426
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El-hamid Ismail A, Abdel Aleem AAH, Abdel Bary H, El-Assaly S. Synthesis of 1-(2-naphthylsulfonyl)pyrazole-C-glycosides. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2002; 21:469-75. [PMID: 12442964 DOI: 10.1081/ncn-120014819] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
2-Naphthylsulfonylhydrazine was reacted with aromatic aldehydes or aldehydo sugars to give the corresponding hydrazones which undergo Michael addition reactions with malononitrile or ethyl cyanoacetate to form pyrazole derivatives.
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427
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Elgemeie GH, Heikel AFZ, Ahmed MA. A direct route to 2-(beta-D-ribofuranosylthio)pyridine glycosides. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2002; 21:411-6. [PMID: 12442958 DOI: 10.1081/ncn-120014813] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A novel synthesis of a new class of 2-(beta-D-ribofuranosylthio)pyridine glycosides utilizing the reactions of substituted pyridine-2(1H)-thiones and 1-O-acetyl-2,3,5-tri-O-benzoyl-D-ribofuranose as starting components is described.
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428
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Roy SC, Rana KK, Guin C. Short and stereoselective total synthesis of furano lignans (+/-)-dihydrosesamin, (+/-)-lariciresinol dimethyl ether, (+/-)-acuminatin methyl ether, (+/-)-sanshodiol methyl ether, (+/-)-lariciresinol, (+/-)-acuminatin, and (+/-)-lariciresinol monomethyl ether and furofuran lignans (+/-)-sesamin, (+/-)-eudesmin, (+/-)-piperitol methyl ether, (+/-)-pinoresinol, (+/-)-piperitol, and (+/-)-pinoresinol monomethyl ether by radical cyclization of epoxides using a transition-metal radical source. J Org Chem 2002; 67:3242-8. [PMID: 12003531 DOI: 10.1021/jo010857u] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Intramolecular radical cyclization of suitably substituted epoxy ethers 4a-g using bis(cyclopentadienyl)titanium(III) chloride as the radical source resulted in trisubstituted tetrahydrofurano lignans and 2,6-diaryl-3,7-dioxabicyclo[3.3.0]octane lignans depending on the reaction conditions. The titanium(III) species was prepared in situ from commercially available titanocene dichloride and activated zinc dust in THF. Upon radical cyclization followed by acidic workup, epoxy olefinic ethers 4a-g afforded furano lignans dihydrosesamin 1a, lariciresinol dimethyl ether 1b, acuminatin methyl ether 1e, and sanshodiol methyl ether 1g directly and lariciresinol 1h, acuminatin 1i, and lariciresinol monomethyl ether 1j after removal of the benzyl protecting group by controlled hydrogenolysis of the corresponding cyclized products. The furofuran lignans sesamin 2a, eudesmin 2b, and piperitol methyl ether 2e were also prepared directly by using the same precursors 4a-f on radical cyclization followed by treatment with iodine and pinoresinol 2h, piperitol 2i, and pinoresinol monomethyl ether 2j after controlled hydrogenolysis of the benzyl protecting group of the corresponding cyclized products. Two naturally occurring acyclic lignans, secoisolariciresinol 5h and secoisolariciresinol dimethyl ether 5b, have also been prepared by exhaustive hydrogenolysis of 2h and 2b, respectively.
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429
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Vijayasaradhi S, Aidhen IS. Umpolung strategy for the synthesis of 2-deoxy-C-aryl glycosides: a serendipitous, efficient route for C-furanoside analogues. Org Lett 2002; 4:1739-42. [PMID: 12000287 DOI: 10.1021/ol025794w] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] 2-Deoxy-C-aryl glycosides are potential synthetic targets as they form a very vital moiety of several biologically active natural products. This paper describes a synthetic route using an umpolung strategy, which has not been explored till date. Our synthetic endeavor led to a versatile intermediate aryl ketone 10, which has paved the way for two important classes of C-glycosides, viz., C-alkyl furanosides 12 and methyl 2-deoxy-C-aryl pyranosides 14.
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430
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Abstract
[reaction: see text]. A novel approach to simple C-glycosides is reported. Reductive ring opening of 1,2-anhydro sugars with titanocene(III) chloride produces an anomeric radical that can be trapped with a variety of agents. The reaction stereospecifically affords alpha-glycosides and produces a free C-2 hydroxyl group allowing for further elaboration.
