作者:Hernán A. Orgueira、Alessandra Bartolozzi、Peter Schell、Remy E. J. N. Litjens、Emma R. Palmacci、Peter H. Seeberger
DOI:10.1002/chem.200390009
日期:2003.1.3
uronic acid glycosyl acceptors thereby establishing a new concept for stereochemicalcontrol. Combination of disaccharide modules to form trans-uronic acid linkages was completely selective by virtue of C2 participating groups. Coupling reactions between disaccharide modules exhibited sequence dependence. While the union of many glucosamine uronic acid disaccharide modules did not meet any problems, certain
RNA monomers containing O-acetal levulinyl ester groups and their use in RNA microarrays
申请人:Damha Masad
公开号:US09249175B2
公开(公告)日:2016-02-02
The present invention is directed to RNA monomers comprising O-acetal levulinyl protecting groups at the 2′ and/or the 5′-hydroxy functionalities of the ribose moiety. Said monomers may be incorporated into oligoribonucleotides or RNA polynucleotides. Furthermore, the invention is directed to methods for the synthesis of said RNA monomers, oligoribonucleotides and RNA polynucleotides, as well as methods for their deprotection and methods for the use of said compounds and compositions comprising said compounds. In particular, such compounds and compositions comprising them are used in methods for light-directed synthesis of RNA microarrays.
A bio‐inspired approach for efficient conversion of cellulose to formicacid (FA) was developed in an aqueous alkaline medium. Metalloporphyrins mimicking cytochrome P450 exhibit efficiently and selectively catalytic performance in catalytic conversion of cellulose. High yield of FA about 63.7% was obtained by using sulfonated iron(III) porphyrin as the catalyst and O2 as the oxidant. Iron(III)‐peroxo
在碱性水溶液中开发了一种由生物启发的方法,可将纤维素有效地转化为甲酸(FA)。模仿细胞色素P450的金属卟啉在纤维素的催化转化中表现出有效和选择性的催化性能。用磺化的卟啉铁(III)作催化剂,用O 2作氧化剂,可得到约63.7%的高FA 。铁(III)μ-过氧物种,TSPPFe III OO - ,参与切割葡糖酸到FA的C-C键在该催化体系。该方法使用相对较高浓度的纤维素和ppm浓度的催化剂。这项工作可能提供了一种由生物启发的途径,可以有效地将纤维素转化为FA。
Toward the assembly of heparin and heparan sulfate oligosaccharide libraries: efficient synthesis of uronic acid and disaccharide building blocks
作者:Akihiro Saito、Masahiro Wakao、Hiroshi Deguchi、Aya Mawatari、Michael Sobel、Yasuo Suda
DOI:10.1016/j.tet.2010.03.077
日期:2010.5
The monosaccharide moieties found in heparin (HP) and heparan sulfate (HS), glucosamine and two kinds of uronic acids, glucuronic and iduronic acids, were efficiently synthesized by use of glucosamine hydrochloride and glucurono-6,3-lactone as starting compounds. In the synthesis of the disaccharide building block, the key issues of preparation of uronic acids (glucuronic acid and iduronic acid moieties)
Enantioselective syntheses of α-substituted glutamic acids and α,γ-disubstituted glutamic acids by an asymmetric Strecker reaction
作者:Dawei Ma、Guozhi Tang、Hongqi Tian、Guixiang Zou
DOI:10.1016/s0040-4039(99)01121-1
日期:1999.7
The Strecker reaction of the product from the treatment of the sodium salt of γ-keto acids with (S)-phenylglycinol followed by heating the products to 200 °C gives the bicyclic lactones 9 and 10. Alkylation of 9 provides 11 and 12. Both 9b and 11a are converted into the corresponding substituted glutamicacids via reductive cleavage and hydrolysis.