51
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Memmi A, Granet R, Gahbiche MA, Fekih A, Bakhrouf A, Krausz P. Fatty esters of cellulose from olive pomace and barley bran: Improved mechanical properties by metathesis crosslinking. J Appl Polym Sci 2006. [DOI: 10.1002/app.23976] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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52
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Hadj-Bouazza A, Zerrouki R, Krausz P, Laumond G, Aubertin AM, Champavier Y. New acyclonucleosides: synthesis and anti-HIV activity. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 24:1249-63. [PMID: 16270666 DOI: 10.1081/ncn-200067423] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The synthesis of new acyclic nucleosides is described. These syntheses were accomplished by various methods: glycosylation, selective or total deprotection, oxidation/reduction, chlorination or azidation of hydroxyl groups. The compounds were characterized with NMR, mass and IR spectroscopy. Antiviral properties of these compounds were evaluated on HIV-1 infected cell lines.
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53
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Mazeau K, Moine C, Krausz P, Gloaguen V. Conformational analysis of xylan chains. Carbohydr Res 2005; 340:2752-60. [PMID: 16288999 DOI: 10.1016/j.carres.2005.09.023] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2005] [Revised: 09/27/2005] [Accepted: 09/29/2005] [Indexed: 12/01/2022]
Abstract
The present study provides a theoretical description of the different levels of structural organization that characterize the xylan polysaccharide in its native and hydrophobic lauroyl esterified forms. The goal of this study was to ascertain the role played by the hydroxyl or lauroyl side groups on the conformational flexibility of the xylan chain backbone. The results reported provide a detailed description of the low-energy conformers of the dimer segments, a complete characterization of the helical structures, an insight into the disordered state of the polysaccharide chains and an estimation of the cohesion of the amorphous solids. Esterification of xylan hydroxyl groups by lauric acid has a large effect on the conformational properties of the glycosidic bonds linking two repeat units. Both the location and the relative energies of the low energy areas of the potential energy surfaces strongly differ: extended and coiled conformations are preferred for the native and hydrophobic forms, respectively. Consequently, the predicted unperturbed polymer chain extension strongly depends on the structure, predicted Lp of the native xylan of 35 A compares favourably well with the experimental ones, this characteristic dramatically decreases to 9A for the hydrophobically modified chain. Curiously, only extended 2(1) and left-handed 3(1) helical structures are calculated stable for both polymers. The estimated cohesive parameters of amorphous bulks reveal that inter-chain interactions are stronger for the xylan chain than that for modified one, the former being stabilized by hydrogen bonds whereas hydrophobic interactions play a determinant role for the latter.
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54
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Memmi A, Granet R, Champavier Y, Krausz P. A highly efficient, solvent-free and energy-effective method of cellulose acetylation. E-POLYMERS 2005. [DOI: 10.1515/epoly.2005.5.1.885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractAcetylation of cellulose by acetic anhydride was found to be catalysed quantitatively by iodine under solvent-free conditions at room temperature. Cellulose acetates were characterised by 1H NMR spectroscopy.
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55
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Grandtner G, Joly N, Cavrot JP, Granet R, Bandur G, Rusnac L, Martin P, Krausz P. Synthesis of fructooligosaccharide-based plastic films starting from inulin. E-POLYMERS 2005. [DOI: 10.1515/epoly.2005.5.1.531] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractIn this preliminary study, inulin, a fructooligosaccharide extracted from chicory roots, was converted into plastic films by acylation in homogeneous medium and under conventional heating, using methacryloyl and lauroyl chlorides as acylating reagents and N,N-dimethyl-4-aminopyridine as basic catalyst. Products were analyzed by FT-IR and 1H NMR spectroscopies to confirm their structures. A preliminary study of their thermal properties was also achieved.