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431
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Caliş I, Tasdemir D, Ireland CM, Sticher O. Lucidin type anthraquinone glycosides from Putoria calabrica. Chem Pharm Bull (Tokyo) 2002; 50:701-2. [PMID: 12036036 DOI: 10.1248/cpb.50.701] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Two new lucidin type anthraquinone glycosides, putorinoside A (1) and putorinoside B (2) were isolated from Putoria calabrica, in addition to two known anthraquinone glycosides, lucidin 3-O-beta-glucopyranoside (3) and lucidin 3-O-primeveroside (4). Based on spectroscopic data, putorinosides A and B were identified as 2-hydroxymethyl-1-methoxy-3,5,6-trihydroxyanthraquinone 3-O-beta-glucopyranoside and 2-hydroxymethyl-1-methoxy-3,6-dihydroxyanthraquinone 3-O-beta-glucopyranoside, respectively.
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432
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Abstract
A general method for the synthesis of C-glycosyl amino acids is described here. The stereoisomerically pure tyrosine analogues alpha-L-4 and beta-L-6 are prepared in reasonable overall yields from allyl derivatives 10 and 11. The key step is a benzannulation procedure which is employed in the creation of the aromatic ring that bears the amino acid function.
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433
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Fraser-Reid B, Lopez JC, Radhakrishnan KV, Mach M, Schlueter U, Gomez AM, Uriel C. Unexpected role of O-2 "protecting" groups of glycosyl donors in mediating regioselective glycosidation. J Am Chem Soc 2002; 124:3198-9. [PMID: 11916390 DOI: 10.1021/ja012383m] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Glycosidation of several vicinal diols reveals that exquisite regioselectivity can be achieved by using 2-O-benzoyl n-pentenyl glycoside donors and/or their cyclic 1,2-ortho ester counterparts. The regioselective preferences for both are the same, although ratios and yields may differ. In stark contrast, glycosidation of the diols with the corresponding 2-O-benzylated donors gives poor, if any, regioselectivity.
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434
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Okuyama M, Mori H, Watanabe K, Kimura A, Chiba S. Alpha-glucosidase mutant catalyzes "alpha-glycosynthase"-type reaction. Biosci Biotechnol Biochem 2002; 66:928-33. [PMID: 12036080 DOI: 10.1271/bbb.66.928] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Replacement of the catalytic nucleophile Asp481 by glycine in Schizosaccharomyces pombe alpha-glucosidase eliminated the hydrolytic activity. The mutant enzyme (D481G) was found to catalyze the formation of an alpha-glucosidic linkage from beta-glucosyl fluoride and 4-nitrophenyl (PNP) alpha-glucoside to produce two kinds of PNP alpha-diglucosides, alpha-isomaltoside and alpha-maltoside. The two products were not hydrolyzed by D481G, giving 41 and 29% yields of PNP alpha-isomaltoside and alpha-maltoside, respectively. PNP monoglycosides, such as alpha-xyloside, alpha-mannoside, or beta-glucoside, acted as the substrate, but PNP alpha-galactoside and maltose could not. No detectable product was observed in the combination of alpha-glucosyl fluoride and PNP alpha-glucoside. This study is the first report on an "alpha-glycosynthase"-type reaction to form an alpha-glycosidic linkage.
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435
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Abstract
[reaction: see text] A six-step route for de novo synthesis of C-aryl glycosides based on cycloaddition of an aryl nitrile oxide with 4-pentyn-2-ol has been developed.
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436
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Srinivas O, Mitra N, Surolia A, Jayaraman N. Photoswitchable multivalent sugar ligands: synthesis, isomerization, and lectin binding studies of azobenzene-glycopyranoside derivatives. J Am Chem Soc 2002; 124:2124-5. [PMID: 11878960 DOI: 10.1021/ja0173066] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Coating of azobenzene chromophore with multivalent sugar ligands has been accomplished. Such sugar coating allows the study of the isomerization properties of this chromophore in aqueous solutions. The predominantly cis-isomer-containing photostationary state (PS) mixture of these azobenzene derivatives is found to be stable for hours. The rate constants for their isomerization, as well as the Arrhenius activation energies, are determined experimentally. An assessment of the lectin binding properties of the lactoside bearing isomeric azobenzene derivatives, by isothermal calorimetric methods, reveals the existence of an unusual cooperativity in their binding to lectin peanut agglutinin. Thermodynamic parameters evaluated for the trans and the PS mixture are discussed, in detail, for the lactoside bearing bivalent azobenzene derivative.
