Synthesis of clustered D-GalNAc (Tn) and D-Galβ(1→3)GalNAc (T) antigenic motifs using a pentaerythritol scaffold

1996 ◽  
Vol 74 (9) ◽  
pp. 1738-1747 ◽  
Author(s):  
Stephen Hanessian ◽  
Dongxu Qiu ◽  
Hubli Prabhanjan ◽  
Gurijala V. Reddy ◽  
Boliang Lou
Keyword(s):  
Key Words ◽  
Carbohydrate Antigens ◽  
Glycoside Synthesis ◽  
Derivatives Of ◽  
Glycosyl Donors

The tris(aminoethyl) and triamino derivatives of pentaerythritol have been used as scaffolds or templates for the attachment of immunologically relevant carbohydrates such as D-Galβ(1→3)GalNAc (T) and GalNAc (Tn), through amide linkages with the respective α-glycolyl and α-N-acetyl-L-serinyl glycosides. These clustered glycosidic motifs are intended as haptens for use in the preparation of tumor specific carbohydrate antigens and vaccines. Key words: glycoside synthesis, 2-thiopyridyl carbonate, glycosyl donors and glycopeptide motifs

Acyl cyanides as carbonyl heterodienophiles: application to the synthesis of naphthols, isoquinolones, and isocoumarins

1996 ◽  
Vol 74 (2) ◽  
pp. 221-226 ◽  
Author(s):  
Richard Connors ◽  
Elisabeth Tran ◽  
Tony Durst
Keyword(s):  
Key Words ◽  
Diels Alder ◽  
Acetonitrile Solution ◽  
Carbon And Nitrogen ◽  
Nitrogen Nucleophiles ◽  
Derivatives Of

Irradiation of 2-methylbenzoyl cyanide (3a) in acetonitrile solution results in the formation of its dimer, which upon loss of HCN gives rise to the cycloadduct 7a. The dimerization also proceeds efficiently with derivatives of 3a giving adducts 7b and 7c. When 2-methylaroyl cyanides are photolyzed in the presence of a more reactive acyl cyanide the mixed adducts 8a–e are obtained in excellent yields. The cycloadducts 7a–c and 8a–e react with carbon and nitrogen nucleophiles by a tandem addition–cyclization sequence furnishing substituted naphthols (10a and 10b) and isoquinolones (11a–d), respectively. Isocoumarins 12a and 12b were prepared from the adducts 8a and 8e by treatment with potassium tert-butoxide in THF. Key words: naphthols, isoquinolones, isocoumarins, synthesis of; acyl cyanides; hetero Diels–Alder.

Cycloaddition d'ylures d'azométhine dérivés de la 3,4-dihydro-6,7-diméthoxy-3-méthoxycarbonyl-isoquinoléine

1991 ◽  
Vol 69 (7) ◽  
pp. 1156-1160 ◽  
Author(s):  
Tahar Lakhlifi ◽  
Ahmed Sedqui ◽  
Bernard Laude ◽  
Nguyen Dinh An ◽  
Joël Vebrel
Keyword(s):  
Magnetic Resonance ◽  
Key Words ◽  
Proton Magnetic Resonance ◽  
Azomethine Ylide ◽  
Magnetic Resonance Data ◽  
Resonance Data ◽  
Azabicyclic Compounds ◽  
Derivatives Of ◽  
Proton Magnetic Resonance Data

Three azomethine ylide precursors including the methyl 3,4-dihydro-6,7-dimethoxyisoquinoline-3carboxylate moiety were synthesized. The 1,3-dipolar species formed from these products react with activated dipolarophilic olefines leading diastereospecifically to derivatives of 4′,5′-dimethoxy-1,2-benzo-4,7-imino-4-methoxycarbonyl-1-cycloheptene. Proton magnetic resonance data allowed the determination of the stereochemistry of the cycloadducts. Key words: cyclic azomethine ylide, azabicyclic compounds, stereochemistry.