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56
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Colombeau L, Zerrouki R, Krausz P, Champavier Y. Dinucleoside Analog Synthesis Via Microwave Activated Cross Coupling Metathesis. LETT ORG CHEM 2005. [DOI: 10.2174/157017805774296885] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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57
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Roy V, Zerrouki R, Krausz P. New dinucleoside analogues via cross-coupling metathesis. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 24:289-301. [PMID: 16021919 DOI: 10.1081/ncn-60595] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Synthesis of 3'-3', 5-5', and 3'-5' dimeric thymidine, linked by an olefinic chain between glycosidic moieties is described. Cross metathesis reaction of 3' or 5' O-allyl analogues of thymidine led to the expected 3'-3' and 5'-5' dimeric compounds, respectively. In order to obtain the 3'-5' dimer, 5'-O-allyl and 3'-O-allyl monomers were first linked by their free 3' OH and 5' OH groups through a glutaryl spacer; ring closing metathesis was then operated upon this temporary dimer, followed by glutaryl removal.
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58
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Roy V, Zerrouki R, Krausz P, Schmidt S, Aubertin AM. Synthesis and antiviral evaluation of D4T analogues with a spacer arm between glucidic and base moieties. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 23:1625-37. [PMID: 15620100 DOI: 10.1081/ncn-200031457] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The synthesis of a series of d4T analogues bearing an acyclic chains between the sugar and the base moities, is described. New compounds were obtained readily using microwave irradiation and selective deprotection of sugar part. The compounds were characterized by 1H NMR and IR spectroscopy. Antiviral (HIV-1) properties of these compounds were examined.
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59
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Roy V, Zerrouki R, Krausz P. New Dinucleoside Analogues via Cross-Coupling Metathesis. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005. [DOI: 10.1081/ncn-200060595] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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60
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Sol V, Branland P, Chaleix V, Granet R, Guilloton M, Lamarche F, Verneuil B, Krausz P. Amino porphyrins as photoinhibitors of Gram-positive and -negative bacteria. Bioorg Med Chem Lett 2005; 14:4207-11. [PMID: 15261271 DOI: 10.1016/j.bmcl.2004.06.016] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2004] [Revised: 05/31/2004] [Accepted: 06/08/2004] [Indexed: 11/20/2022]
Abstract
Twenty four aminoporphyrin derivatives have been tested in vitro for their antibacterial photoactivity against Escherichia coli and Staphylococcus aureus. Two of these compounds, bearing polyamine units, exhibited a significant activity especially against Gram-negative bacteria (E. coli).
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61
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Zerrouki R, Billard L, Granet R, Krausz P. Glycosylation reaction of unprotected sugars with hydroxyalkylthymine. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2005; 23:749-54. [PMID: 15281363 DOI: 10.1081/ncn-120039217] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Under mild conditions (Lewis acid/solvent/room temperature), the reaction of unprotected glucose, deoxyribose or xylose with hydroxylalkylthymine gives selectively nucleoside analogs with a spacer arm between sugar and base moiety. Experimental conditions (Lewis acid, solvent) for this new strategy leading to nucleoside analogs synthesis are discussed.
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62
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Martin‐Dupont F, Gloaguen V, Granet R, Guilloton M, Krausz P. Chemical Modifications of Douglas Fir Bark, a Lignocellulosic By‐product—Enhancement of Their Lead(II) Binding Capacities. SEP SCI TECHNOL 2005. [DOI: 10.1081/ss-120030777] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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63
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Joly N, Granet R, Branland P, Verneuil B, Krausz P. New methods for acylation of pure and sawdust-extracted cellulose by fatty acid derivatives—Thermal and mechanical analyses of cellulose-based plastic films. J Appl Polym Sci 2005. [DOI: 10.1002/app.21783] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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64
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Roy V, Colombeau L, Zerrouki R, Krausz P. One step selective 5′-O-allylation of thymidine using microwave or ultrasound activation. Carbohydr Res 2004; 339:1829-31. [PMID: 15220095 DOI: 10.1016/j.carres.2004.04.008] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2004] [Revised: 04/19/2004] [Accepted: 04/21/2004] [Indexed: 11/26/2022]
Abstract
An improved procedures for the synthesis of 5'-O-allylthymidine via one step selective allylation of thymidine using either ultrasound or microwave activation is described.
