01469nas a2200193 4500008004100000022001400041245012800055210006900183260011000252300001400362490000600376520065800382100002201040700002701062700001901089700002201108700002001130856012501150 2011 eng d a1477-052000aFacile synthesis of unusual glycosyl carbamates and amino acid glycosides from propargyl 1,2-orthoesters as glycosyl donors0 aFacile synthesis of unusual glycosyl carbamates and amino acid g aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcMAR a5951-59590 v93 a

Propargyl 1,2-O-orthoesters are exploited for the synthesis of 1,2-trans O-glycosides of protected amino acids. N-Fmoc- and N-Cbz protected serine/threonine - benzyl/methyl esters reacted well with glucosyl-, galactosyl-, mannosyl- and lactosyl- derived propargyl 1,2-orthoesters affording respective 1,2-trans glycosides in good yields under AuBr(3)/4 angstrom MS Powder/CH(2)Cl(2)/rt. t-Boc serine derivative gave serine 1,2-orthoester and glycosyl carbamate. Optimized conditions enabled preparation of new glycosyl carbamates from N-Boc protected amines in a single step using gold catalysts and propargyl 1,2-orthoesters in excellent yields.

1 aShaikh, Ashif, Y.1 aSureshkumar, Gopalsamy1 aPati, Debasish1 aGupta, Sayam, Sen1 aHotha, Srinivas uhttps://library.ncl.res.in/content/facile-synthesis-unusual-glycosyl-carbamates-and-amino-acid-glycosides-propargyl-12-000975nas a2200193 4500008004100000022001400041245008800055210006900143260011000212300001400322490000700336520022300343100002100566700001800587700001700605700002000622700002200642856011700664 2011 eng d a1359-734500aFe(III) complex of biuret-amide based macrocyclic ligand as peroxidase enzyme mimic0 aFeIII complex of biuretamide based macrocyclic ligand as peroxid aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUN a8016-80180 v473 a

An Fe(III) complex of a biuret-amide based macrocyclic ligand that exhibits both excellent reactivity for the activation of H(2)O(2) and high stability, especially at low pH and high ionic strength, is reported.

1 aPanda, Chakadola1 aGhosh, Munmun1 aPanda, Tamas1 aBanerjee, Rahul1 aGupta, Sayam, Sen uhttps://library.ncl.res.in/content/feiii-complex-biuret-amide-based-macrocyclic-ligand-peroxidase-enzyme-mimic-001933nas a2200193 4500008004100000022001400041245010500055210006900160260007100229300001600300490000800316520117500324100001901499700002001518700002301538700003001561700002201591856012601613 2011 eng d a1932-744700aFunctionalization of SBA-15 mesoporous materials using ``thiol-ene click'' michael addition reaction0 aFunctionalization of SBA15 mesoporous materials using thiolene c a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP a17774-177810 v1153 a

Methacrylate-labeled SBA-15 has been successfully synthesized from calcined SBA-15 and commercially available 3-trichlorosilyl propylmethacrylate. This material undergoes efficient thiol-ene ``click reaction'' with a variety of both thiol and disulfide-containing substrates in aqueous and organic media. The products were thoroughly characterized by a variety of analytical techniques including multinuclear (C-13, Si-29) solid-state NMR, TG-DTA, and nitrogen adsorption desorption studies. Disulfide-containing substrates in which the TCEP-mediated reduction of the disulfide bond and its subsequent addition to the methacrylate group anchored in SBA-15 in one-pot were used to synthesize a silica-protein hybrid material composed of biotin-labeled SBA-15 and streptavidin. Electrochemically active material was synthesized from the reaction of ferrocene-containing thiol and the methacrylate-labeled SBA-15. The ease of synthesis for the methacrylate-labeled SBA-15 material together with its ability to undergo efficient chemoselective thiol-ene reaction would make it a very attractive platform for the development of covalently anchored enzymes and sensors.

