Sulfo derivative, active

Figure 24-8. Biosynthesis of sphingomyelin (A), galactosylceramide and its sulfo derivative (B). (PAPS, "active sulfate," adenosine 3 -phosphate-5 -phospho-sulfate.)...

Figure 3.3 EDC may be used in tandem with sulfo-NHS to create an amine-reactive protein derivative containing active ester groups. The activated protein can couple with amine-containing compounds to form amide bond linkages.

Three main forms of amine-reactive AMCA probes are commonly available. One of them is simply the free acid form of AMCA, which can be used to couple to amine-containing molecules using the carbodiimide reaction (Chapter 3, Section 1.1). The other two are active-ester derivatives of AMCA—the water-insoluble NHS ester and the water-soluble sulfo-NHS ester forms—both of which spontaneously react with amines to create stable amide linkages. All of them react under mild conditions with primary amines in proteins and other molecules to form highly fluorescent derivatives. 

Figure 19.16 A common way of conjugating sulfhydryl-containing haptens to carrier proteins is to activate the carrier with sulfo-SMCC to create an intermediate maleimide derivative. The maleimide groups then can be coupled to thiols to form thioether bonds.

Figure 19.18 Carrier proteins may be activated with sulfo-SMCC to produce maleimide derivatives reactive with sulfhydryl-containing molecules. The graphs show the gel filtration separation on Sephadex G-25 of male-imide-activated BSA (A) and OVA (B) after reaction with sulfo-SMCC. The first peak is the protein and the second peak is excess crosslinker. The maleimide groups create increased absorbance at 280 nm in the activated proteins.

Very little of 7T H7-galactose precursor was converted to a glucocerbroside or to a lactosylceramide under these culture conditions (21). The activities of the sulfotransferase and galactosyltransferase, enzymes responsible for the synthesis of the myelin-associated sulfo- and glycolipids, were also measured at different days in culture (fig. 4). The activities of these enzymes in homogenates of cells derived from the 15 day embryo were relatively low at 8 days but increased until reaching... 

Activated biotin derivatives e.g., Biotin-ONp (EMD Biosciences) or sulfo-NHS-biotin (Pierce). 

Wrasidlo et al. demonstrated the impact of nature and position of different substitutents on the activity with the 2 - and 7-pyridinium and 2 -sulfonate paclitaxel derivatives. They found that the 2 -(A-methyl-pyridinium acetate) paclitaxel (118) behaved more likely as a prodmg, in comparison with 7-pyridinium and 2 -sulfo-nate derivatives, because it showed almost no cytotoxicity and tubulin binding ability in the absence of plasma. However, it exhibited higher in vivo activity and reduced system toxicitiy than those of paclitaxel, whereas 7-pyridinium and 2 -sul-fonate derivatives showed little activities in nude mice although they retained strong cytotoxicities. 

Surprisingly, the symmetric cyclic sulfo-nyl-urea derivative analog (88) (Fig. 15.38, Ki = 3 nM) binds differently in the active site and adopts a flipped conformation (156). 

Quinones and, in particular, naphthoquinone derivatives are industrially valuable products for further processing and for direct use due to their pronounced bioactivity [la,b], 2-Methyl-1,4-naphthoquinone, vitamin K3 ( menadione ), is the basis of the vitamin K group (coagulation vitamins). The skeleton of 2-methyl-1,4-naphthoquinone is common to all fat-soluble K vitamins. Derivatives of vitamin K promote the formation of prothrombin and other blood coagulation factors. They are used on an industrial scale as supplement in animal feed, but are also employed in the treatment of Melaena neonatorum in newborn babies. Trimethyl-p-benzoquinone is a key compound for the synthesis of vitamin E, active as antioxidant agent. As an example, the current method of the production of trimethyl-p-benzoquinone on an industrial scale is p-sulfo-nation of 2,3,6-trimethylphenol followed by stoichiometric oxidation using Mn02 [Ic]. 

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