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Moine C, Gloaguen V, Gloaguen JM, Granet R, Krausz P. Chemical valorization of forest and agricultural by-products. Obtention, chemical characteristics, and mechanical behavior of a novel family of hydrophobic films. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART. B, PESTICIDES, FOOD CONTAMINANTS, AND AGRICULTURAL WASTES 2004; 39:627-640. [PMID: 15473642 DOI: 10.1081/pfc-200026884] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Esterification of hemicelluloses of the xylan family was performed in order to produce hydrophobic films. Acylation reactions were carried out with lauroyl chloride in the N,N-dimethylacetamide/lithium chloride homogeneous system using 4-dimethylaminopyridine as activator and were induced by microwave irradiation. In the experimental conditions used, 108 and 172% mass ratios were obtained for the dodecyl-grafted xylan and heteroxylan, respectively. The degrees of substitution (DS) were 1.3 (maximum 2) for xylan and 1.2 (maximum 2.1) for heteroxylan. These products were further characterized by FT-IR spectroscopy. The mechanical and thermomechanical behavior of this new family of hydrophobic films were analyzed and compared to those obtained from cellulose with a similar DS by the means of tensile tests. Our results indicate that the dodecyl-grafted xylan film presents the best rigidity-resistance to traction ratio.
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66
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Satgé C, Granet R, Verneuil B, Champavier Y, Krausz P. Synthesis and properties of new bolaform and macrocyclic galactose-based surfactants obtained by olefin metathesis. Carbohydr Res 2004; 339:1243-54. [PMID: 15113661 DOI: 10.1016/j.carres.2004.03.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2003] [Revised: 03/01/2004] [Accepted: 03/03/2004] [Indexed: 11/30/2022]
Abstract
A series of galactose-based surfactants with various structures likely to display new interesting properties were synthesized. Four monocatenary surfactants were elaborated by microwave-assisted galactosylation of undecanol or 10-undecenol. These compounds were slightly soluble in water. Their tensioactive properties were determined at 45 degrees C. Olefin metathesis was used to synthesize the two single-chain bolaforms from undec-10-enyl galactopyranosides; two pseudomacrocyclic bolaforms were prepared by grafting two carbamates at O-4 and O-4' sugar positions of the single-chain bolaforms. These four surfactants are insoluble in water and undergo monolayer compression. Cyclization of these bolaforms by olefin metathesis led to macrocyclic surfactant analogues of archaeobacterial membrane components.
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67
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Satgé C, Granet R, Verneuil B, Branland P, Krausz P. Synthesis and properties of biodegradable plastic films obtained by microwave-assisted cellulose acylation in homogeneous phase. CR CHIM 2004. [DOI: 10.1016/j.crci.2003.11.003] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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68
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Lautrette S, Granet R, Krausz P. A new method of solvent free O- and N-glycosylation using activated carbon fiber (ACF) as a promoter. Application to the synthesis of saponin and nucleoside analogues. Chem Commun (Camb) 2004:586-7. [PMID: 14973620 DOI: 10.1039/b315699k] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
By using activated carbon fiber (ACF) as solid acid promoter, we display a new system for solvent free O- and N-glycosylation, with a simple process which takes place in a drying oven; this method has been applied to the synthesis of sterol and triterpene O-glycosides (saponin analogues), as well as nucleoside analogues.