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437
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Shao H, Wang Z, Lacroix E, Wu SH, Jennings HJ, Zou W. Novel zinc (II)-mediated epimerization of 2'-carbonylalkyl-alpha-C-glycopyranosides to their beta-anomers. J Am Chem Soc 2002; 124:2130-1. [PMID: 11878963 DOI: 10.1021/ja017430p] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
2'-Aldehydes and 2'-ketones of alpha-C-glycosides, including the gluco-, galacto-, and manno- series, were epimerized exclusively to their beta-anomers in good-to-excellent yields under basic conditions and in the presence of zinc acetate. The beta-stereoselectivity is independent of the neighboring group at 2-O-substitution of sugar substrates. Therefore, this provides a particularly useful method for the preparation of manno-beta-C-glycosides. The epimerization is likely initiated by the formation of Zn-enolate that is stabilized by intramolecular chelation to the pyranose ring-oxygen to form a syn chair-boat structure. Due to the activation generated by the Zn-O coordination, fission of the C1-O bond occurs, leading to opening of the pyranose ring, which is spontaneously followed by a change in conformation. The more stable anti chair-boat transition state is favored, and the subsequent hetero-intramolecular Michael addition results in the formation of beta-C-glycoside in a ring-closure step.
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438
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Schwörer R, Schmidt RR. Efficient sialyltransferase inhibitors based on glycosides of N-acetylglucosamine. J Am Chem Soc 2002; 124:1632-7. [PMID: 11853437 DOI: 10.1021/ja017370n] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
D-Glucosamine was transformed into phenyl and 2-benzoyloxyethyl N-acetylglucosamine beta-glycosides 6a and 6b, respectively. Transformation of 6a,b into 6-O-unprotected N-acetylglucosamine derivatives 9a,b permitted the generation of an aldehyde group in the 6-position. Treatment of these intermediates with base afforded unsaturated aldehyde derivatives 10a,b, which are structural mimics of 2,3-dehydroneuraminic acid. H-Phosphonate addition to the aldehyde group and attachment of the cytidine monophosphate residue to the generated hydroxy group gave fully protected transition state analogues of cytidine monophosphate-N-acetylneuraminic acid 14a,b. Liberation of the unprotected compounds 1ah,l and 1bh,l led to excellent inhibitors of alpha(2-6)-sialyltransferase from rat liver. Variation of the protective group cleavage procedure for 14a,b led to formal loss of phosphate, thus resulting in diene derivatives (E)-/(Z)-2a,b, which also exhibited inhibitory properties.
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439
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Berger M, Luzzi SD, Henry AA, Romesberg FE. Stability and selectivity of unnatural DNA with five-membered-ring nucleobase analogues. J Am Chem Soc 2002; 124:1222-6. [PMID: 11841290 DOI: 10.1021/ja012090t] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In an effort to develop an orthogonal third base pair for the storage of genetic information, thiophene and furan heterocycles have been examined as nucleobase analogues. The stability of the unnatural bases was evaluated in duplex DNA paired opposite other unnatural bases as well as opposite the natural bases. Several unnatural base pairs are identified that are both reasonably stable and strongly selective against mispairing with native bases. These results expand the potential nucleobase analogues with which the genetic alphabet may be expanded to include five-membered-ring heterocycles.
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440
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Abdel-Rahman AAH, El Ashry ESH, Schmidt RR. Efficient intramolecular beta-mannoside formation using m-xylylene and isophthaloyl derivatives as rigid spacers. Carbohydr Res 2002; 337:195-206. [PMID: 11844489 DOI: 10.1016/s0008-6215(01)00306-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A series of mannosyl donors linked via position 2 to an m-xylylene or an isophthaloyl spacer which was connected to the position 6 of a glucoside acceptor afforded, via intramolecular glycosylation, the corresponding disaccharides with high beta anomeric ratio.
