Latent/active

Over the past years it has become apparent that the cell type is an important determinant of the extent of oxidative stress that may occur. Both the latent activities of cytoprotective enzymes in specific cell types, as well as the ability of the cell to respond rapidly to an oxidative insult by the upregulation of such enzymes, will be important predeterminants of the fate of the cell. Table 10.1 shows the concentrations of both antioxidants and cytoprotective enzymes in a variety of tissues. While the liver is well provided with antioxidant protection, the brain has very low levels, so the ability to respond rapidly to an oxidative insult by upregulation of gene transcription and translation will be an important determinant of survival or death. Cells such as hepatocytes have high levels of expression and... 

A novel latent-active glycosylation strategy was reported. This strategy is based on a rhodium-catalyzed isomerization of substituted allyl glycosides followed by a Lewis acid-mediated glycosylation reaction (Scheme 46).76 77... 

The amount of total enzymatic activity that becomes manifest only after disruption of membranous barriers between enzyme and substrate or upon removal of some otherwise inhibitory factor. Membrane disruption is often achieved by treatment with detergent to solubihze the enzyme. One example is the so-called microsomal glucose-6-phosphatase, an enzymatic activity that is located in the lumen of the endoplasmic reticulum but becomes trapped as a latent activity in microsome vesicles upon mechanical disruption of cells. 

SPECIFIC ACTIVITY TURNOVER NUMBER OPTICAL ACTIVITY ACTIVITY COEFFICIENT CHEMICAL POTENTIAL FUGACITY LATENT ACTIVITY BIOMINERALIZATION ACTIVITY COEFFICIENT ACTIVITY... 

LANGMUIR TROUGH AND BALANCE LAPLACE TRANSFORM LARMOR PRECESSION LASER-FLASH KINETIC ANALYSIS LATENT ACTIVITY LATENT HEAT Latent heat of fusion LATENT HEAT Latent heat of vaporization LATENT HEAT Lateral binding proteins,... 

Connors TA. 1978. Antitumour drugs with latent activity. Biochimie 60 979-987. 

The techniques of Hindsgaul s random glyco-sylation. Boons s latent-active glycosylation and Kahne s solid phase methodology now make the synthesis of di- and trisaccharide combinatorial libraries a feasible process. Also, a colorimetric... 

Boons G-J, Isles S. Vinyl glycosides in oligosaccharide synthesis (part 1) a new latent-active glycosylation strategy. Tetrahedron Lett. 1994 35 3593-3596. 

The free acid phosphatase activities expressed as percentage of the total acid phosphatase activity for each of the fractions were nuclear, 53 mitochondrial, 33 light mitochondrial, 55 microsomal, 127 supernatant, 101. The sum of the free activities of all fractions was 71% of the total activity. The comparable values for the fractionation of rat liver (DIO) were nuclear, 60 mitochondrial, 18 light mitochondrial, 12 microsomal, 50 supernatant, 106. The sum of the free activities of all fractions was 22% of the total activity. Thus the latent activity of acid phosphatase in the prostate was less than in the liver. 

SCHEME 4.31 Vinyl glycosides in latent-active glycosylation. 

A new type of latent-active glycosyl donors, 2 -carboxybenxyl glycosides and their benzyl esters, have been recently introduced [62-64]. The active carboxylic acids are readily available from the latent benzyl esters by catalytic hydrogenation in the presence of ammonium acetate. In an example [62] shown in Scheme 5.24 the latent mannoside (136) was glycosylated with the active donor (135) to provide exclusively the p-linked disaccharide (137) in excellent yield. The latent... 

Boons, G J, Heskamp, B, Hout, F, Vinyl glycosides in ohgosaccharide synthesis a strategy for the preparation of trisaccharide hbraries based on latent-active glycosylations, Angew. Chem. Int. Ed. Engl, 35, 2845-2847, 1996. 

Vinyl glycoside-based latent-active strategy for glycosyl coupling... 

O Scheme 71. All glycosyl couplings were based on the latent-active methodology, and all were stereoselective. A slightly modified synthesis of 439 has been reported including one CB mediated coupling [216]. 

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