5 research outputs found
Deprotometalation-iodolysis and computed CH acidity of 1,2,3- and 1,2,4-triazoles. Application to the synthesis of resveratrol analogues
International audience1-Aryl- and 2-aryl-1,2,3-triazoles were synthesized by N-arylation of the corresponding azoles using aryl iodides. The deprotometalations of 1-phenyl-1,2,3-triazole and -1,2,4-triazole were performed using a 2,2,6,6-tetramethylpiperidino-based mixed lithium-zinc combination and occurred at the most acidic site, affording by iodolysis the 5-substituted derivatives. Dideprotonation was noted from 1-(2-thienyl)-1,2,4-triazole by increasing the amount of base. From 2-phenyl-1,2,3-triazoles, and in particular from 2-(4-trifluoromethoxy)phenyl-1,2,3-triazole, reactions at the 4 position of the triazolyl, but also ortho to the triazolyl on the phenyl group, were observed. The results were analyzed with the help of the CH acidities of the substrates, determined in THF solution using the DFT B3LYP method. 4-Iodo-2-phenyl-1,2,3-triazole and 4-iodo-2-(2-iodophenyl)-1,2,3-triazole were next involved in Suzuki coupling reactions to furnish the corresponding 4-arylated and 4,2â-diarylated derivatives. When evaluated for biological activities, the latter (which are resveratrol analogues) showed moderate antibacterial activity and promising antiproliferative effect against MDA-MB-231 cell line
Study of the anti-bioadhesion activity of glass surfaces grafted with rare furanosidic carbohydrates
La biocontamination de surface par des microorganismes provoque dâimportantes consĂ©quences Ă©conomiques et sanitaires. Les diffĂ©rents moyens de prĂ©vention mis en place de nos jours utilisent des composĂ©s biocides nocifs pour lâenvironnement et participent Ă la recrudescence de lâantibiorĂ©sistance des organismes pathogĂšnes. Ces travaux de recherche Ă©tudient une approche alternative non-biocide et non-toxique. Elle consiste Ă inhiber lâadhĂ©sion microbienne en appliquant une couche de monofuranosides sur une surface. La conception des surfaces a dĂ©butĂ© par les synthĂšses glycosidiques des furanosides cibles Ă partir du D-Glucose, D-Galactose et D- Mannose. Des homologues pyranosidiques, connus pour leur activitĂ© antiadhĂ©sive, ont Ă©tĂ© rĂ©alisĂ©s afin de comparer lâintĂ©rĂȘt de la forme cyclique. Ces sucres ont ensuite Ă©tĂ© greffĂ©s par chimie click sur une surface de verre prĂ©fonctionnalisĂ©e et au travers dâun lien O-glycosidique ou S- glycosidique via un groupe triazole. Les surfaces rĂ©sultantes ont Ă©tĂ© caractĂ©risĂ©es Ă lâaide de la goniomĂ©trie et de la spectroscopie photoĂ©lectron par rayons X. Les Ă©tudes dâadhĂ©sion avec Pseudomonas aeruginosa ont rĂ©vĂ©lĂ© une activitĂ© anti-biodhĂ©sion des surfaces furanosidiques et pyranosidiques. Les interactions spĂ©cifiques et non-spĂ©cifiques ont Ă©tĂ© explorĂ©es grĂ ce Ă lâadhĂ©sion de mutants dĂ©ficiants en lectine et dâun modĂšle thermodynamique. Les rĂ©sultats ont conclu que lâactivitĂ© antiadhĂ©sive des monosaccharides Ă©tait davantage liĂ©e aux propriĂ©tĂ©s physicochimiques des sucres plutĂŽt quâĂ des interactions biologiques.Surface biocontamination from microorganisms leads to serious economic and health issues. Nowadays, biocide compounds are mostly used as prevention. Nonetheless, they are known to be toxic for environment and to participate in the rise of the antibiotic resistance of pathogens. These research works examine a non-biocide and non-toxic approach. It is based on the inhibition of the microbial adhesion with a monofuranoside-functionalized surface. The development of surfaces was started with the glycosidic synthesis of target furanosides from D-Glucose, D-Galactose and D-Mannose. In order to compare the interest of the cyclic form, pyranosidic homologues, known for their anti-adhesive activity, were also achieved. The modified glycosides were then grafted to a prefunctionalized glass surface linked through an O-glycosidic or S-glycosidic via a triazole group. The resulted surfaces were characterized using goniometry and X-ray photoelectron spectroscopy. The adhesion studies with Pseudomonas aeruginosa have shown an anti-bioadhesion activity with furanosidic and glycosidic surfaces. Specific and non-specific interactions were explored through lectin deficient mutant strains and a thermodynamic approach. The anti-bioadhesive activity was concluded to depent more on the carbohydrate physicochemical properties, rather than the biological interactions
