5,p-Selectivity

Neurokinin effects are terrninated by proteolysis. In vitro acetylcholinesterase (ACE) and enkephalinase can hydrolyze substance P. However, there appears to be no clear evidence that either acetylcholinesterase or ACE limit the actions of released substance P. Enkephalinase inhibitors, eg, thiorphan, can augment substance P release or action in some systems but the distribution of enkephalinase in the brain does not precisely mirror that of substance P. There appears to be a substance P-selective enzyme in brain and spinal cord. 

It has been demonstrated that the P -selectivity is due to the para-substituents of these dmgs (96). In contrast, (-)-erythro-isoetharine (127), a bronchodilator, is 80 times more selective for receptors than for P ceptors. Isoetharine (97) contains an a-alkyl substituent, thus... 

Further, the step function 0(x(r) — x ) is replaced by the projection operator p selecting the states which evolve finally to the product valley at r -> oo,... 

LUCKETT, F. J., Engineering Design Basis for Plastics Products, HMSO, London (1981) Macdermott, c. p., Selecting Thermoplastics for Engineering Applications, Marcel Dekker, New York and Basel (1984)... 

Brasquet, C., Subrenat, E. and Le Cloirec, P., Selective adsorption on fibrous activated carbon of organics from aqueous solution Correlation between adsorption and moleeular strueture. Water Sci. Technol., 1997, 35(7), 251 259. 

Rasor, J. P., Selecting a Holiday Detector , A Collection of Papers on Underground Corrosion (Ed. George B. McComb, NACE), Vol. 4, 1st edn (1960)... 

Rearrange d = MP/RT into M = dRT/P, select a value of R with appropriate units, and substitute the data. 

Berthelot et al. have already reported that the reaction of aromatic amines with tetrabutylammonium tribromide (TBA Br3) in chloroform gave p-selective bromo-substituted aromatic amines (ref. 10). We also carried out the bromination of... 

This work is in its early stages, but it is already clear that a significant improvement in P-selectivity can be achieved by use of H zeolite Y as the catalyst for the bromination of naphthalene with tert-butyl hypobromite (Fig. 8) (ref. 11). It remains to be seen whether further improvements can be achieved by variation of the counterion or by variation of solvent. Such studies are currently in progress. 

A third approach is to apply gas phase bromination. Thus fluorobenzene has been brominated with high p-selectivity over MgY (ref. 22) or with HBr/02 over CuY (ref. 23). 

Metoprolol P,-Selective No 50-1 00 mg twice daily (once daily for extended-release)... 

Wedderbum LR, Robinson N, Patel A, Varsani H, Woo P. Selective recruitment of polarized T cells expressing CCR5 and CXCR3 to the inflamed joints of children with juvenile idiopathic arthritis. Arthritis Rheum 2000 43(4) 765-774. 

Roselius, L., Kurzhals, H. A., Hubert, P., Selective extraction of caffeine from plant materials, Ger. Offen. 2,727,191, 1978. (CA90 85545n)... 

Displacement of [3H]DAMGO (p-selective) and [3H]DSLET (6-selective) from rat brain membrane binding sites. 

The multiple conformational restriction of dermorphin-related tet-rapeptide analogues that was performed represents a rational design of opioid peptidomimetics characterized by a high degree of structural rigid-ification. This is indicated by the fact that the p-selective agonist H-Hat-D-Orn-Aic-Glu-NH2 contains only two freely rotatable bonds, whereas there are 14 freely rotatable bonds in [Leu5]enkephalin. 

Wilkes BC, Schiller PW. Theoretical conformational analysis of a p-selective cyclic opioid peptide analog. Biopolymers 1987 26 1431-1444. 

Weber, A.P. Selecting Propeller Mixers, Chemical Engineering, Sept. 2, 1963, pp. 91-98. 

In toluene disproportionation the highest toluene conversion was achieved over SSZ-33 due to a high acidity combined with 3-D channel system. High toluene conversion over SSZ-35 results from its strong acidity and large reaction volumes in 18-MR cavities. Toluene conversion in the alkylation with isopropyl alcohol is influenced by a high rate of competitive toluene disproportionation over SSZ-33. ZSM-5 exhibits a high p-selectivity for /7-isopropyl toluene, which seems to be connected with diffusion constraints in the channel system of this zeolite. 

Glycosylation of thioglycosides.1 1-Thioglycosides when activated with 1.5 equiv. of C,H,SeOTf, prepared in situ from QH SeCl and AgOTf, react at 0° to -40° with alcohols to form glycosides in 60-95% yield. The reaction is generally p-selective. 

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