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441
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Guindon Y, Gagnon M, Thumin I, Chapdelaine D, Jung G, Guérin B. Synthesis of N-glycosides. An alternative approach based on diastereoselective base coupling and S(N)2 cyclization. Org Lett 2002; 4:241-4. [PMID: 11796060 DOI: 10.1021/ol016991i] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Acyclic diastereoselection is achieved for the formation of thioaminyl acetals. The highly intramolecular stereocontrolled S(N)2 displacement of the thioaminyls allows for the formation of cyclic nucleoside derivatives. This versatile approach may provide easy access to a large variety of N-glycosides.
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442
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Ishii K, Kubo H, Yamasaki R. Synthesis of alpha-lactosyl-(1-->3)-L-glycero-alpha-D-manno-heptopyranoside, a partial oligosaccharide structure expressed within the lipooligosaccharide produced by Neisseria gonorrhoeae strain 15253. Carbohydr Res 2002; 337:11-20. [PMID: 11755907 DOI: 10.1016/s0008-6215(01)00282-8] [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: 11/26/2022]
Abstract
The glycosyl donor, hepta-O-benzyl-beta-lactosyl trichloroacetimidate (4) was prepared by treating hepta-O-benzyl-lactose with trichloroacetonitrile in the presence of potassium carbonate. The acceptor, methyl 2-O-benzyl-4,6-O-benzylidene-7,8-dideoxy-alpha-D-manno-oct-7-enopyranoside (8) was synthesized by hydrolysis of a 3,4-butane diacetal of methyl L-glycero-alpha-D-manno-oct-enopyranoside and subsequent benzylidenation. Glycosidation of the donor 4 with the acceptor 8 in 1,4-dioxane using Me(3)SiOTf as a promoter for 1 h at room temperature gave methyl (2,3,4,6-tetra-O-benzyl-beta-D-galactopyranosyl)-(1-->4)-(2,3,6-tri-O-benzyl-alpha-D-glucopyranosyl)-(1-->3)-2-O-benzyl-4,6-O-benzylidene-7,8-dideoxy-alpha-D-manno-oct-7-enopyranoside (9) as a major product (59%). The oct-enopyranoside moiety of the trisaccharide 9 was converted to a heptopyranoside (80%) by oxidative cleavage with OsO(4)-NaIO(4) and subsequent reduction. Hydrogenolysis of the resulting trisaccharide and subsequent acetylation gave the peracetate of alpha-lactosyl-(1-->3)-Hep. Deacetylation of the peracetate afforded the title trisaccharide.
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443
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Casali M, Tarantini L, Riva S, Hunkova Z, Weignerova L, Kren V. Exploitation of a library of alpha-galactosidases for the synthesis of building blocks for glycopolymers. Biotechnol Bioeng 2002; 77:105-10. [PMID: 11745178 DOI: 10.1002/bit.10101] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
After screening a library of fungal alpha-galactosidases for the synthesis of functionalized alkyl alpha-D-galactopyranosides, four enzymes (isolated from Aspergillus terreus CCM55, Aspergillus commune CCM 2969, Penicillium vinaceum CCM 2384, or Penicillium brasilianum 2155) proved to be suitable for these biotransformations. The effect of different concentrations of alcohol on activity and stability of these enzymes was investigated. After optimization of the reaction conditions, three galactose derivatives (allyl, 2-nitroethyl and 2-(2',2',2'-trifluoroacetamido)-ethyl alpha-D-galactopyranoside, 1a, 3a, and 4a, respectively), suitable for subsequent chemical polymerization, were synthesized using either the "reverse hydrolysis" or the "transglycosylation" protocols.
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444
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Schweizer F, Inazu T. Chain extension of sugar delta-lactones with the enolate of tert-butyl bromoacetate and elaboration into functionalized C-ketosides, C-glycosides, and C-glucosyl glycines. Org Lett 2001; 3:4115-8. [PMID: 11735598 DOI: 10.1021/ol0102343] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[structure: see text] We describe the synthesis of a series of exocyclic sugar epoxides 1 prepared in a one-step procedure from sugar delta-lactones with the enolate of tert-butyl bromoacetate. Ring opening of the sugar oxiranes provides C-ketosides while reduction affords functionalized C-glycosides bearing an alpha-hydroxy ester moiety. The alpha-hydroxy ester can be converted into C-glucosyl glycine analogues 2.
