Stable axial-rich conformation of pyranoses derived from L-rhamnose and D-mannose

Tetrahedron Letters

Volumn 40, Issue 30, 1999, Pages 5573-5576

  Yamada, Hidetoshi ^a   Nakatani, Mari ^a   Ikeda, Tomonari ^a   Marumoto, Yuzo ^a  

^a KWANSEI GAKUIN UNIVERSITY   (Japan)

Author keywords

Carbohydrates; Conformation

Indexed keywords

CARBOHYDRATE; HYDROXYL GROUP; MANNOSE; RHAMNOSE;

ARTICLE; CHEMICAL REACTION; CHEMICAL STRUCTURE; NUCLEAR MAGNETIC RESONANCE; STEREOSPECIFICITY;

EID: 0033166819     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(99)01077-1     Document Type: Article

References (12)

1. Lemieux, R. U.; Morgan, A. R. Can. J. Chem. 1965, 43, 2205-2213.
2. In this paper, following abbreviations are used; MPM: p-methoxyphenylmethyl, TBS: tert-butyldimethylsilyl, TES: triethylsilyl, TPS: tert-butyldiphenylsilyl. Others complied with a standard list of abbreviations (J. Org. Chem. 1999, 64, 21A).
3. Tius, M. A.; Bush-Petersen, J. Tetrahedron Lett. 1994, 35, 5181-5184. Hosoya, T.; Ohashi, Y.; Matsumoto, T.; Suzuki, K.Tetrahedron Lett. 1996, 37, 663-666.
4. Tius, M. A.; Bush-Petersen, J. Tetrahedron Lett. 1994, 35, 5181-5184. Hosoya, T.; Ohashi, Y.; Matsumoto, T.; Suzuki, K. Tetrahedron Lett. 1996, 37, 663-666.
5. Kiss, J.; Arnold, W. Helv. Chim. Acta 1975, 58, 297-301.
6. 6 respectively. The observation suggests the existence of plural conformers that have subtle conformational differences around C3 and C4. At 60 °C all signals were averaged to be sharp.
7. Westerduin, P.; De Haan, P. E.; Dees, M. J.; Van Boom, J. H. Carbohydr. Res. 1988, 180, 195-205.
8. The β-isomers were prepared along with corresponding α-isomers. The glycosylation will be described in detail elsewhere.
9. 2 (3 equiv), TsOH (0.1 equiv), DMF, 45 °C, 10 mmHg, 2 h, 74%] followed by tert-butyldiphenylsilylation [TPSCl (2.5 equiv), imidazole (2.6 equiv), 4-DMAP (0.5 equiv), DMF, 100 °C, 8 h, 62%].
10. C4 conformation.
11. 3; Mo, Kα radiation; θmax = 26.43°; 4908 reflections collected, of which 3998 were used in the solution of the structure; R index = 0.072; diffractometer Mac Science MXC18. Atomic coordinates, bond lengths and angles and thermal parameters are deposited in the Cambridge Crystallographic Data Centre.
12. 3) δ -0.21 (3, s), -0.04 (3, s), 0.79 (9, s), 1.08 (9, s), 3.26 (1, dd, 12.0, 3.6; H6), 3.71 (1, dd, 4.9, 2.4; H4), 3.85 (1, dd, 12.0, 8.5; H6), 3.87 (1, dd, 6.8, 2.9; H2), 3.99 (1, ddd, 8.5, 4.9, 3.6; H5), 4.03 (1, dd, 2.9, 2.4; H3), 5.06 (1, d, 6.8; H1), 7.36-7.46 (6, m), 7.63-7.69 (4, H).