101
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Carvalho I, Scheuerl SL, Ravindranathan Kartha KP, Field RA. Practical synthesis of the 2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-beta-D-glucosides of Fmoc-serine and Fmoc-threonine and their benzyl esters. Carbohydr Res 2003; 338:1039-43. [PMID: 12706969 DOI: 10.1016/s0008-6215(03)00071-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mercuric bromide-promoted glycosylation of Fmoc-Ser-OBn and Fmoc-Thr-OBn with 2-acetamido-2-deoxy-3,4,6-tri-O-acetyl-alpha-D-glucopyranosyl chloride in refluxing 1,2-dichloroethane gave the corresponding beta-glycosides in good yields (64 and 62%, respectively). Direct coupling of the commercially available Fmoc-Ser-OH and Fmoc-Thr-OH carboxylic acids under similar conditions gave the corresponding beta-glycosides, possessing free carboxyl groups, in moderate yields (50 and 40%, respectively).
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Affiliation(s)
- Ivone Carvalho
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Brazil
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102
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Messner P, Schäffer C. Prokaryotic glycoproteins. FORTSCHRITTE DER CHEMIE ORGANISCHER NATURSTOFFE = PROGRESS IN THE CHEMISTRY OF ORGANIC NATURAL PRODUCTS. PROGRES DANS LA CHIMIE DES SUBSTANCES ORGANIQUES NATURELLES 2003; 85:51-124. [PMID: 12602037 DOI: 10.1007/978-3-7091-6051-0_2] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- P Messner
- Zentrum für Ultrastrukturforschung, Ludwig-Boltzmann-Institut für Molekulare Nanotechnologie, Universität für Bodenkultur Wien, Austria
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103
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Tetrahedron reports on organic chemistry. Tetrahedron 2003. [DOI: 10.1016/s0040-4020(03)00323-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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104
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Abstract
The synthesis of several new sugar amino acid derivatives of 2-acetamido-2-deoxy-D-glucose, bearing a C-glycosyl functionality as building blocks for the design and synthesis of natural glycoconjugates mimetics, is described. These compounds were prepared from the readily accessible per-benzylated amino C-allyl glucopyranosyl compounds, with TMSOTf/Ac(2)O-mediated selective acetolysis of the 6-O-benzyl group as the key step.
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Affiliation(s)
- Juan Xie
- Laboratoire de Chimie des Glucides, CNRS UMR 7613, Université Pierre et Marie Curie, 4 Place Jussieu, F-75005, Paris, France.
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105
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Posner G, Motherwell W. Tetrahedron reports on organic chemistry. Tetrahedron 2002. [DOI: 10.1016/s0040-4020(02)01503-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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106
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107
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108
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Pachamuthu K, Gupta A, Das J, Schmidt R, Vankar Y. An Easy Route to 2-Amino-β-C-Glycosides by Conjugate Addition to 2-Nitroglycals. European J Org Chem 2002. [DOI: 10.1002/1099-0690(200205)2002:9<1479::aid-ejoc1479>3.0.co;2-p] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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109
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Paterson D, Griffin F, Alcaraz ML, Taylor R. A Ramberg−Bäcklund Approach to the Synthesis ofC-Glycosides,C-Linked Disaccharides, andC-Glycosyl Amino Acids. European J Org Chem 2002. [DOI: 10.1002/1099-0690(200204)2002:7<1323::aid-ejoc1323>3.0.co;2-8] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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110
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Risley JM, Huang DH, Kaylor JJ, Malik JJ, Xia YQ. Glycosylasparaginase inhibition studies: competitive inhibitors, transition state mimics, noncompetitive inhibitors. JOURNAL OF ENZYME INHIBITION 2002; 16:269-74. [PMID: 11697047 DOI: 10.1080/14756360109162375] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Glycosylasparaginase catalyzes the hydrolysis of the N-glycosylic bond between asparagine and N-acetylglucosamine in the catabolism of N-linked glycoproteins. Previously only three competitive inhibitors, one noncompetitive inhibitor, and one irreversible inhibitor of glycosylasparaginase activity had been reported. Using human glycosylasparaginase from human amniotic fluid, L-aspartic acid and four of its analogues, where the alpha-amino group was substituted with a chloro, bromo, methyl or hydrogen, were competitive inhibitors having Ki values between 0.6-7.7 mM. These results provide supporting evidence for a proposed intramolecular autoproteolytic activation reaction. A proposed phosphono transition state mimic and a sulfo transition state mimic were competitive inhibitors with Ki values 0.9 mM and 1.4 mM, respectively. These results support a mechanism for the enzyme-catalyzed reaction involving formation of a tetrahedral high-energy intermediate. Three analogues of the natural substrate were noncompetitive inhibitors with Ki values between 0.56-0.75 mM, indicating the presence of a second binding site that may recognize (substituted)acetamido groups.
