ChemInform Abstract: CARBON‐13 NUCLEAR MAGNETIC RESONA

Vuilhorgne, Marc; Ennifar, Sofiane; Das, Bhupesh C.; Paschal, Jonathan W.; Ramakrishnan, Nagarajan; Hagaman, Edward W.; Wenkert, Ernest

doi:10.1002/chin.197803379

Cited by 5 publications

(11 citation statements)

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“…The reaction between the dialdose derivative (3) and (methoxycarbonylmethy1ene)triphenylphosphorane in methanol at ca. 4°C furnished the (a-olefin (8), which then gave (2)-6,7-dideoxy-1,2 : 3,4-di-O-isopropylidene-a-~-galacrooct-6-enopyranose (9) on reduction with lithium aluminium hydride. ' H N.m.r.…”

Section: Resultsmentioning

confidence: 99%

“…In most instances, the stereochemical outcome of the osmylation reactions can be predicted by Kishi's empircal rule," the osmylation of the conjugate ester (8) providing a notable exception. The following paper describes further two-carbon extension of the chain of such octose sugars as (18) and (33) (2)-6,7-Dideoxy-1,2 : 3,4-di-0-isopropylidene-a-~-galacto-oct -6-enopyranose (9).-Lithium aluminium hydride (0.362 g, ca. 9.5 mmol) was added gradually to a cooled (0 "C) and stirred solution of the conjugate ester (8) …”

Section: Resultsmentioning

confidence: 99%

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Higher-carbon sugars. Part 1. The synthesis of some octose sugars via the osmylation of unsaturated precursors

Brimacombe¹,

HANNA²,

Kabir³

et al. 1986

J. Chem. Soc., Perkin Trans. 1

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The stereochemical outcome of the osmium tetraoxide oxidation of a number of unsaturated carbohydrate derivatives, including (€) -and (Z) -6,7-dideoxy-l,2 : 3,4-di-~-isopropylidene-a-o-ga/acto-oct-6-enopyranose (6) and (9), methyl (Z) -6,7 -dideoxy-1,2 : 3,4-di -0-isopropylidene-a-D-galacto-oct -6-enopyranuronate ( 8 ) , and 7,8-dideoxy-1,2 : 3,4-di-0-isopropylidene-a-D-glycero-~-ga/acto-oct-7 -enopyranose (1 0), has been examined. Such oxidations resulted in the preparation of the synthetically usef u I octose derivatives 1,2 : 3,4-d i -0 -isopropy l idene-x -D -erythro -D -ga/acto -octopyranose (1 8) and 1,2: 3,4: 6,7-tr~-~-~sopropyl~dene-~-~-erythro-~-ga/acto-octopyranose (31 ), as well as syntheses of Lthreo-D -ga/acto-octitol (1 4), D-erythro -D-ga/acto-octitol (21 ), L-erythro-o-galacto-octitoi (29), and D -threo -D-ga/aCtO-OCtitOI (35).The synthesis of sugars with carbon chains composed of more than six carbon atoms, the so-called higher-carbon sugars,' poses an interesting challenge.'-4 Such syntheses require the formation of carbon-carbon bonds and control of the stereochemistry at each newly created stereocentre. The concept of asymmetric synthesis was first realised with the Kiliani-Fischer cyanohydrin reaction, which was used to extend the aldose chain by one carbon atom from the reducing end.2*3 This procedure has been applied to most h e x o s e~,~.~ but, because of the asymmetric nature of the cyanohydrin synthesis, only a limited number of heptoses are available as substrates. In certain cases, syntheses were extended to give octose, nonose, and decose sugars, but the structures of many of these highercarbon sugars remain unproved.' In recent times, the cyanohydrin procedure has been augmented by other methods; ' theseO+ permit extension of the sugar chain by two or more carbon atoms in a single step, but seldom in a wholly predictable way, so that in spite of the long standing interest in higher-carbon sugars, only a handful of them containing eight or more carbon atoms are known.2 A resurgence of interest in the synthesis of higher-carbon sugars has followed the discovery of important antibiotics containing such higher-carbon sugars as the amino-octodioses (1) (from apramycin and oxyapramycin ') and the undecose hikosamine 8*9 (2) (from hikizimycin 9). Our interest in the synthesis of these and other higher-carbon sugars of biological interest prompted an examination of the oxidation of various unsaturated sugar derivatives with osmium tetraoxide. In choosing this approach we were influenced by the knowledge that the osmylation of allylic alcohols and ethers proceeds with moderate to marked stereoselectivity, which can be predicted on an empirical basis. l o Initially our efforts were directed towards the synthesis of octose sugars by extending the chain of the hexodialdose" (3) by two carbon atoms, as outlined in the Scheme. Unlike traditional methods, the carbon chain of the original hexose, in this instance D-galactose, is undergoing extension from the non-reducing end. This particular system...