N-Thiodiglycoloyl derivatives of glucosamine as glycosyl donors

2000 ◽  
Vol 41 (5) ◽  
pp. 629-632 ◽  
Author(s):  
Julio C Castro-Palomino ◽  
Richard R Schmidt
Keyword(s):  
Derivatives Of ◽  
Glycosyl Donors

ChemInform Abstract: Nucleophilic C-Glycosyl Donors for C-Glycoside Synthesis

ChemInform ◽  
2010 ◽  
Vol 28 (34) ◽  
pp. no-no ◽  
Author(s):  
J.-M. BEAU ◽  
T. GALLAGHER
Keyword(s):  
Glycoside Synthesis ◽  
Glycosyl Donors

SEMI-SYNTHESIS AND EVALUATION OF HESPERETIN DERIVATIVES AS ACETYLCHOLINESTERASE INHIBITORS7

2018 ◽  
Vol 8 (4) ◽  
pp. 7-12
Author(s):  
Huan Tran The ◽  
Dao Tran Thanh
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Key Words ◽  
Inhibitory Activity ◽  
Acetylcholinesterase Inhibitory Activity ◽  
Ic50 Value ◽  
Ellman’S Method ◽  
Further Development ◽  
Derivatives Of

Background: Inhibition of acetylcholinesterase are regarded as one of promising approach to treat Alzheimer’s disease. Hesperetin is a potential flavonoid for further development in this direction. Objectives: Semi-synthesized and assayed for hesperetin derivatives’s acetylcholinesterase inhibitory activity in vitro. Materials and methods: Ester and ether derivatives of hesperetin were semi-synthesized. The semi-synthesis compounds were tested for acetylcholinesterase inhibitory activity in vitro according to the Ellman’s method. Results: Hesperetin is obtained by hydrolysing hesperidin. Then, two ester and two ether derivatives were semi-synthesized from hesperetin. The results showed that some of the semi-synthesis hesperetin derivatives displayed stronger acetylcholinesterase inhibitory activity than hesperetin. Among them, derivative 1 has the best activity with an IC50 value of 43.50 μM. Conclusions: Four hesperetin derivatives were semi-synthesized and investigated their acetylcholinesterase inhibitory activity, some of which showed improvement in activity. Key words: Hesperetin, semi-synthesis, inhibit, enzyme, acetylcholinesterase

Investigations into the Chemistry of Some 1,6-Epithio and 1,6-Episeleno ß-D-Glucopyranoses

2000 ◽  
Vol 53 (5) ◽  
pp. 389 ◽  
Author(s):  
Brian W. Skelton ◽  
Robert V. Stick ◽  
D. Matthew G. Tilbrook ◽  
Allan H. White ◽  
Spencer J. Williams
Keyword(s):  
Crystal Structures ◽  
Oxidation Reactions ◽  
Derivatives Of ◽  
Glycosyl Donors

Derivatives of 1,6-dideoxy-1,6-epithio-β-D-glucopyranose have been shown to undergo oxidation reactions to afford the corresponding sulfoxides and sulfones. The sulfoxides participate in Pummerer reactions to afford the corresponding α-acetoxy sulfides which were then oxidized further. None of the sulfoxides, sulfones or α-acetoxy sulfides prepared were particularly efficient glycosyl donors. Also presented are crystal structures of 1,6-dideoxy-1,6-epithio-β-D-glucopyranose S,S-dioxide and 1,6-dideoxy-1,6-episeleno-β-D-glucopyranose, interesting analogues of 1,6-anhydro-β-D-glucopyranose.

Effets des sels de terres rares sur quelques phosphates dérivés des metabolites de la glycolyse

1991 ◽  
Vol 69 (8) ◽  
pp. 1281-1287 ◽  
Author(s):  
Claude Rabiller ◽  
Philippe Eymard ◽  
Mahmoud Mesbahi
Keyword(s):  
Nmr Spectroscopy ◽  
Key Words ◽  
Fermentation Process ◽  
Chemical Shifts ◽  
Deuterium Nmr ◽  
Sugar Fermentation ◽  
Phosphoglyceric Acid ◽  
Spectroscopy Studies ◽  
Sugar Derivatives ◽  
Derivatives Of

Phosphate derivatives of glucose and fructose are well-known intermediates in sugar fermentation. Proton and deuterium NMR spectroscopy studies of the fermentation process provide information about proton (deuteron) transfers that are likely to occur in such biotransformations. In this paper we describe the influence of complexation of those metabolites with praseodymium trichloride and of pH on their proton NMR chemical shifts. We determine the conditions under which all the protons of both the α. and β forms of these cyclic sugars are separated. Glucose-1 phosphate was found to be the most suitable derivative for this type of study. Furthermore, comparing the behaviour of these compounds with 2-phosphoglyceric acid allows us to specify the exact conformation of the latter. Key words: phosphate sugar derivatives, NMR, LIS effects.

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