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Affiliation(s)
- J M Risley
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC 28223, USA.
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111
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Affiliation(s)
- Benjamin G Davis
- Dyson Perrins Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QY, UK.
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112
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Gruner SAW, Locardi E, Lohof E, Kessler H. Carbohydrate-based mimetics in drug design: sugar amino acids and carbohydrate scaffolds. Chem Rev 2002; 102:491-514. [PMID: 11841252 DOI: 10.1021/cr0004409] [Citation(s) in RCA: 328] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sibylle A W Gruner
- Institut für Organische Chemie und Biochemie, Technische Universität München, Lichtenbergstrasse 4, D-85747 Garching, Germany
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113
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Expedient synthesis of aminooxylated-carbohydrates for chemoselective access of glycoconjugates. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(01)01614-8] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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114
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Xie J, Thellend A, Becker H, Vidal-Cros A. Synthesis and evaluation of a C-glycosyl nucleoside as an inhibitor of chitin synthase. Carbohydr Res 2001; 334:177-82. [PMID: 11513824 DOI: 10.1016/s0008-6215(01)00191-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
As part of our ongoing program devoted to inhibit chitin synthases, we have prepared a novel C-glycosyl nucleoside as metabolically stable substrate analog of UDP-GlcNAc. The synthetic strategy relies on the consecutive coupling of nucleoside and amino C-glycosyl moieties with L-tartaric acid. However, this compound inhibited only weakly chitin synthase I, with an IC(50) value of 20 mM.
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Affiliation(s)
- J Xie
- Laboratoire de Chimie des Glucides, Université Pierre et Marie Curie, CNRS UMR 7613, 4 Place Jussieu, F-75005 Paris, France.
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115
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Synthesis of new α- and β-gem-difluoromethylene C-glycosides in the galactose and glucose series. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(01)01144-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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116
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Risley JM, Huang DH, Kaylor JJ, Malik JJ, Xia YQ, York WM. Glycosylasparaginase activity requires the alpha-carboxyl group, but not the alpha-amino group, on N(4)-(2-Acetamido-2-deoxy-beta-D-glucopyranosyl)-L-asparagine. Arch Biochem Biophys 2001; 391:165-70. [PMID: 11437347 DOI: 10.1006/abbi.2001.2416] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Glycosylasparaginase catalyzes the hydrolysis of the N-glycosylic bond in N(4)-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-L-asparagine in the catabolism of N-linked oligosaccharides. A deficiency, or absence, of enzyme activity gives rise to aspartylglycosaminuria, the most common disorder of glycoprotein metabolism. The enzyme catalyzes the hydrolysis of a variety of asparagine and aspartyl compounds containing a free alpha-carboxyl group and a free alpha-amino group; computational studies suggest that the alpha-amino group actively participates in the catalytic mechanism. In order to study the importance of the alpha-carboxyl group and the alpha-amino group on the natural substrate to the reaction catalyzed by the enzyme, 14 analogues of the natural substrate were studied where the structure of the aspartyl group of the substrate was changed. The incremental binding energy (DeltaDeltaGb) for those analogues that were substrates was calculated. The results show that the alpha-amino group may be substituted with a group of comparable size, for the alpha-amino group contributes little, if any, to the transition state binding energy of the natural substrate. The alpha-amino group position acts as an "anchor" in the binding site for the substrate. On the other hand, the alpha-carboxyl group is necessary for enzyme activity; removal of the alpha-carboxyl group or changing it to an alpha-carboxamide group results in no hydrolysis reaction. Also, N-acetyl-D-glucosamine is not sufficient for binding to the active site for efficient hydrolysis by the enzyme. These results provide supporting evidence for a proposed intramolecular autoproteolytic activation reaction for the enzyme. However, the results raise a question as to an important role for the alpha-amino group in the catalytic mechanism as indicated in computational studies.
