Urate salts

Uric acid is the endproduct of purine metabolism in man. Uric acid has a lower solubility than its progenitor metabolites, hypoxanthine and xanthine. Impaired uric acid elimination and/or increased uric acid production result in hyperuricemia and increase the risk of gouty arthritis. At physiological pH, 99% of the uric acid molecules are actually in the form of the urate salt. A decrease in pH increases the fraction of uric acid molecules relative to urate molecules. Uric acid possesses lower solubility than urate. 

Humans catabolize purines to uric acid (pA 5.8), present as the relatively insoluble acid at acidic pH or as its more soluble sodium urate salt at a pH near neutrality. Urate crystals are diagnostic of gout. Other disorders of purine catabolism include Lesch-Nyhan syndrome, von Gierke s disease, and hypo-uricemias. 

Lithium, like alcohol, can influence mood. This was discovered nearly 50 years ago by Cade (468), who was investigating the effects of lithium urate merely because it is a soluble urate salt. Lithium and not urate turned out to be the effective agent. Simple salts such as Li2C03 are widely used (by as many as 1 in every 1000 of the popula-... 

Pyrimidines and purines derivatives act as bases and can be acquired through the diet. In particular, organ meats such as liver are a rich source of DNA and RNA. Most dietary purines are oxidized by enzymes to uric acid in the intestinal mucosa that is their excretory product in humans. The desease known as gout is related to high levels of uric acid in serum and the result of deposition of urate salts in various tissues. 

Uric acid is one of the principal end products of purine metabolism. Gout is caused by elevated levels of uric acid in the body, causing crystals of urate salts to precipitate in the joints. 

Uric acid and its urate salts are very insoluble and can present difficulties in mammalian metabolism. Hyperuricemia is a condition characterized by chronic elevation of blood uric acid levels beyond normal levels. Also known as gout, it affects 3 people in 1000. High levels of urate leads to precipitation of sodium urate in the synovial fluid of joints. Precipitates can cause inflammation, arthritis, and/or severe degeneration of the joints. 

In its role in purine catabolism, XnDH catalyzes sequential hydroxylation of the C-2 and C-8 atoms of hypoxanthine, converting it first to xanthine and then to uric acid (eqn (7.1), keto forms shown). In humans, enzyme deficiency is associated with xanthinuria types I and II, the symptoms of which include urinary tract infections, myopathy, arthritis, arthralgia, kidney stones and acute renal failure, while over-activity causes hyperuricemia and the deposition of urate salts in the joints leading to gout. ... 

It was quite recently reported that La can be electrodeposited from chloroaluminate ionic liquids [25]. Whereas only AlLa alloys can be obtained from the pure liquid, the addition of excess LiCl and small quantities of thionyl chloride (SOCI2) to a LaCl3-sat-urated melt allows the deposition of elemental La, but the electrodissolution seems to be somewhat Idnetically hindered. This result could perhaps be interesting for coating purposes, as elemental La can normally only be deposited in high-temperature molten salts, which require much more difficult experimental or technical conditions. Furthermore, La and Ce electrodeposition would be important, as their oxides have interesting catalytic activity as, for instance, oxidation catalysts. A controlled deposition of thin metal layers followed by selective oxidation could perhaps produce cat-alytically active thin layers interesting for fuel cells or waste gas treatment. 

Two procedures have been developed for the aminohydroxylation of a, 3-unsat-urated amides Procedure A for products that are insoluble in the reaction mixture and Procedure B for soluble products (Scheme 12.17) [48]. These differ only in that the former requires a 10-25% excess of chloramine-T and t-BuOH as the cosolvent, while the latter uses only one equivalent of the chloramine salt and MeCN as the cosolvent. The excess of chloramine-T in Procedure A allows better turnover near the end of the reaction, and the trace amount of p-toluenesulfonamide byproduct can be removed by recrystallization. However, elimination of the necessity to remove p-toluenesulfonamide far outweighed the inconvenience of slightly longer reaction times needed in procedure B without the use of excess chloramine salt. 

The removal and reduction of the nucleic acid content of various SCPs is achieved by chemical treatment with sodium hydroxide solution or high salt solution (10%). As a result, crystals of sodium urate form and are removed from the SCP solution.16,17 The quality of SCP can be upgraded by the destruction of cell walls. That may enhance the digestibility of SCP. With chemical treatment the nucleic acid content of SCP is reduced. 