1 aKumari, Sushma1 aMalvi, Bharmana1 aGanai, Anal, Kumar1 aPillai, Vijayamohanan, K.1 aGupta, Sayam, Sen uhttps://library.ncl.res.in/content/functionalization-sba-15-mesoporous-materials-using-thiol-ene-click-michael-addition-003121nas a2200253 4500008004100000022001400041245011400055210006900169260007100238300001600309490000600325520221300331653002102544653001702565653000802582653002102590653002502611100001902636700002002655700002102675700002002696700002202716856012902738 2014 eng d a1944-824400aFe-TAML encapsulated inside mesoporous silica nanoparticles as peroxidase mimic: femtomolar protein detection0 aFeTAML encapsulated inside mesoporous silica nanoparticles as pe a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcAUG a13866-138730 v63 a

Peroxidase, such as horseradish peroxidase (HRP), conjugated to antibodies are routinely used for the detection of proteins via an ELISA type assay in which a critical step is the catalytic signal amplification by the enzyme to generate a detectable signal. Synthesis of functional mimics of peroxidase enzyme that display catalytic activity which far exceeds the native enzyme is extremely important for the precise and accurate determination of very low quantities of proteins (fM and lower) that is necessary for early clinical diagnosis. Despite great advancements, analyzing proteins of very low abundance colorimetrically, a method that is most sought after since it requires no equipment for the analysis, still faces great challenges. Most reported HRP mimics that show catalytic activity greater than native enzyme (similar to 40-fold) are based on metal/metal-oxide nanoparticles such as Fe3O4. In this paper, we describe a second generation hybrid material developed by us in which approximately 25 000 alkyne tagged biuret modified Fetetraamido macrocyclic ligand (Fe-TAML), a very powerful small molecule synthetic HRP mimic, was covalently attached inside a 40 nm mesoporous silica nanopartide (MSN). Biuret-modified Fe-TAMLs represent one of the best small molecule functional mimics of the enzyme HRP with reaction rates in water close to the native enzyme and operational stability (pH, ionic strength) far exceeding the natural enzyme. The catalytic activity of this hybrid material is around 1000-fold higher than that of natural HRP and 100-fold higher than that of most metal/metal oxide nanoparticle based HRP mimics reported to date. We also show that using antibody conjugates of this hybrid material it is possible to detect and, most importantly, quantify femtomolar quantities of proteins colorimetrically in an ELISA type assay. This represents at least 10-fold higher sensitivity than other colorimetric protein assays that have been reported using metal/metal oxide nanoparticles as HRP mimic. Using a human IgG expressing cell line, we were able to demonstrate that the protein of interest human IgG could be detected from a mixture of interfering proteins in our assay.

10acolorimetrically10aimmuno assay10aMSN10aperoxidase mimic10asignal amplification1 aKumari, Sushma1 aDhar, Basab, B.1 aPanda, Chakadola1 aMeena, Abhishek1 aGupta, Sayam, Sen uhttps://library.ncl.res.in/content/fe-taml-encapsulated-inside-mesoporous-silica-nanoparticles-peroxidase-mimic-femtomolar-001414nas a2200229 4500008004100000022001400041245010000055210006900155260007100224300001400295490000800309520056500317100001800882700002200900700002100922700001800943700002600961700002600987700002001013700002201033856012901055 2014 eng d a0002-786300aFormation of a room temperature stable Fe-V(O) complex: reactivity toward unactivated C-H bonds0 aFormation of a room temperature stable FeVO complex reactivity t a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcJUL a9524-95270 v1363 a

An Fe-V(O) complex has been synthesized from equimolar solutions of (Et4N)(2)[Fe-III(Cl)(biuretamide)] and mCPBA in CH3CN at room temperature. The Fe-V(O) complex has been characterized by UV-vis, EPR, Mossbauer, and HRMS and shown to be capable of oxidizing a series of alkanes having C-H bond dissociation energies ranging from 99.3 kcal mol(-1) (cyclohexane) to 84.5 kcal mori (cumene). Linearity in the Bell-Evans-Polayni graph and the finding of a large kinetic isotope effect suggest that hydrogen abstraction is engaged the rate-determining step.

1 aGhosh, Munmun1 aSingh, Kundan, K.1 aPanda, Chakadola1 aWeitz, Andrew1 aHendrich, Michael, P.1 aCollins, Terrence, J.1 aDhar, Basab, B.1 aGupta, Sayam, Sen uhttps://library.ncl.res.in/content/formation-room-temperature-stable-fe-vo-complex-reactivity-toward-unactivated-c-h-bonds-0