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Affiliation(s)
- J M Risley
- Department of Chemistry, The University of North Carolina at Charlotte, Charlotte, North Carolina 28223, USA.
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117
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Lenz DH, Norris GE, Taylor CM, Slim GC. One-pot transformation of glycopyranosylcyanides to N-(t-butoxycarbonyl)methylamines. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(01)00804-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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118
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An easy access to anomeric glycosyl amides and imines(Schiff bases) via transformation of glycopyranosyl trimethylphosphinimides. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00380-5] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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119
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Seitz O, Heinemann I, Mattes A, Waldmann H. Synthetic peptide conjugates—tailor-made probes for the biology of protein modification and protein processing. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(00)01115-7] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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120
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Xia YQ, Risley JM. SYNTHESIS OFN4-(2-ACETAMIDO-2-DEOXY-β-D-GLUCOPYRANOSYL)-L-ASPARAGINE ANALOGUES.L-2-CHLORO-,L-2-BROMO-, ANDD,L-2-METHYLSUCCINAMIC ACID ANALOGUES. J Carbohydr Chem 2001. [DOI: 10.1081/car-100102542] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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121
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Fahmi NE, Golovine S, Wang B, Hecht SM. Studies toward the site specific incorporation of sugars into proteins: synthesis of glycosylated aminoacyl-tRNAs. Carbohydr Res 2001; 330:149-64. [PMID: 11217968 DOI: 10.1016/s0008-6215(00)00289-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
A series of glycosylated serine derivatives was synthesized from peracetylated sugars and Fmoc-protected serine; these were chemically esterified with the tris-(tetrabutylammonium) salt of pdCpA. The fully protected and deprotected glycosylated aminoacyl pdCpAs were ligated enzymatically to an abbreviated tRNA (tRNA-C(OH)) to provide the title compounds that are key intermediates in the elaboration of glycoproteins using readthrough of a nonsense codon.
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Affiliation(s)
- N E Fahmi
- Department of Chemistry, University of Virginia, Charlottesville 22901, USA
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122
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Tarantini L, Monti D, Panza L, Prosperi D, Riva S. Enzymatic galactosylation of C-glycosides analogues en route to C-glycopeptides. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s1381-1177(00)00020-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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123
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Dondoni A, Marra A. Methods for anomeric carbon-linked and fused sugar amino Acid synthesis: the gateway to artificial glycopeptides. Chem Rev 2000; 100:4395-422. [PMID: 11749352 DOI: 10.1021/cr9903003] [Citation(s) in RCA: 227] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A Dondoni
- Dipartimento di Chimica, Laboratorio di Chimica Organica, Università di Ferrara, Via L. Borsari 46, 44100 Ferrara, Italy
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124
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Hanessian S, Lou B. Stereocontrolled glycosyl transfer reactions with unprotected glycosyl donors. Chem Rev 2000; 100:4443-64. [PMID: 11749354 DOI: 10.1021/cr9903454] [Citation(s) in RCA: 135] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S Hanessian
- Advanced SynTech, 9800 Bluegrass Parkway, Louisville, Kentucky 40299
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125
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De Huang H, Risley JM. Synthesis of N4-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-L-asparagine analogues: succinamide, L-2-hydroxysuccinamide, and L-2-hydroxysuccinamic acid hydrazide analogues. Carbohydr Res 2000; 329:487-93. [PMID: 11128578 DOI: 10.1016/s0008-6215(00)00224-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The syntheses of three analogues of N4-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-L-asparagine are described. N-(2-Acetamido-2-deoxy-beta-D-glucopyranosyl)succinamide was synthesized by the reaction of pentafluorophenyl succinamate with 2-acetamido-2-deoxy-beta-D-glucopyranosylamine. 2-Acetamido-3,4,6-tri-O-acetyl-2-deoxy-beta-D-glucopyranosylamine was synthesized, and the complete assignment of the 1H NMR spectrum is given. Reaction of the protected beta-D-glycosylamine with L-malic acid chloralid in the presence of a coupling agent (EEDQ) gave N4-(2-acetamido-3,4,6-tri-O-acetyl-2-deoxy-beta-D-glucopyranosyl)-L-malamic acid chloralid that was deprotected two ways: (1) using ammonia, which gave N4-(2-acetamido-2-deoxy-beta-D-glucopyranosyl)-L-2-hydroxysuccinamide, and (2) using hydrazine, which gave N4-(2-acetamido-2-deoxy-1-D-glucopyranosyl)-L-2-hydroxysuccinamic acid hydrazide.
