Anchor derivatives

Synthetic mimics of cell-surface receptors have been constructed using plasma membrane anchors derived from N -alkyl-3fi-cholesterylamine and related compounds (14). Synthetic receptors comprising protein and other binding motifs linked to this membrane anchor become incorporated rapidly into plasma membranes of mammalian cells. By constimtively cycling between the plasma membrane and the endosomes, cells treated with these compounds gain the capacity to endocytose cell-impermeable hgands. For example, the synthetic Fc receptor shown in Fig. 4 enables human cells that lack Fc receptors... 

I. C. Almeida and R. T. Gazzinelli, Proinflammatory activity of glycosylphosphatidylinositol anchors derived from Trypanosoma cruzi. structural and functional analyses,. /. Leukoc. Biol., 70 (2001) 467-477. 

Fig. 9. Structures of the various GPI anchors derived from experiments described in Section VI. The calculated masses include the C-terminal peptide, and can be directly correlated with the masses shown in Figure 5. Man, mannose Gal, galactose GalNAc, N-acetyl galactosamine GlcNH2, glucosamine Ino, inositol Sia, sialic acid. (Reproduced with permission from Stahl, N. et al. [1999]. Biochemistry 31, 5043-5053. Copyright American Chemical Society.)...

More recendy, OPH was targeted onto the surfiice of an E. coli and Moraxella sp. using an ice-nucleation protein (INP) anchor derived from Pseudomonas syringe (35,36). Ice-nucleation protein (INP), an outer membrane protein from Pseudomonas syringae, is conqiosed of three distinct domains an N-terminal domain (15%) containing three or four potential transmembrane spans, a C-terminal domain (4%), and a central domain conqiosed of repeating... 

The substituted iron carbonyls Fe(CO)4PPh3 and Fe(CO)3(PPh3)2 have also been examined as photocatalysts for hydrosilation however, the qualitative reactivity features were found to be similar to those of Fe(CO)s [74]. In addition the polymer anchored derivatives Fe(CO)4(PPh2-poly) and Fe(CO)3(PPh2-poly)2 (where PPh2-poly is the polystyrene bound diphenyl phosphine) proved to be effective photocatalysts for lx)th hydrosilation and hydrogenation [74]. Photocatalysis of alkene hydrosilation is also effected by metal carbonyl clusters [61]. 

Heidler P, Link A (2005) N-Acyl-N-alkyl-sulfonamide anchors derived from Kenner s safety-catch linker powerfid tools in bioor-ganic and medicinal chemistry. Bioorg Med Chem 13 585-599... 

THE cvcLOBUTADENE-TETRAHEDRANE SYSTEM. A related reaction is the photoisomerization of cyclobutadiene (CBD). It was found that unsubstituted CBD does not react in an argon matrix upon irradiation, while the tri-butyl substituted derivative forms the corresponding tetrahedrane [86,87]. These results may be understood on the basis of a conical intersection enclosed by the loop shown in Figure 37. The analogy with the butadiene loop (Fig. 13) is obvious. The two CBDs and the biradical shown in the figure are the three anchors in this system. With small substituents, the two lobes containing the lone electrons can be far... 

Protect glycine as its Boc derivative and anchor this to the solid support Remove the pro tecting group and treat with Boc protected phenylalanine and DCCI Remove the Boc group with HCl then treat with HBr in tnfluoroacetic acid to cleave Phe Gly from the solid support... 

Piping supports, guides, and anchors increase local stresses on the pipe wall at the point of attachment. These stresses derive from continuously acting loads owing to the weight of the piping system carried at these points (pipe, contents, insulation), the pressure in the pipe, and any other loads such... 

Polypeptide Synthesis and Analysis. Sihca or controUed-pore glass supports treated with (chloromethyl)phenylethyltrimethoxysilane [68128-25-6] or its derivatives are replacing chloromethylated styrene—divinylbenzene (Merrifield resin) as supports in polypeptide synthesis. The sdylated support reacts with the triethyl ammonium salt of a protected amino acid. Once the initial amino acid residue has been coupled to the support, a variety of peptide synthesis methods can be used (34). At the completion of synthesis, the anchored peptide is separated from the support with hydrogen bromide in acetic acid (see Protein engineering Proteins). 

Ascorbic acid (vitamin C) is one of the body s endogenous water-soluble antioxidants. Modifications on the ascorbic acid structure have led to some very interesting compounds, such as a novel series of 3-O-alkyl ascorbic-acid derivatives. They have been found to be inhibitors of lipid peroxidation (Nihro etal., 1991). This antioxidant activity is directly related to the lipophilicity of the alkyl chain, su esting that the lipid chain may anchor the antioxidant portion of the molecule in the membrane. 

Recently, Suzuki-type reactions in air and water have also been studied, first by Li and co-workers.117 They found that the Suzuki reaction proceeded smoothly in water under an atmosphere of air with either Pd(OAc)2 or Pd/C as catalyst (Eq. 6.36). Interestingly, the presence of phosphine ligands prevented the reaction. Subsequently, Suzuki-type reactions in air and water have been investigated under a variety of systems. These include the use of oxime-derived palladacycles118 and tuned catalysts (TunaCat).119 A preformed oxime-carbapalladacycle complex covalently anchored onto mercaptopropyl-modified silica is highly active (>99%) for the Suzuki reaction of p-chloroacetophenone and phenylboronic acid in water no leaching occurs and the same catalyst sample can be reused eight times without decreased activity.120... 

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