D-labeled

Figure A3.5.L The fast ion beam photofragment spectrometer at SRI International. L labels electrostatic lenses, D labels deflectors and A labels apertures.

According to the Foe d Labeling and Education Act (1992), low calorie must contain less than 40 calories per serving and 100 grams of food reduced... 

Environmental assessment or request for categorical exclusion Statements of claimed exclusivity and associated certifications b Prescribing information 0. Annotated labeling text d. Labeling comparison (for ANDA)... 

In most cases, more 1,4- than 1,2-addition product is obtained. This may be a consequence of thermodynamic control of products, as against kinetic. In most cases, under the reaction conditions, 15 is converted to a mixture of 15 and 16, which is richer in 16. That is, either isomer gives the same mixture of both, which contains more 16. It was found that at low temperatures, butadiene and HCl gave only 20-25% 1,4 adduct, while at high temperatures, where attainment of equilibrium is more likely, the mixture contained 75% 1,4 product. 1,2 Addition predominated over 1,4 in the reaction between DCl and 1,3-pentadiene, where the intermediate was the symmetrical (except for the D label) HjCHC—CH—CHCH2D. Ion pairs were invoked to explain this result, since a free ion would be expected to be attacked by Cl equally well at both positions, except for the very small isotope effect. 

Figure 2. The pH dependency of heparin labelling. The degree of labelling intensity of the final product was compared with the concomitantly measured solubility of the F-D labelling reagent.

One of the first practical applications for these fluorescent labelled heparins was to examine the heparin binding behavior of different proteins and peptides under study in our laboratories. To this end we used a modification of the dot-blot assay described by Hirose and colleagues (13). F-D labelled heparin (-1 fluorescein/heparin) was radiolabelled with 125Iodine using iodobeads, to a specific activity of approximately 0.5 x 106 cpm/pg. Solutions of proteins with known heparin-binding capacities were dotted on nitrocellulose paper. A series of replicates... 

Figure 5. Fluorescence anisotropy of F-D labelled heparin-antithrombin interaction. F-D-heparin (0.02 fluoresceins per uronic acid) at 0.1 mg/ml was incubated with different concentrations of antithrombin (open circles) or bovine serum albumin (solid diamonds) in 20 mM sodium phosphate buffer, pH 7.4.

The fluorescent labelling of heparin with F-D by this technique did not observably alter the biologic activity of the heparin as regards to its binding to antithrombin and catalysis of antithrombin s neutralization of activated coagulation factors. F-D labelled heparins also bound to other known heparin-binding proteins in a saturable and reversible manner, as demonstrated by the dot-blot assay technique (Figure 6). 

Figure 6. 125I-F-D Heparin dot blot assay. See text for methods and abbreviations. Upper panel incubation with 125I-F-D labelled porcine mucosal heparin alone, Lower panel the same conditions, but a 100-fold excess of unlabelled heparin has been added to the labelled heparin.

Rothmund M., Schtitz A., Brecht A., Gauglitz G., Berthel G., Graefe D., Label free binding assay with spectroscopic detection for pharmaceutical screening, Fresenius J Anal Chem 1997 359 15-22. 

Figure 5.30 Alternative water pentamer isomers having partial anticooperativity, (a)-(c), or higher coordination and ring strain, (d). Labels in (a)-(c) correspond to clockwise monomer numbering from the top (see the text). (Species (a)-(c) have been optimized under the constraint of planar equilateral skeletal geometry to prevent rearrangement to Wsc [Fig. 5.29(a)] and are therefore only near-stationary points on the potential-energy surface.)...

The crystal structure of an isopropylamine complex of Ru of this type has been reported [78]. Surprisingly, a negligible kinetic isotope effect (kRuHOH/kRUDOD= 1.05 0.14) was found when D labels on both the OH and RuH sites were used,... 

The mechanism of the MPVO reactions has been investigated and questioned on several occasions, and a variety of direct hydrogen-transfer pathways have been suggested (see Scheme 20.4) [31-35]. Recently, racemization of D-labeled 1-phenylethanol with deuterated samarium(III) isopropoxide (17) proved that the MPVO reaction occurs via a direct hydrogen transfer from the a-position of the isopropoxide to the carbonyl carbon of the substrate (Scheme 20.7) [31]. 

Table 8.1 Rate Constants for Forward (Ar+) and Backward (k ) Decompositions of the D-Labeled Formates in Vacuum and Under Ambient D2Q...

In the classical procedures W, the 5-T or D-labeled mevalonate is converted enzymatically to farnesol, which is then oxidized to famesal by liver alcohol dehydrogenase. This enzyme transfers the pro-R hydrogen of C—1 of ethanol or geraniol (or farnesol) to the 4 pro R position of the nicotinamide ring of NAD. 

Tobias et al. [665] have described a method in which the GC effluent is passed into a combustion furnace to convert the organic hydrogen content into water, which is then selectively reduced to hydrogen in a reduction furnace containing Ni metal. The final stream is transmitted to the IRMS via a heated Pd filter, which passes only hydrogen isotopes to the ion source. For a benzene sample a precision of < 5 %o was obtained for <52HSMOw> which approaches the performance of off-line techniques and the requirements for studies of natural variability. This already meets requirements for analysis of D-labeled compounds used in tracer studies [666,667]. 

Human 15-lipoxygenase and soybean LO-1 H/D-atom transfer from per-H vs. per-D Unoleic acid Cll to Fe-O Soybean lipoxygenase-1, WT and L546A mutant, H-atom transfer from H, D labeled linoleic acid Cll to Fe-O... 

Notes i) The isotope effects dealt with in mass spectrometry are usually intramolecular kinetic isotope ejfects, i.e., two competing fragmentations only differing in the isotopic composition of the products exhibit different rate constants k and k, . [69] ii) The kinetic isotope effect is called normal if k k, > 1 and inverse if k ko < 1. iii) Isotope effects can also be observed on KER, [52,70] e.g. the KER accompanying H2 loss from methylene immonium ion varies between 0.61 and 0.80 eV upon D labeling at various positions. [52]... 

Fig. 4 Wild-type zebrafish eleutheroembryo (57 hpf) stained with antibodies specific for slow muscle fibers (F59 a, c) or fast muscle fibers (F310 b, d). Labeling with these antibodies facilitates the analysis of muscle fiber alignments...

Gingras D, Labelle D, Nyalendo C, Boivin D, Demeule M, Barthomeuf C, Beliveau R (2004) Invest New Drugs 22 17... 

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