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69
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Gloaguen V, Ruiz G, Morvan H, Mouradi-Givernaud A, Maes E, Krausz P, Strecker G. The extracellular polysaccharide of Porphyridium sp.: an NMR study of lithium-resistant oligosaccharidic fragments. Carbohydr Res 2004; 339:97-103. [PMID: 14659675 DOI: 10.1016/j.carres.2003.09.020] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This study deals with the chemical characterization of an extracellular polysaccharide produced by the unicellular red alga Porphyridium sp. The sugar moiety of this polymer is composed of three neutral monosaccharides (Xyl, Glc, and Gal) and one uronic acid (GlcA). Proteins represent 5.5% of the dry weight of the polymer. Uronic degradation of this exopolysaccharide with lithium in ethylenediamine yielded two different oligosaccharides. The absolute configuration of the constitutive monosaccharides was chemically determined and revealed the presence of D-Xyl, D-Glc, D-, and L-Gal. The following oligosaccharide structures were established by NMR spectroscopy: [carbohydrate structure: see text].
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Joly N, Granet R, Krausz P. Olefin metathesis applied to cellulose derivatives?Synthesis, analysis, and properties of new crosslinked cellulose plastic films. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/pola.20519] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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71
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Chaleix V, Sol V, Huang YM, Guilloton M, Granet R, Blais J, Krausz P. RGD-Porphyrin Conjugates: Synthesis and Potential Application in Photodynamic Therapy. European J Org Chem 2003. [DOI: 10.1002/ejoc.200390208] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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72
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73
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Krausz P, Garnier F, Dubois JE. Photochemically induced olefin metathesis by transition metal complex. I. Intermediacy of pentacarbonylchlorotungsten. J Am Chem Soc 2002. [DOI: 10.1021/ja00835a044] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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74
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Martin-Dupont F, Gloaguen V, Granet R, Guilloton M, Morvan H, Krausz P. Heavy metal adsorption by crude coniferous barks: a modelling study. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2002; 37:1063-1073. [PMID: 12090280 DOI: 10.1081/ese-120004523] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Equilibria and mechanisms involved in the adsorption process of metal ions (Cr3+, Cu2+, Ni2+, Pb2+ and Zn2+) from aqueous solutions using coniferous barks as biosorbent substrate were investigated. Crude barks were used in this study since previous experiments showed a decreasing uptake for chemically treated barks in the considered granulometry. In our experimental conditions, the maximum binding capacity of barks followed the decreasing order Cr3+ > Cu2+ > Pb2+ > Ni2+ > Zn2+ whereas their general binding affinity decreased as: Pb2+ > Cr3+ > Ni2+ > Zn2+ > Cu2+. Adsorption isotherms at the optimal physicochemical conditions were established and the adsorption phenomenon was described by the non-competitive Langmuir adsorption model which fitted well the experimental data. An evaluation of adsorption capability was carried out using model parameters which were graphically determined. Models for removal of cations have been discussed; they represent efficient tools for predicting the behaviour of the biosorbents in metal ion adsorption systems.
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Sylvain I, Zerrouki R, Granet R, Huang YM, Lagorce JF, Guilloton M, Blais JC, Krausz P. Synthesis and biological evaluation of thioglycosylated porphyrins for an application in photodynamic therapy. Bioorg Med Chem 2002; 10:57-69. [PMID: 11738607 DOI: 10.1016/s0968-0896(01)00255-3] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The aim of this work is the synthesis of a new family of glycosylated porphyrins in which the sugar moieties are linked to the tetrapyrrole ring by a thioglycosidic bond. Two series have been designed. The first one corresponds to meso-aryl porphyrin derivatives. The second one has been obtained from protoporphyrin IX derivatization. Aryl-porphyrins were prepared from tristolyl o- and p-hydroxyporphyrins followed by bromoallylation and thioglycosylation with peracetylated S-glucose, mannose and galactose and deprotection. The other series has been synthesized from protoporphyrin IX dimethylester with a regioselective glycosylation of terminal alkenyl carbon. The UV-visible, NMR and MALDI mass spectra are presented. Photocytotoxicities of the synthesized compounds against K562 chronic leukaemia cell line has been evaluated.
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