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Gluing term

When this isomeiization reaction is catalyzed by alkah, it is termed the Lobry de Bmyn-Alberda van Ekenstein reaction. By it, D-glucose, D-mannose, and D-fmctose can be interconverted. The isomerizations involve a common intermediate, the 1,2-enediol. In the Glu—Man—Fm interconversions... [Pg.482]

A composite material consists of flat, thin metal plates of uniform thickness glued one to another with a thin, epoxy-resin layer (also of uniform thickness) to form a multi-decker-sandwich structure. Young s modulus of the metal is Ej, that of the epoxy resin is E2 (where E2 < Ej) and the volume fraction of metal is Vj. Find the ratio of the maximum composite modulus to the minimum composite modulus in terms of Ej, E2 and V. Which value of gives the largest ratio ... [Pg.278]

The results supported the proposal of Glu-165 as the general base and suggested the novel possibility of neutral histidine acting as an acid, contrary to the expectation that His-95 was protonated [26,58]. The conclusion that the catalytic His-95 is neutral has been confinned by NMR spectroscopy [60]. The selection of neutral imidazole as the general acid catalyst has been discussed in terms of achieving a pX, balance with the weakly acidic intermediate. This avoids the thermodynamic trap that would result from a too stable enediol intermediate, produced by reaction with the more acidic imidazolium [58]. [Pg.228]

Sickle-cell anemia is the classic example of an inherited disease that is caused by a change in a protein s amino acid sequence. Linus Pauling proposed in 1949 that it was caused by a defect in the hemoglobin molecule he thus coined the term molecular disease. Seven years later Vernon Ingram showed that the disease was caused by a single mutation, a change in residue 6 of the P chain of hemoglobin from Glu to Val. [Pg.43]

In a biochemical context, the naming of aldoketoses as dehydro aldoses is widespread. Thus D-xy/o-hexopyranos-4-ulose would be termed 4-dehydro-D-glu-cose. This usage of dehydro can give rise to names which are stereochemically redundant, and should not be employed for naming derivatives. [Pg.80]

The amino acid sequence of our first aPNA (which we termed backbone 1 or bl) was designed based on this amphipathic hehx sequence (Fig. 5.3 B). Specifically, this aPNA backbone included hydrophobic amino acids (Ala and Aib), internal salt bridges (Glu-(aa)3-Lys-(aa)3-Glu), a macrodipole (Asp-(aa)i5-Lys), and an N-ace-tyl cap to favor a-helix formation. The C-termini of these aPNA modules end in a carboxamide function to preclude any potential intramolecular end effects. Each aPNA module incorporates five nucleobases for Watson-Crick base pairing to a target nucleic acid sequence. [Pg.199]

The N-terminal methionine is posttranslationally acetylated [86], Similar N-term-inal sequences were found in several other proteins that contain N-acetylmethionine as the N-terminal amino acid, suggesting that the signal for acetylation may be the Met-Asp or Met-Glu sequence [71],... [Pg.64]

As these acetals could be converted into the 4,6-O-ethylidene derivatives on treatment with acid, it was reasoned that use of a cyclic vinyl ether, namely, 3,4-dihydro-2H-pyran, might prevent this second process, thus leading to a more useful method of selective acetalation.338 An equimolar reaction with methyl a-D-glu-copyranoside for 4 days in N,N-dimethylformamide led to utilization of 88% of the glycoside, and the 6-(tetrahydropyran-2-yl) ether constituted —85% of the crude reaction-product. In contrast to the steric control apparent in this instance, reaction of 3,4-dihydro-2H-pyran with the axial and equatorial hydroxyl groups in dl-1,4,5,6-tetra-O-acetyl-mi/o-inositol was completely unselective,339 a fact that has been rationalized310 in terms of the probable mechanism of these reactions. [Pg.71]

