N activity

Aktivienmgs-energie, /. energy of activation, mittel, n. activating agent, activator, -warme, /. heat of activation. zahl, /. activation number. 

Belebtschlamm, m, activated sludge. Belebungsmittel, n. activator restorative freshener. 

Filtered broth was passed at 2.5 ml/min through a resin column (2.5 cm diameter, 28 cm length) packed with 150 ml of ion exchange resin Amberlite IRC-50 sodium type (Rohm and Haas Co., U.S.A.). The column was washed with water, eluted with 0.5 N HCI at a flow rate 1.3 ml/min. The eluates were fractionated each 10 ml and tuberactinomycin-N activity was found at fractions No. 45-63 obsarved by ultraviolet absorption method and bioassay. 

These results have been fit to experimental data obtained for the reaction between a diisocyanate and a trifunctional polyester polyol, catalyzed by dibutyltindilaurate, in our laboratory RIM machine (Figure 2). No phase separation occurs during this reaction. Reaction order, n, activation energy, Ea, and the preexponential factor. A, were taken as adjustable parameters to fit adiabatic temperature rise data. Typical comparison between the experimental and numerical results are shown in Figure 7. The fit is quite satisfactory and gives reasonable values for the fit parameters. Figure 8 shows how fractional conversion of diisocyanate is predicted to vary as a function of time at the centerline and at the mold wall (remember that molecular diffusion has been assumed to be negligible). 

The Wacker Reaction and Related Oxidations. An important industrial process based on Pd-alkene complexes is the Wacker reaction, a catalytic method for conversion of ethene to acetaldehyde. The first step is addition of water to the Pd(n)-activated alkene. The addition intermediate undergoes the characteristic elimination of Pd(0) and H+ to generate the enol of acetaldehyde. 

Kl. Kalter, E. S., Daha, M. R Ten Cate, J. W Verhoef, J., and Bouma, B. N., Activation and inhibition of Hageman factor-dependent pathways and the complement system in uncomplicated bacteremia or bacterial shock. J. Infect. Dis. 151,1019-1027 (1985). 

Benitez-King, G., Rios, A., Martinez, A. Anton-Tay, F. (1996). In vitro inhibition of Ca2+/calmodulin-dependent kinase n activity by melatonin. Biochim. Biophys. Acta 1290, 191-6. 

The diffusion-reaction problem in the more general case occurs in a system containing n — 1 inactivated enzyme layers adjacent to the electrode surface on top of which N — n active layers have been deposited. Table 6.9 lists the equations that govern the fluxes of the two forms of the cosubstrate in such systems. 

TABLE 6.9. Fluxes Equations in an Enzyme Film Containing n 1 Inactive and N — n Active Layers... 

B. j. Berne, n Activated Barrier Crossing, Ed. by G. R. Fleming and P. Haggi, World Scientific, Singapore, 1993. 

Xylanase II was subjected to cation exchange chromatography with a 20-mm i.d., 700-mm long CM-Trisacryl column eluted with 0.8 mL/min of 0.025M sodium acetate buffer at pH 4.5, with a 0-0.2M sodium chloride gradient. Only one protein peak eluted from the column it contained all the Xylanase n activity. This material appeared... 

In an MCSCF calculation, not only the coefficients of the multiple configurations in the MC wave function, but also the orbitals in them, are simultaneously optimized. An (n/m)MCSCF calculation, in which the n active electrons and m active orbitals are chosen in the manner described in the preceding paragraph, is called a complete active space (CAS)SCF calculation. ... 

When the guest used is p-nitrophenylcholine carbonate (PNPCC) the Lewis acid zinc(n) activates the well-positioned carbonyl group in the P PCC Zn-cavitand towards reactions with external nucleophiles. The energy minimized structure of the PNPCC Zn-cavitand complex shows that cation-n interactions and C —O -Zn coordination bond occurs simultaneously. 

V. Bencomo and P. Sinay, Synthesis of M and N active glycopeptides. Part of the N-terminal region of human glycophorin A, Glycoconjugate J. 1 5 (1984). 

The activation for coupling by this method can be carried out either at the C-terminus (C-activation, for examples see Table 1) or at the N-terminus (N-activation, for examples see Table 2) of the corresponding components. The method of use of these compounds com-... 

C-Activated esters 6 are prepared by reacting hydrazides 4 with aryl chloroformates 5 (X=Q) or carbonic diesters 5 (X=OAr),M whereas N-activated esters 9 are obtained by reaction of the free amino group of N-terminal amino acid 7 or azaamino acid residues with the same reagents. 

Scheme 4 Generation and Coupling To Give Azapeptides via C- and N-Activated Esters16 812 14 21 291...

Solid-phase techniques can be applied to the N-activated esters.16 In the activated ester method, 4-nitrophenyl, 12 21-27 2,4-dinitrophenyl, 614 28 2,4,5-trichlorophenyl, 29 and penta-fluorophenyl 8 esters can be used, the amide bonds being formed with aminolytic release of the corresponding phenol (Scheme 4). For example, the use of pentafluorophenyl esters in the synthesis of pure azapeptides (named azatides for the first time) proved to be advantageous. 8 ... 

Like N-activated esters, N-activated azolides can be used in azapeptide synthesis. These include imidazolides[30 33] and 1,2,4-triazolidesJ34 These intermediates 14 can be synthesized by addition of the corresponding heterocycle 10 to a-isocyanato carboxylates Ilf30 31 or from the amino component 12 and l,T-carbonyldiimidazole (13).[32 33]... 

Their potential in azapeptide synthesis is similar to that of the N-activated esters or isocyanates as they react readily with hydrazides 15 to give the azapeptides 16 with release of imidazole or 1,2,4-triazole as shown in the general Scheme 5 and in an illustrative example (Scheme 6)J32 ... 

The isocyanate reaction pathway seems to have no major advantage over the other methods with N-activation (vide supra), since it implies an additional reaction step and the isocyanates react directly with hydrazides giving azapeptides. Advantages may be the easier handling of the solid and stable TV-azolides in comparison to the liquid, toxic, and relatively unstable isocyanates. 

In the only application of this method via N-activation, use of an TV-(chloroformyl)-proline ester leads to the AzAla analogue of the powerful antihypertensive agent enalapril with comparable biological activity/36 ... 

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