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Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Higher-carbon sugars. Part 1. The synthesis of some octose sugars via the osmylation of unsaturated precursors

Brimacombe¹,

HANNA²,

Kabir³

et al. 1986

J. Chem. Soc., Perkin Trans. 1

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“…longissimus and Str. Hikiziensis [39]. Analysis of the degradation products revealed that anthelmycin contains cytosine, 3-amino-3-deoxy-D-glucopyranose (canosamine) and 4-aminoundecose (hikosamine).…”

Section: Natural Disaccharide Nucleosidesmentioning

confidence: 98%

“…Analysis of the degradation products revealed that anthelmycin contains cytosine, 3-amino-3-deoxy-D-glucopyranose (canosamine) and 4-aminoundecose (hikosamine). The -configurations of O-and N-glycosidic bonds of both amino sugars were established by NMR spectroscopy [39]. The antibiotic manifests antiparasitic and fungicidal properties and inhibits prokaryotic and eukaryotic peptidyl transferase [40].…”

Section: Natural Disaccharide Nucleosidesmentioning

confidence: 99%

Disaccharide Nucleosides and their Incorporation into Oligonucleotides

Efimtseva¹,

Kulikova²,

Mikhailov³

2007

COC

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The review summarizes structural features, biological activity and synthetic methods of disaccharide nucleosides. In the first part the structures of natural disaccharide nucleosides are presented. The consequent part deals with general methods of synthesis of these compounds -formation of new N-and O-glycosidic bonds. Recent achievements in the preparation of disaccharide nucleosides from natural nucleosides are discussed. The last part is devoted to the synthesis and properties of oligonucleotides containing disaccharide nucleosides.Disaccharide nucleosides belong to an important group of natural compounds forming poly(ADP-ribose) and found in tRNA, antibiotics, and other physiologically active compounds. To date about a hundred disaccharide nucleoside and related derivatives have been isolated from various natural sources. These compounds contain an extra carbohydrate residue linked to one of the nucleoside hydroxyl groups via an O-glycosidic bond. The presence of a disaccharide residue and a heterocyclic base makes their properties similar to those of carbohydrates and nucleosides. These compounds manifest a broad spectrum of biological (including antibacterial, fungicidal, herbicidal, antitumour and antiviral) activities. The review by Lerner [1] published in 1991 provides a detailed description of the structures of disaccharide nucleoside antibiotics and the approaches to their synthesis. Some of the published data on the synthesis of complex nucleoside antibiotics were summarized by Knapp [2]. Since that time, many new publications devoted to this problem have appeared in the current literature. In our recent publiccations physicochemical properties [3], structure and general synthetic approaches to the synthesis [4] of disaccharide nucleosides were reviewed. Here we describe structural peculiarities of disaccharide nucleosides and summarize our recent data on their synthesis and incorporation into oligonucleotides (ONs). NATURAL DISACCHARIDE NUCLEOSIDESThe structures of disaccharide nucleosides are extremely diverse [5,6] and their elucidation is a rather complicated task. In addition to a heterocyclic base and two mono-saccharide residues, these compounds contain various functional substituents, such as acyl and alkyl groups as well as phosphate and sulfate residues, fatty acids, amino acids, peptides and additional sugars. Their degradation by acid and alkaline hydrolysis or methanolysis, periodate oxidation and subsequent reduction yields fragments the structures of which can be established by physicochemical methods. At present, the structures of many complex antibiotics are determined mainly by NMR spectroscopy and mass spectrometry.According to their structure natural disaccharide nucleosides may be divided into three main groups. Disaccharide nucleosides belonging to the first two groups contain natural purine nucleoside. In the first group additional ribofuranosyl residue is attached via O-glycosidic bond to the adenosine or guanosine. Most of these derivatives were found in biopolymers. 2 (3 )-O-...

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“…hikiziensis. 28,29 Analysis of the degradation products of compound 22 revealed that the latter contains cytosine, 3-amino-3-deoxy-D-glucopyranose (canosamine) and 4-aminoundecose (hikosamine). 29,30 The b-configurations of Oand N-glycosidic bonds of both amino sugars were established by NMR spectroscopy.…”

Section: Structures and Properties Of Natural Disaccharide Nucleoside...mentioning

confidence: 99%

Disaccharide nucleosides

Efimtseva¹,

Mikhailov²

2004

Russ. Chem. Rev.

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Structural features and biological properties of naturalStructural features and biological properties of natural disaccharide nucleosides and related compounds are considered. disaccharide nucleosides and related compounds are considered. The main methods for the synthesis of these compounds are The main methods for the synthesis of these compounds are described and their advantages and disadvantages are discussed. described and their advantages and disadvantages are discussed. These methods include condensations of a protected disaccharide These methods include condensations of a protected disaccharide with a heterocyclic base or of a protected nucleoside with an with a heterocyclic base or of a protected nucleoside with an activated monosaccharide. The bibliography includes 172 refer-activated monosaccharide. The bibliography includes 172 references ences. .

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ChemInform Abstract: CARBON‐13 NUCLEAR MAGNETIC RESONA

Abstract: Für das antibiotische Anthelmycin 148 wird die Struktur (I) bestätigt.

Cited by 5 publications

References 1 publication

Higher-carbon sugars. Part 1. The synthesis of some octose sugars via the osmylation of unsaturated precursors

Higher-carbon sugars. Part 1. The synthesis of some octose sugars via the osmylation of unsaturated precursors

Disaccharide Nucleosides and their Incorporation into Oligonucleotides

Disaccharide nucleosides

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