Analysis of Guano.—Guano is a very complex mixture, containing urate, oxalate, and phosphate of ammonia, earthy phosphates, soluble alkaline salts, and organic matter, The analysis of such a compound is attended with some labor. As the value of guanos, however, depends on the quantify of ammonia, phosphates, soluble and insoluble, and alkaline 6alts which they contain, a very simple analysis is quite sufficient for agricultural purposes.. 

Uric acid CAS 69-93-2, (C5H4O3N4) is a white solid, insoluble in cold water, alcohol or ether, sparingly soluble in hot water. Uric acid is a weak dibasic acid thus forming two series of salts, most of which are very slightly soluble in water (lithium urate soluble),... 

Grains anhydrous salt per 100 grams water in a sat urated solution at 0 25° 100 ... 

The reaction of trans-dimethoxy tellurium tetrafluoride with pyridine produced pyridinium /ra .v-(methoxy)oxo(tetrafluoro)tell urate (VI). The tetramethylammonium salt was obtained, when trans-dimethoxy tellurium tetrafluoride was reacted with trimethylamine in dichloromethane2. Treatment of these salts with 96% sulfuric acid gave trans-hydroxy methoxy tellurium tetrafluoride. ... 

Dr. J. F. J. Cade, an Australian psychiatrist, first reported on the beneficial use of a lithium compound for a psychiatric disorder, namely, manic behavior in 1949. The early human trials were undertaken after initial experiments on rats, which became quite lethargic after treatment with lithium urate. Fairly large doses were required for treating manic behavior and its use for this disorder has been displaced by organic drugs that carry less risk. His report, however, led to its current nse as a treatment for bipolar affective disorder (also known as manic-depressive disorder). Its use in the United States was curtailed for a decade and a half by the US. Food and Dmg Administration (FDA), which based its decision on incidental poisonings due to overuse of a lithium-based table salt substitute, despite a safe record of controlled psychiatric apphcations in Europe. It has been estimated that by 1985... 

SYNS MONOSODIUM URATE IH-PURINE-2,6,8(3H)-TRIONE, 7,9-DIHYDRO-, MONOSODIUM SALT (9CI) URIC ACID, MONOSODIUM SALT... 

Uric acid in very low concentrations, very strongly absorbs UV radiation and for this reason, has been used to protect various FD C colors against fading when they will be probably exposed to direct sunlight (112). Uric acid has been found to enhance the photostability of solutions of colchicine (70) and FD C Blue No. 2 (82,113). Sodium urate, the neutral salt of uric acid, has a photoprotective effect on solutions of metronidazole (68), doxorubicin hydrochloride (77), and physostigmine sulfate (108). In addition to its photon-absorbing property, uric acid has been reported to also possess antioxidant quality (114). 

Moderate renal failure is defined as the situation where the GFR is 30-70 rnl/min, while severe renal failure is where the GFR is under 30 ml/min. In chroitic renal failure, the gradual destruction of nephrons is compensated by hypertrophy of the remaining nephrons. Hence, the kidney continues to excrete normal levels of salt and water even with a moderate reduction in the GFR (Martin, 1996). Eventually, however, tirea and other nitrogenous compounds (am-monia, guaitidine, urate) begin to accumulate in the bloodstream. The increase in some of these compounds produces the nausea, vomiting, and tiredness that makes the patient first aware of the renal failure. Uremia occurs when the CER fails below 20-25% the normal value (Brenner and Lazarus, 1994). 

Precipitant A chemical used to promote protein crystallization, but not denat-uration. Examples are highly soluble inorganic salts (ammonium sulfate or sodium chloride), and organic polyethers (polyethyleneglycols of a selected molecular weight range). 

Gout is an inflammatory condition that attacks joints, tendons, and other tissues. The most common site is at the joint of the big toe. Gout is caused by problems metabolizing uric acid and purine, which is produced by proteins. The inability to metabolize uric acid and purine results in a buildup of urates (uric acid salts) and uric acid called hyperuricemia. Uric acid is also not cleared by the kidneys. Urate crystals form urate calculi known as stones that appear as tophi (bumps) in the subcutaneous tissue of earlobes, elbows, hands, and the base of the large toe. 

Stable but as with the imidazolide it may be protected as the TBS ether to improve its stability. The pyrrole carbinol is sufficiently stable as the lithium salt that aryl halides may be metalated with BuLi. These derivatives may also be converted directly to a,P-unsat-urated esters using the Wadsworth-Horner-Emmons olefination using the Masamune-Roush protocol. Deprotection is accomplished with catalytic DBU or NaOMe. ... 

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