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445
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Lin P, Lee CL, Sim MM. Synthesis of novel guanidinoglycoside: 2-glycosylamino 4,5-dihydro-6-pyrimidinone. J Org Chem 2001; 66:8243-7. [PMID: 11722234 DOI: 10.1021/jo015915q] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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446
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Hoffmann HM, Dunkel R, Mentzel M, Reuter H, Stark CB. The total synthesis of C-glycosides with completely resolved seven-carbon backbone polyol stereochemistry: stereochemical correlations and access to L-configured and other rare carbohydrates. Chemistry 2001; 7:4771-89. [PMID: 11763446 DOI: 10.1002/1521-3765(20011119)7:22<4771::aid-chem4771>3.0.co;2-j] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The de novo synthesis of a full set of hydroxymethyl C-glycosides from only two precursors is described. The seven-carbon target molecules contain five stereocentres and bridge the stereochemical gap between natural D-configured and non-natural L-configured series of hexoses. Key steps include hydroxylation, differential protection, stereoselective reduction and desymmetrization of 8-oxabicyclo[3.2.1]oct-6-enes. C-Terminus differentiation and C-terminus excision of the seven-carbon polyol backbone lead to hexoses, including those of the L-series. A stereochemical and genetic classification of C-glycosides is presented.
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447
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Kirschning A, Jesberger M, Schönberger A. The first polymer-assisted solution-phase synthesis of deoxyglycosides. Org Lett 2001; 3:3623-6. [PMID: 11700097 DOI: 10.1021/ol016545v] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction--see text] A glycosylation protocol for the synthesis of 2-deoxyglycosides has been developed which is based on the use of polymer-bound reagents. Glycals are transformed into 2-iodoglycosyl acetates using polymer-bound bis(acetoxy)iodate(I) complex (1). Activation of the anomeric center is achieved by employing polymer-bound silyl triflate (2). In the presence of different glycosyl acceptors, 2-deoxy-2-iodoglycosides are generated in very good yields. Furthermore, it is shown that this method can be embedded in multistep sequences toward glycosylated testosterone and rhodinosyl-olivosyl-olivoside.
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448
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Bravo F, Kassou M, Díaz Y, Castillón S. Synthesis of erythro and threo furanoid glycals from 1- and 2-phenylselenenyl-carbohydrate derivatives. Carbohydr Res 2001; 336:83-97. [PMID: 11689179 DOI: 10.1016/s0008-6215(01)00256-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Differently protected erythro and threo furanoid glycals were synthesized by selenoxide elimination when phenyl 1-selenoglycosides were treated in oxidizing conditions (tBuOOH, Ti(O(i)Pr)(4), Et(2)(i)PrN). The phenyl 1-selenoglycosides were obtained from methyl 2-deoxy-D-erythro-pentofuranoside by protection of the primary hydroxyl or both hydroxyls and further reaction with PhSeH in the presence of BF(3).Et(2)O. Erythro and threo furanoid glycals were also prepared by treating 2-deoxy-2-phenylselenenyl-1,4-anhydrocyclitols under similar conditions. The 2-deoxy-2-phenylselenenyl-1,4-anhydrocyclitols were obtained from 4-pentene-1,2,3-triols by a 5-endo selenium electrophilic induced cyclization.
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449
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Pachamuthu K, Vankar YD. Ceric ammonium nitrate-catalyzed tetrahydropyranylation of alcohols and synthesis of 2-deoxy-o-glycosides. J Org Chem 2001; 66:7511-3. [PMID: 11681969 DOI: 10.1021/jo0103322] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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450
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Zemliakov AE, Tsikalov VV, Kur'ianov VO, Chirva VI, Bovin NV. [Synthesis of N-acetylmuramoyl-L-alanyl-D-isoglutamine beta-aryl glycosides]. BIOORGANICHESKAIA KHIMIIA 2001; 27:439-43. [PMID: 11811066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Synthesis of N-acetylmuramyl-L-alanyl-D-isoglutamine phenyl and naphthyl-2 beta-glycosides, novel muramyl dipeptide derivatives with phenolic aglycones, was reported. The starting N-glucosamine aryl glycosides were obtained by glycosylation of phenols with peracetylated alpha-glucosaminyl chloride under the conditions of phase-transfer catalysis and used for the synthesis of 4,6-O-isopropylidene-N-acetylmyramic acid aryl beta-glycosides. Condensation of these derivatives with a dipeptide and subsequent deprotection resulted in the target glycopeptides.
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