Ătude de l'activitĂ© anti-bioadhĂ©sion de surfaces de verres greffĂ©es par des sucres furanosidiques rares
Surface biocontamination from microorganisms leads to serious economic and health issues. Nowadays, biocide compounds are mostly used as prevention. Nonetheless, they are known to be toxic for environment and to participate in the rise of the antibiotic resistance of pathogens. These research works examine a non-biocide and non-toxic approach. It is based on the inhibition of the microbial adhesion with a monofuranoside-functionalized surface. The development of surfaces was started with the glycosidic synthesis of target furanosides from D-Glucose, D-Galactose and D-Mannose. In order to compare the interest of the cyclic form, pyranosidic homologues, known for their anti-adhesive activity, were also achieved. The modified glycosides were then grafted to a prefunctionalized glass surface linked through an O-glycosidic or S-glycosidic via a triazole group. The resulted surfaces were characterized using goniometry and X-ray photoelectron spectroscopy. The adhesion studies with Pseudomonas aeruginosa have shown an anti-bioadhesion activity with furanosidic and glycosidic surfaces. Specific and non-specific interactions were explored through lectin deficient mutant strains and a thermodynamic approach. The anti-bioadhesive activity was concluded to depent more on the carbohydrate physicochemical properties, rather than the biological interactions.La biocontamination de surface par des microorganismes provoque dâimportantes consĂ©quences Ă©conomiques et sanitaires. Les diffĂ©rents moyens de prĂ©vention mis en place de nos jours utilisent des composĂ©s biocides nocifs pour lâenvironnement et participent Ă la recrudescence de lâantibiorĂ©sistance des organismes pathogĂšnes. Ces travaux de recherche Ă©tudient une approche alternative non-biocide et non-toxique. Elle consiste Ă inhiber lâadhĂ©sion microbienne en appliquant une couche de monofuranosides sur une surface. La conception des surfaces a dĂ©butĂ© par les synthĂšses glycosidiques des furanosides cibles Ă partir du D-Glucose, D-Galactose et D- Mannose. Des homologues pyranosidiques, connus pour leur activitĂ© antiadhĂ©sive, ont Ă©tĂ© rĂ©alisĂ©s afin de comparer lâintĂ©rĂȘt de la forme cyclique. Ces sucres ont ensuite Ă©tĂ© greffĂ©s par chimie click sur une surface de verre prĂ©fonctionnalisĂ©e et au travers dâun lien O-glycosidique ou S- glycosidique via un groupe triazole. Les surfaces rĂ©sultantes ont Ă©tĂ© caractĂ©risĂ©es Ă lâaide de la goniomĂ©trie et de la spectroscopie photoĂ©lectron par rayons X. Les Ă©tudes dâadhĂ©sion avec Pseudomonas aeruginosa ont rĂ©vĂ©lĂ© une activitĂ© anti-biodhĂ©sion des surfaces furanosidiques et pyranosidiques. Les interactions spĂ©cifiques et non-spĂ©cifiques ont Ă©tĂ© explorĂ©es grĂ ce Ă lâadhĂ©sion de mutants dĂ©ficiants en lectine et dâun modĂšle thermodynamique. Les rĂ©sultats ont conclu que lâactivitĂ© antiadhĂ©sive des monosaccharides Ă©tait davantage liĂ©e aux propriĂ©tĂ©s physicochimiques des sucres plutĂŽt quâĂ des interactions biologiques
Pseudomonas aeruginosa resistance of monosaccharide-functionalized glass surfaces
International audienc
ROMP-based Glycopolymers with High Affinity for Mannose-Binding Lectins
Well-defined, highly reactive poly(norbornenyl azlactone)s
of controlled
length (number-average degree of polymerization DPnÌ
= 10 to 1,000) were made by ring-opening
metathesis polymerization (ROMP) of pure exo-norbornenyl
azlactone. These were converted into glycopolymers using a facile
postpolymerization modification (PPM) strategy based on click aminolysis
of azlactone side groups by amino-functionalized glycosides. Pegylated
mannoside, heptyl-mannoside, and pegylated glucoside were used in
the PPM. Binding inhibition of the resulting glycopolymers was evaluated
against a lectin panel (Bc2L-A, FimH, langerin, DC-SIGN, ConA). Inhibition
profiles depended on the sugars and the degrees of polymerization.
Glycopolymers from pegylated-mannoside-functionalized polynorbornene,
with DPnÌ
= 100, showed strong binding inhibition,
with subnanomolar range inhibitory concentrations (IC50s). Polymers surpassed the inhibitory potential of their monovalent
analogues by four to five orders of magnitude thanks to a multivalent
(synergistic) effect. Sugar-functionalized poly(norbornenyl azlactone)s
are therefore promising tools to study multivalent carbohydrateâlectin
interactions and for applications against lectin-promoted bacterial/viral
binding to host cells