One‐Pot Synthesis of Sialo‐Containing Glycosyl Amino Acids by Use of an <i>N</i>‐Trichloroethoxycarbonyl‐β‐thiophenyl Sialoside
書誌事項
- 公開日
- 2005-01-18
- 権利情報
-
- http://onlinelibrary.wiley.com/termsAndConditions#vor
- DOI
-
- 10.1002/chem.200400840
- 公開者
- Wiley
この論文をさがす
説明
<jats:title>Abstract</jats:title><jats:p>We describe an efficient synthesis of 2,6‐ and 2,3‐sialyl T antigens linked to serine in a one‐pot glycosylation. We first investigated the glycosidation of thiosialosides by varying the <jats:italic>N</jats:italic>‐protecting group. Modification of the C‐5 amino group of β‐thiosialosides into the <jats:italic>N</jats:italic>‐9‐fluorenylmethoxycarbonyl, <jats:italic>N</jats:italic>‐2,2,2‐trichloroethoxycarbonyl (<jats:italic>N</jats:italic>‐Troc), and <jats:italic>N</jats:italic>‐trichloroacetyl derivatives enhanced the reactivity of these compounds towards glycosidation. Addition of a minimum amount of 3 Å molecular sieves was also effective in improving the yield of α‐linked sialosides. Next, we conducted one‐pot syntheses of the glycosyl amino acids by using the <jats:italic>N</jats:italic>‐Troc sialyl donor. The <jats:italic>N</jats:italic>‐Troc derivative can be converted into the <jats:italic>N</jats:italic>‐acetyl derivative without racemization of the amino acids. Branched‐type one‐pot glycosylation, initiated by regioselective glycosylation of the 3,6‐dihydroxy galactoside with the <jats:italic>N</jats:italic>‐Troc‐β‐thiophenyl sialoside, provided the protected 2,6‐sialyl T antigen in good yield. Linear‐type one‐pot glycosylation, initiated by chemoselective glycosylation of galactosyl fluoride with the <jats:italic>N</jats:italic>‐Troc‐β‐thiophenyl sialoside, afforded the protected 2,3‐sialyl T antigen in excellent yield. Both protected glycosyl amino acids were converted into the fully deprotected 2,6‐ and 2,3‐sialyl T antigens linked to serine in good yields.</jats:p>
収録刊行物
-
- Chemistry – A European Journal
-
Chemistry – A European Journal 11 (3), 849-862, 2005-01-18
Wiley