Riboflavin 5 -Phosphate Ester

Flavin Mononucleotide, Sodium Salt Riboflavin 5 -Phosphate Ester Monosodium Salt Riboflavin 5 -Phosphate Ester Monosodium Salt, Dihydrate... 

Riboflavin 5 -phosphate ester monosodium salt. See Riboflavin-5 -phosphate sodium Riboflavin-5 -phosphate sodium CAS 130-40-5 (dihydrate) EINECS/ELINCS 204-988-6... 

Synonyms Riboflavin monophosphate monosodium salt Riboflavin 5 -monophosphate sodium salt dihydrate Riboflavin 5 -phosphate ester monosodium salt Riboflavin 5 - (sodium hydrogen phosphate) Riboflavin sodium phosphate Sodium riboflavin phosphate (INCI) Vitamin B2 phosphate sodium... 

Riboflavin is the redox component of flavin adenine dinucleotide FAD. It is derived from FAD by hydrolysis of a phosphate ester link. The fully oxidised form of FAD is involved in many dehydrogenaze reactions during which it is converted to the fully reduced form. The fully oxidised state is restored either by another redox enzyme or by interaction with oxygen and hydrogen peroxide is liberated. The one-electron reduced, semiquinone form of FAD, is involved in some electron transfer steps. 

Riboflavin-5 -phosphate sodium (IFN 7-17-901), the sodium salt of the phosphate ester of riboflavin. 

The vitamin is commercially available as riboflavin, riboflavin S-phosphate. and riboflavin S-phosphate sodium. The phosphate esters are used commercially only in multivitamin preparations, and they are hydrolyzed before absorption occurs. Ab.sorption occurs through an active transport. system in which riboflavin is phosphorylated by the intestinal mucosa during absorption. Food and bile enhance absorption. Riboflavin is distributed widely in the body, with limited stores in the liver, spleen, heart, and kidneys. Conversion to FAD occurs primarily in the liver. FMN and FAD circulate primarily protein bound. Only small amounts ( 9%) are excreted in the urine unchanged. Larger amounts can be found after administration of large doses. 

Several vitamins are naturally fluorescent, a physical characteristic that can be used in their sensitive and selective detection in LC. The detection limit for riboflavin by fluorescence detection is less than 1 pmol, whereas in UV detection it is 30 times higher. The detection of an LC assay for thiamin and its phosphate esters using the fluorimetric... 

Bis(3-pyridinecarbonyl), 4 (5 )-phos-phate Riboflavine 2, 3 dU3-pyridinecar boxylate monodihydrogen phosphate (ester), 9CI. FMN-dinicotinate [36119-03-6]... 

Riboflavine 4, 5 -cyclic phosphate, R-95 Riboflavine 5 -(dihydrogen phosphate), 9CI, R-95 Riboflavine 2, 3 -di-3-pyridinecarboxylate monodihydrogen phosphate (ester), 9C1, R-95... 

Riboflavin readily decomposes through the action of light and of alkalies. It is sparingly soluble in water but can be extracted by adding pyridine or acetic acid or by using dilute mineral acids. It is stable in acid solution. Vitamin Bg occurs in nature as phosphate ester and, further, as adenine dinucleotide or linked to protein it must be liberated by enzymatic treatment before determination. 

Interestingly, the synthesis of riboflavin phosphate has taken a shghtly different course. As reported in 1950 (Scheme 12.116), when the reduced Al-ribosyl derivative of 2,3-dimethylaniline is phosphorylated with phosphorus oxychloride and then carefully hydrolyzed, the corresponding monophosphate is capable of isolation. Then, treatment of that ester with diazotized aniline yielded l-D-l -ribitylamino-6-phenylazo-3,4-dimethylbenzene. Reduction to the corresponding amine followed by condensation with alloxan then yielded riboflavin monophosphate. 

Yagi and Okuda (131) have reported the formation of riboflavin 5 -phos-phate from riboflavin by transphosphatation with several phosphate esters (jS-glycerophosphate, phenyl phosphate, adenosine monophosphate) in the presence of intestinal alkaline monophosphatase. 

They have suggested that this phosphorylation mechanism, in addition to flavokinase, may be of physiological importance in the formation of riboflavin 5 -phosphate. It remains to be seen whether conditions (e.g., concentration of an appropriate phosphate ester, optimum pH for enzyme... 

The alcoholysis of the cyclic phosphate of catechol by alditols can lead, after acid hydrolysis of intermediate, cyclic phosphates, to the selective formation of phosphoric esters of the primary hydroxyl groups in the alditols. Thus, erythritol and D-mannitol afford, after chromatographic purification of the reaction products, their 1-phosphates in yields of 31 and 38%, respectively.217 The method was used to convert riboflavine into riboflavine 5 -phosphate.218 1-Deoxy-1-fluoro-L-glycerol has been converted into the 3-(dibenzyl phosphate) in 54% yield by selective reaction with dibenzyl phosphorochloridate. 219... 

Bi) is converted to thiamine pyrophosphate simply by the addition of pyrophosphate. It is involved in aldehyde group transfer. Niacin (nicotinic acid) is esterified to adenine dinucleotide and its two phosphates to form nicotinamide adenine dinucleotide. Pyridoxine (vitamin B ) is converted to either pyridoxal phosphate or pyridoxamine phosphate before complexing with enzymes. Riboflavin becomes flavin mononucleotide by obtaining one phosphate (riboflavin 5 -phosphate). If it complexes with adenine dinucleotide via a pyrophosphate ester linkage, it becomes flavin adenine dinucleotide. 

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