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Affiliation(s)
- H De Huang
- Department of Chemistry, University of North Carolina at Charlotte, 28223, USA
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126
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Abstract
Despite the omnipresence of protein glycosylation in nature, little is known about how the attachment of carbohydrates affects peptide and protein activity. One reason is the lack of a straightforward method to access biologically relevant glycopeptides and glycoproteins. The isolation of homogeneous glycopeptides from natural sources is complicated by the heterogeneity of naturally occuring glycoproteins. It is chemical and chemoenzymatic synthesis that is meeting the challenge to solve this availability problem, thus playing a key role for the advancement of glycobiology. The current art of glycopeptide synthesis, albeit far from being routine, has reached a level of maturity that allows for the access to homogeneous and pure material for biological and medicinal research. Even the ambitious goal of the total synthesis of an entire glycoprotein is within reach. It is demonstrated that with the help of synthetic glycopeptides the effects of glycosylation on protein structure and function can be studied in molecular detail. For example, in immunology, synthetic (tumour-specific) glycopeptides can be used as immunogens to elicit a tumour-cell-specific immune response. Again, synthetic glycopeptides are an invaluable tool to determine the fine specificity of the immune response that can be mediated by both carbohydrate-specific B and T cells. Furthermore, selected examples for the use of synthetic glycopeptides as ligands of carbohydrate-binding proteins and as enzyme substrates or inhibitors are presented.
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Affiliation(s)
- O Seitz
- Department of Chemical Biology Max-Planck-Institut für molekulare Physiologie Otto-Hahn-Strasse 11, 44227 Dortmund, Germany.
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127
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128
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Abstract
Efficient synthesis of unprotected S-glycoamino acid building blocks in the solid phase by coupling a sugar 1-thiolate with iodine activated fluoren-9-ylmethoxycarbonyl (Fmoc) protected amino acids.
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Affiliation(s)
- L Jobron
- Jerini Bio Tools GmbH, Rudower Chaussee 29, 12489 Berlin, Germany
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129
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Ohnishi Y, Ichikawa M, Ichikawa Y. Facile synthesis of N-Fmoc-serine-S-GlcNAc: a potential molecular probe for the functional study of O-GlcNAc. Bioorg Med Chem Lett 2000; 10:1289-91. [PMID: 10866402 DOI: 10.1016/s0960-894x(00)00223-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
A metabolically stable beta-N-acetylglucosaminyl-1-thio-N-Fmoc-serine (S-GlcNAc-Ser) derivative was synthesized in two procedures: one involving a coupling of a readily obtainable 1-pseudo-thiourea of GlcNAc (S-GlcNAc) and iodo-N-Boc-L-alanine benzyl ester, and the other utilizing a modified Mitsunobu reaction of GlcNAc-SH and a serine derivative.