In STP effluents, total extractable estrogens and conjugates have been detected at levels up to 1 /jg/L [9,11,26]. Despite the wide variability in terms of removal efficiency reported for different WWTPs, a general trend has been observed with respect to the identity of the compounds most frequently detected in WWTP effluents. Thus, of the various compounds most commonly monitored - namely, estradiol, its metabolites estriol and estrone, and the synthetic estrogen ethynylestradiol - estrone is the most ubiquitous both in WWTP effluents and in environmental waters in general, while the most potent estrogens estradiol and ethynylestradiol have only occasionally been detected [26,40-42]. As for the conjugates, the very few studies that have attempted their determination pointed out estrone sulfates as the most abundant, while glu-curonides are most often found below the limit of detection [26,36,38,39]. [Pg.13]

On treatment of tri-O-acetyl-D-glucal with chlorine and silver fluoride,198 all four possible isomers were formed tri-0-acetyl-2-chloro-2-deoxy-a-D-mannopyranosyl fluoride (16%), tri-0-acetyl-2-chloro-2-deoxy-/3-D-mannopyranosyl fluoride (16%), tri-0-acetyl-2-chloro-2-deoxy-a-D-glucopyranosyl fluoride (6%), and tri-O-acetyl-2-chloro-2-deoxy-/3-D-glucopyranosyl fluoride (62%). These product ratios differ significantly from those of the corresponding bromofluorination and iodofluorination reactions of tri-O -ace tyl-D-glucal,43,53 and this behavior has been discussed198 in terms of the differences observed between the addition of bromine (or iodine) and chlorine to tri-O-acetyl-D-glu-cal, and the nature of the chlorination reaction itself. [Pg.237]

The serious reactions of long-term therapy (greater than 2 wk) and the addition of occlusive dressings are reversible hypothalamic-pituitary-adrenal (HPA) axis suppression, manifestations of Cushing s syndrome, hyperglycemia, and glu-... [Pg.342]

This is the kinetic equation for a glued cycle. In the leading term, all the outgoing reactions A, 0 with rate constants k — ski give the same eigenvalue -sw (100). [Pg.173]

Brandley and Schnaar [140] immobilized a synthetic nonapeptide, Tyr- Ala-Val Thr-Gly Arg-Gly-Asp-Ser, on a polyacrylamide gel, which had been prepared by a ternary copolymerization of acrylamide, bisacrylamide and the acrylic ester of. V-hydroxysuccinimide. They reported that Balb/c 3T3 mouse fibroblast cells (in Hepes-buffered Dulbecco s modified Eagle medium) adhered readily to the peptide-derivatized surfaces, even in the absence of serum, although long-term cell growth required the presence of serum. It was noticed that reference nonapeptide. Tyr-Arg-Leu-Glu-Asp-Pro-Ala-Met-Trp, which has no RGD sequence, failed to promote cell-attachment. [Pg.37]

As noted previously, available therapies moderate the hyperglycemia of diabetes, but fail to completely normalize metabolism. The long-stand-hg elevation of blood glucose causes the chronic complications of diabetes—premature atherosclerosis, retinopathy, nephropathy, and neuropathy. Intensive treatment with insulin (see p. 339) delays the onset and slows the progression of these long-term complications. For example, the incidence of retinopathy decreases as control of blood glu-... [Pg.343]


See other pages where Gluing term is mentioned: [Pg.929]    [Pg.1086]    [Pg.1123]    [Pg.75]    [Pg.178]    [Pg.358]    [Pg.224]    [Pg.226]    [Pg.59]    [Pg.62]    [Pg.185]    [Pg.257]    [Pg.20]    [Pg.324]    [Pg.48]    [Pg.74]    [Pg.101]    [Pg.120]    [Pg.276]    [Pg.7]    [Pg.71]    [Pg.315]    [Pg.119]    [Pg.131]    [Pg.124]    [Pg.17]    [Pg.608]    [Pg.192]    [Pg.277]    [Pg.180]    [Pg.15]    [Pg.93]    [Pg.975]   


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Gluing

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