195136-66-4Relevant articles and documents
8-FLUORO-4-ALKYLUMBELLIFERYL ALPHA-D-GLUCOPYRANOSIDE, BIOLOGICAL STERILIZATION INDICATOR INCLUDING THE SAME AND ITS USE IN A METHOD OF DETERMINING EFFICACY OF A STERILIZATION PROCESS
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, (2021/04/02)
A self-contained biological sterilization indicator comprises: a housing; bacterial spores comprising, and/or capable of producing, an enzyme capable of catalyzing cleavage of an enzyme substrate; and a frangible container containing a composition, wherein the composition comprises the enzyme substrate, wherein if the frangible container is broken the composition will contact the bacterial spores to form a mixture having an initial pH in the range from 6.0 to 9.0. The enzyme substrate comprises a fluorinated 4'-alkylumbelliferyl α-D-glucopyranoside represented by the structural formula (I), wherein R is an alkyl group having from 1 to 12 carbon atoms. A biological sterilization indicator comprising a kit containing isolated components comprising (i) bacterial spores comprising, and/or capable of producing, an enzyme capable of catalyzing cleavage of the enzyme substrate and a method of assessing efficacy of a sterilization process are also disclosed.
Turnover Is rate-limited by deglycosylation for micromonospora viridifaciens sialidase-catalyzed hydrolyses: Conformational implications for the Michaelis complex
Chan, Jefferson,Lu, April,Bennet, Andrew J.
, p. 2989 - 2997 (2011/04/25)
A panel of seven isotopically substituted sialoside natural substrate analogues based on the core structure 7-(5-acetamido-3,5-dideoxy-d-glycero- α-d-galacto-non-2-ulopyranosylonic acid)-(2→6)-β-d- galactopyranosyloxy)-8-fluoro-4-methylcoumarin (1, Neu5Acα2,6GalβFMU) have been synthesized and used to probe the rate-limiting step for turnover by the M. viridifaciens sialidase. The derived kinetic isotope effects (KIEs) on kcat for the ring oxygen (18V), leaving group oxygen (18V), anomeric carbon (13V), C3-carbon (13V), C3-R deuterium (DVR), C3-S deuterium (DV S), and C3-dideuterium (D2V) are 0.986 ± 0.003, 1.003 ± 0.005, 1.021 ± 0.006, 1.001 ± 0.008, 1.029 ± 0.007, 0.891 ± 0.008, and 0.890 ± 0.006, respectively. The solvent deuterium KIE (D2OV) for the sialidase-catalyzed hydrolysis of 1 is 1.585 ± 0.004. In addition, a linear proton inventory was measured for the rate of hydrolysis, under saturating condition, as a function of n, the fraction of deuterium in the solvent. These KIEs are compatible with rate-determining cleavage of the enzymatic tyrosinyl β-sialoside intermediate. Moreover, the secondary deuterium KIEs are consistent with the accumulating Michaelis complex in which the sialosyl ring of the carbohydrate substrate is in a 6S2 skew boat conformation. These KIE measurements are also consistent with the rate-determining deglycosylation reaction occurring via an exploded transition state in which synchronous charge delocalization is occurring onto the ring oxygen atom. Finally, the proton inventory and the magnitude of the solvent KIE are consistent with deglycosylation involving general acid-catalyzed protonation of the departing tyrosine residue rather than general base-assisted attack of the nucleophilic water.
NOVEL TUBULIN POLYMERISATION INHIBITORS
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Page/Page column 90, (2008/06/13)
The present invention relates to compounds of general formula (I) as tublin polymerisation inhibitors and methods for preparing such compounds.