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Affiliation(s)
- Y Ohnishi
- Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
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130
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Shin Y, Winans KA, Backes BJ, Kent SBH, Ellman JA, Bertozzi CR. Fmoc-Based Synthesis of Peptide-αThioesters: Application to the Total Chemical Synthesis of a Glycoprotein by Native Chemical Ligation. J Am Chem Soc 1999. [DOI: 10.1021/ja992881j] [Citation(s) in RCA: 307] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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131
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Westermann B, Walter A, Diedrichs N. Diastereoselektive Synthese von C-glycosylierten Aminosäuren mit Lactamen als Peptidbausteinen. Angew Chem Int Ed Engl 1999. [DOI: 10.1002/(sici)1521-3757(19991115)111:22<3554::aid-ange3554>3.0.co;2-u] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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132
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Hoffmann R, Craik DJ, Bokonyi K, Varga I, Otvos L. High level of aspartic acid-bond isomerization during the synthesis of an N-linked tau glycopeptide. J Pept Sci 1999; 5:442-56. [PMID: 10580643 DOI: 10.1002/(sici)1099-1387(199910)5:10<442::aid-psc214>3.0.co;2-q] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
An increased degree of utilization of the potential N-glycosylation site in the fourth repeat unit of the human tau protein may be involved in the inability of tau to bind to the corresponding tubulin sequence(s) and in the subsequent development of the paired helical filaments of Alzheimer's disease. To model these processes, we synthesized the octadecapeptide spanning this region without sugar, and with the addition of an N-acetyl-glucosamine moiety. The carbohydrate-protected, glycosylated asparagine was incorporated as a building block during conventional Fmoc-solid phase peptide synthesis. While the crude non-glycosylated analog was obtained as a single peptide, two peptides with the identical, expected masses, in approximately equal amounts, were detected after the cleavage of the peracetylated glycopeptide. Surprisingly, the two glycopeptides switched positions on the reversed-phase high performance liquid chromatogram after removal of the sugar-protecting acetyl groups. Nuclear magnetic resonance spectroscopy and peptide sequencing identified the more hydrophobic deprotected peak as the target peptide, and the more hydrophilic deprotected peak as a peptide analog in which the aspartic acid-bond just preceding the glycosylated asparagine residue was isomerized resulting in the formation of a beta-peptide. The anomalous chromatographic behavior of the acetylated beta-isomer could be explained on the basis of the generation of an extended hydrophobic surface which is not present in any of the other three glycopeptide variants. Repetition of the syntheses, with altered conditions and reagents, revealed reproducibly high levels of aspartic acid-bond isomerization of the glycopeptide as well as lack of isomerization for the non-glycosylated parent analog. If similar increased aspartic acid-bond isomerization occurs in vivo, a protein modification well known to take place for both the amyloid deposits and the neurofibrillary tangles in Alzheimer's disease, this process may explain the aggregation of glycosylated tau into the paired helical filaments in the affected brains.
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Affiliation(s)
- R Hoffmann
- The Wistar Institute, Philadelphia, PA 19104, USA
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133
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Knapp S, Malolanarasimhan K. Oligomeric Thioglycosides with α-d-manno-(1‘→2) Linkages from a Glycal-1,2-episulfide. Org Lett 1999. [DOI: 10.1021/ol990702x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Spencer Knapp
- Department of Chemistry, Rutgers−The State University of New Jersey, New Brunswick, New Jersey 08854-8087
| | - Krishnan Malolanarasimhan
- Department of Chemistry, Rutgers−The State University of New Jersey, New Brunswick, New Jersey 08854-8087
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134
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Affiliation(s)
- Klaus Burger
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie der Universität, Talstraße 35, D‐04103 Leipzig, Fax: (+ 49) 341‐9736529
| | - Michael Kluge
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie der Universität, Talstraße 35, D‐04103 Leipzig, Fax: (+ 49) 341‐9736529
| | - Susanna Fehn
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie der Universität, Talstraße 35, D‐04103 Leipzig, Fax: (+ 49) 341‐9736529
| | - Beate Koksch
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie der Universität, Talstraße 35, D‐04103 Leipzig, Fax: (+ 49) 341‐9736529
| | - Lothar Hennig
- Institut für Organische Chemie, Fakultät für Chemie und Mineralogie der Universität, Talstraße 35, D‐04103 Leipzig, Fax: (+ 49) 341‐9736529
| | - Gerhard Müller
- Bayer AG, Zentrale Forschung, ZF‐WFM, Gebäude Q 18, D‐51368 Leverkusen
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135
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Gyóllai V, Somsák L, Szilágyi L. N-(1-cyano-d-glycosyl)amides — Novel anomeric α-amino-acid derivatives. Tetrahedron Lett 1999. [DOI: 10.1016/s0040-4039(99)00623-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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