez-Santana, M. Hernandez-Rensoli, C. S. Perez-Martinez, Carbohydr. Res. 1991, 217, 263-267; b) K. Oshima, Y. Aoyama, J. Am. Chem. Soc. 1999, 121, 2315-2316; c) H. Baumann, P. E. Jansson, L. Kenne, J. Chem. Soc. Perkin Trans. 1 1988, 209-217; d) R. J. Tennant-Eyles, B. G. Davis, A. Fairbanks, Chem. Commun. 1999, 1037-1038.
120. For regioselective reactions of other glycosyl donors with diols see: a) V. Verez-Bencomo, M. T. Campos-Valdes, J. R. Marino-Albernas, V. Fernandez-Santana, M. Hernandez-Rensoli, C. S. Perez-Martinez, Carbohydr. Res. 1991, 217, 263-267; b) K. Oshima, Y. Aoyama, J. Am. Chem. Soc. 1999, 121, 2315-2316; c) H. Baumann, P. E. Jansson, L. Kenne, J. Chem. Soc. Perkin Trans. 1 1988, 209-217; d) R. J. Tennant-Eyles, B. G. Davis, A. Fairbanks, Chem. Commun. 1999, 1037-1038.
121. J. R. Marino-Albernas, R. Bittman, A. Peters, E. Mayhew, J. Med. Chem. 1996, 39, 3241-3247.
122. a) D. Crich, L. B. L. Lim, J. Chem. Soc. Perkin Trans. 1 1991, 2209-2214;
123. b) M. Trumtel, P. Tavecchia, A. Veyrières, P. Sinay Carbohydr. Res. 1989, 191, 29-52;
124. c) P. Boullanger, J. C. Martin, G. Descotes, J. Heterocycl. Chem. 1975, 12, 91-93.
125. R. R. Schmidt, G. Effenberger, Liebigs Ann. Chem. 1987, 825-831.