Convergent synthesis of the pentasaccharide repeating unit of the biofilms produced by Klebsiella pneumoniae

• Arin Gucchait,
• Angana Ghosh and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2019, 15, 431–436, doi:10.3762/bjoc.15.37

• Arin Gucchait Angana Ghosh Anup Kumar Misra Bose Institute, Division of Molecular Medicine, P-1/12, C.I.T. Scheme VII M, Kolkata 700054, India 10.3762/bjoc.15.37 Abstract A pentasaccharide repeating unit containing α-linked D-glucuronic acid, β-linked D-mannose, corresponding to the repeating

• pentasaccharide derivative using phase-transfer reaction conditions furnished the target compound in satisfactory yield. Keywords: beta-D-mannoside; biofilms; D-glucuronic acid; glycosylation; Klebsiella pneumoniae; pentasaccharide; polysaccharide; Introduction Klebsiella pneumoniae (K. pneumoniae) is a Gram

• acid corresponding to the repeating unit of the biofilm producing polysaccharide secreted by K. pneumoniae. The unique feature of this pentasaccharide is that it contains a β-D-mannosidic moiety and a α-D-glucuronic acid moiety, which are known to be challenging from the synthetic point of view. In

Unexpected loss of stereoselectivity in glycosylation reactions during the synthesis of chondroitin sulfate oligosaccharides

• Teresa Mena-Barragán,
• José L. de Paz and
• Pedro M. Nieto

Beilstein J. Org. Chem. 2019, 15, 137–144, doi:10.3762/bjoc.15.14

• and D-glucuronic acid (GlcA) acceptors. These results, together with those obtained from experiments employing model monosaccharide building blocks, highlight the impact of the glycosyl acceptor structure on the stereoselectivity of glycosylation reactions. Our study provides useful data about the

• D-glucuronic acid (GlcA)-β(1→3)-N-acetyl-D-galactosamine (GalNAc)-β(1→4) disaccharides that may contain sulfate groups at different positions. This biopolymer plays a key role in biological events such as brain development and cancer [1]. The preparation of well-defined CS oligosaccharides is

Synthesis of a hexasaccharide partial sequence of hyaluronan for click chemistry and more

• Marina Bantzi,
• Stephan Rigol and
• Athanassios Giannis

Beilstein J. Org. Chem. 2015, 11, 604–607, doi:10.3762/bjoc.11.67

• elucidated in 1954 [6] and since 1986 it is known as “hyaluronan” (HA) [7]. HA is an unbranched polysaccharide, whose disaccharide repeating unit consists of N-acetylglucosamine and D-glucuronic acid conjoined through β-(1→3) and β-(1→4)-glycosidic bonds. Hyaluronan has an average size of 15–20 kDa and does

Triterpenoid saponins from the roots of Acanthophyllum gypsophiloides Regel

• Elena A. Khatuntseva,
• Vladimir M. Men’shov,
• Alexander S. Shashkov,
• Yury E. Tsvetkov,
• Rodion N. Stepanenko,
• Raymonda Ya. Vlasenko,
• Elvira E. Shults,
• Genrikh A. Tolstikov,
• Tatjana G. Tolstikova,
• Dimitri S. Baev,
• Vasiliy A. Kaledin,
• Nelli A. Popova,
• Valeriy P. Nikolin,
• Pavel P. Laktionov,
• Anna V. Cherepanova,
• Tatiana V. Kulakovskaya,
• Ekaterina V. Kulakovskaya and
• Nikolay E. Nifantiev

Beilstein J. Org. Chem. 2012, 8, 763–775, doi:10.3762/bjoc.8.87

• -glucuronic acid (D-GlcA). Similar investigation of compound 2 revealed the same sugar composition as for compound 1. The structures of both compounds 1 and 2 were confirmed on the basis of their 1H NMR, 13C NMR, APT, COSY, TOCSY, ROESY, HSQC, and HMBC spectra. In accordance with the earlier reports [18] on

• , consistent with the molecular formula С75H118O39. GLC analysis of the acetylated (S)-2-octyl glycosides derived after full acid hydrolysis of compound 1 revealed the presence of D-galactose (D-Gal), L-arabinose (L-Ara), 6-deoxy-D-glucose (D-Qui), D-xylose (D-Xyl), L-rhamnose (L-Rha), D-fucose (D-Fuc), and D

Synthesis and antiviral activities of spacer-linked 1-thioglucuronide analogues of glycyrrhizin

• Christian Stanetty,
• Andrea Wolkerstorfer,
• Hassan Amer,
• Andreas Hofinger,
• Ulrich Jordis,
• Dirk Claßen-Houben and
• Paul Kosma

Beilstein J. Org. Chem. 2012, 8, 705–711, doi:10.3762/bjoc.8.79

• -glucuronic acid residues have been prepared in good yields by alkylation of 3-amino and 3-thio derivatives of glycyrrhetinic acid with a 2-iodoethyl 1-thio-β-D-glucopyranosiduronate derivative. The spacer-connected 3-amino derivatives were further transformed into N-acetylated and N-succinylated derivatives

• need for new antiviral compounds. Starting from the natural, antivirally active compound glycyrrhizin, spacer-bridged derivatives were generated with improved antiviral activity against the influenza A virus infection. Simplified analogues of the triterpene saponin glycyrrhizin containing 1-thio-β-D

Convergent synthesis of the tetrasaccharide repeating unit of the O-antigen of Shigella boydii type 9

• Abhishek Santra and
• Anup Kumar Misra

Beilstein J. Org. Chem. 2011, 7, 1182–1188, doi:10.3762/bjoc.7.137

• the presence of acidic constituents (e.g., uronic acid, pseudaminic acid etc. or lactic acid, pyruvic acid etc.) in their structures [6][7]. Recently, L’vov et al. reported the structure of the O-antigen of Shigella boydii type 9, which is a tetrasaccharide repeating unit containing a D-glucuronic

• acid moiety (Figure 1) [8]. Development of effective therapeutics to control the infections of drug-resistant bacterial strains is the thrust area in the medicinal chemistry. Like other bacterial infections, emergence of the drug resistant Shigella infections requires development of the newer