Disulfate

Examples Ca3Mo7024, tricalcium 24-oxoheptamolybdate, may be shortened to tricalcium hep-tamolybdate the anion, MoyOjE, is hep tamo lybdate(6—) S20y , disulfate(2—) P207, diphos-phate(V)(4—). 

Multiplicative Prefixes. The multiplicative prefixes bis, tris, etc., are used with certain anions for indicating stoichiometric proportions when di, tri, etc., have been preempted to designate condensed anions for example, A1K(S04)2 I2H2O, aluminum potassium bis(sulfate) 12-water (recall that disulfate refers to the anion S20jfi. 

Capreomycin disulfate USP is a white solid, soluble ia water and relatively iasoluble ia most organic solvents. It must contain at least 90% capreomycias I. A representative lot contained 25% capreomycin IA, 67% IB, 3% IIA, and 6% IIB (119). The stmctures of capreomycin IA and IB have been determiaed and the compounds synthesized (120). The stmctures of capreomycin IIA and IIB are probably those shown ia Table 4. 

Hydroxylamine can be prepared by a variety of reactions involving the reduction of nitrites, nitric acid or NO, or by the acid hydrolysis of nitroalkanes. In the conventional Raschig synthesis, an aqueous solution of NH4NO2 is reduced with HS04 /S02 at 0° to give the hydroxylamido-A ,A -disulfate anion which is then hydrolysed stepwise to hydroxylammonium sulfate ... 

Pairs of comer-shared SO4 tetrahedra are found in the disulfate.s, (S-O -S 124°,... 

Peroxodisulfuric acid, H2S2O8, is a colourless solid mp 65° (with decomposition). The acid is soluble in water in all proportions and its most important salts, (NH4)2S208 and K2S2O8, are also freely soluble. These salts are, in fact, easier to prepare than the acid and both are made on an industrial scale by anodic oxidation of the corresponding sulfates under carefully controlled conditions (high current density, T < 30°, bright Pt electrodes, protected cathode). The structure of the peroxo-disulfate ion [now preferably called hexaoxo-/r-peroxodisulfate(2-)]0 l is OaSOOSOa " with... 

Like sulfurous acid , disulfurous acid is unknown either in the free state or in solution. However, as indicated in the preceding section, its salts, are readily obtained from concentrated solutions of hydrogen sulfite 2HS03 S2O52- + H2O. Unlike disulfates... 

Imidodisulfates can also be obtained by hydrolysis of nitridotrisulfates (see below). Figure 15.51 compares the structure of the imidodisulfate and parent disulfate ions, as determined from the potassium salts. Comparison with the hydroxyl-amine derivative K[HN(0H)S03] (below) is also instructive. 

Figure 15.51 Comparison of the structures of the imidodisulfate and disulfate ions in their potassium salts.

P0O2 is obtained by direct combination of the elements at 250° or by thermal decomposition of polonium(IV) hydroxide, nitrate, sulfate or selenate. The yellow (low-temperature) fee form has a fluorite lattice it becomes brown when heated and can be sublimed in a stream of O2 at 885°. However, under reduced pressure it decomposes into the elements at almost 500°. There is also a high-temperature, red, tetragonal form. P0O2 is amphoteric, though appreciably more basic than Te02 e.g. it forms the disulfate Po(S04)2 for which no Te analogue is known. 

The filtrate containing the capreomycin is added to 240 liters of methanol with stirring. The methanolic solution of capreomycin is acidified by the addition of one liter of ION sulfuric acid, whereupon the precipitation of the sulfuric acid addition salt of capreomycin commences. The mixture is permitted to stand overnight for more complete precipitation. The supernatant is removed by decanting and filtering. The precipitate, consisting of the capreomycin disulfate, is washed with 10 liters of methanol and is dried in vacuo. Yield 2,510 grams. 

The enol-sulfate form (I), which is the precursor of the luciferin in the bioluminescence system of the sea pansy Renilla (Hori et al., 1972), can be readily converted into coelenterazine by acid hydrolysis. The enol-sulfate (I), dehydrocoeienterazine (D) and the coelenterazine bound by the coelenterazine-binding proteins are important storage forms for preserving unstable coelenterazine in the bodies of luminous organisms. The disulfate form of coelenterazine (not shown in Fig. 5.5) is the luciferin in the firefly squid Watasenia (Section 6.3.1). An enol-ether form of coelenterazine bound with glucopyra-nosiduronic acid has been found in the liver of the myctophid fish Diapbus elucens (Inoue et al., 1987). 

Goto et al. (1974) extracted the arm photophores, and isolated a compound that is highly fluorescent in blue. They determined the structure of this compound to be coelenteramide disulfate (structure A below), and named it Watasenia oxyluciferin. Then, Inoue et al. (1975)... 

The absorption spectra of Watasenia luciferin (coelenterazine disulfate) and Watasenia oxyluciferin (coelenteramide disulfate) are shown in Fig. 6.3.2. Watasenia luciferin in neutral aqueous solutions is auto-oxidized in air more rapidly than coelenterazine, and the compound emits a strong chemiluminescence in the presence of H2O2 ( 10mM) plus Fe2+ ( 0.2mM). Watasenia oxyluciferin is strongly fluorescent in aqueous solutions (Amax 400 nm), 500 times stronger than the fluorescence of coelenteramide in aqueous media (Goto et al., 1974). 

Fig. 6.3.2 Absorption spectra of Watasenia oxyluciferin (A), coelenterazine (B), and coelenterazine disulfate (C), all in methanol. Concentrations 0.1 mM for B and C undetermined for A.

ATP requirement, 202-205 Watasenia luciferin, 201-204, 340 See Coelenterazine disulfate Watasenia prclucifcrin, 160, 163 Watasenia scintillans (Hotaru-ika),... 

C1H03S 7790-94-5) see Actinoquinol Azosemide Bendroflumethiazide Clopamide Diclofenamide Diethylstilbestrol disulfate Dorzolamide Furosemide Glibenclamide Glimepiride Hydroflumethiazide Lomoxicam Mafenide Meticrane Metolazone Saccharin Sildenafil Sodium picosulfate Sulfanilamide Tiotixene Tripamide Xipamide... 

C1SH20O2 56-53-1) see Diethylstilbestrol dipropionate Diethylstilbestrol disulfate Dimestrol Fosfestrol diethyl succinate... 

Another useful reagent for selenenylcyclization is phenylselenenyl triflate. This reagent is capable of cyclizing unsaturated acids101 and alcohols.102 Phenylselenenyl sulfate can be prepared in situ by oxidation of diphenyl diselenide with ammonium peroxy-disulfate.103... 

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