Cobinic acid

Cobrynic acid ia which the propionic acid is amidated with l-amino-2-ptopaaol is known as cobinic acid, whereas the compound ia which aU other acids are primary amides is cobiaamide (4). 

Cobinic acid and cobinamide, which aie hnked to libose 3-phosphate, are known as cobamic acid and cobamide (5), respectively. 

The skeleton of vitamin 8,2 (i.e., the porphyrin nucleus minus C-20) is called corrin. The compound containing the corrin nucleus is edled a corrinoid. The compound containing the cobalt atom and the standard side chains in the free acid form is called cobyrinic acid, but cobyric acid when the side chains are at positions a, b, c, d, e, g, are in the amide form. Cobyrinic acid substituted with D-l-amino-2-propanol at position f is called cobinic acid. The substituted cobyric acid is called cobinamide. Cobinic acid substituted with d ribofuranose-3-phosphate at position 2 of the aminopropanol is called cobamic acid the substituted cobinamide is called cobamide. Many 8,2 vitamins and derivatives in which the heterocyclic base is 5,6-dimethylbenzimidazole are given the trivial name cobalamin see D. Dolphin, ed., 8,2, Wiley-Interscience, New York, 1982. 

A series of oc- and j -axial diaquo and aquocyano positional isomer complexes of cobinamide, cobyric acid, and cobinic acids-1, -2 and -3 were separated using a C,g colimm (A = 365nm) and a 30/4/64 acetonitrile/THF/water (80 mM pyridine acetate at pH 3.6) mobile phase [1265]. Retention times varied from 5.4 to 13.6min and resolution times between isomers was always >0.5min. The diaquo-cobinamide and diaquocobinic acid-2 solutes generated tailed peaks. 

The nucleotide-free hexacarboxylic acid in which all amide linkages except the propanolamide link are converted to carboxyl groups is designated cobinic acid (X). The corresponding structure with the primary amide groups intact is referred to as cobinamide (XI). 

The completely amidated cobyrinic acid without isopropanol residues is called cobyric acid. Cobyric acid containing isopropanol is named cobinic acid, and its amide, cobinamide. L-threonine is the precursor for l-amino-2-propanol (Ford and Friedman, 1976). The complete corrinoids contain DMB as the lower (Co-a) nucleotide ligand. In anaerobic producers of corrinoids the synthesis of DMB differs from its aerobic synthesis. Aerobic and aerotolerant microorganisms form this base from FMN. Propionibacteria can use different forms of flavins riboflavin, FMN and FAD as precursors of the vitamin B nucleotide ligand (Jaszewski et al., 1995). 

Etiocobalamin, Cobin-amide dicyanidc vitamin Bl2o Facior B, C H CoN Og mol wt 1042,17. C 57.62%, H 6.96%, Co 5.66%, N 17.47%, O 12 28%. Vitamin factor obtained by removal of the nucleotide from cyanocohal-amin by acid hydrolysis, Isold from calf feces Ford, Porter, Btochem. J- 51, V( 1952) Prepn by acid hydro lysis r Gant et ai,t ibid. 56, XXXIV (1954) Friedrich, Bernhauer, Angew. Chem. 65, 627 (1953). Prepn from factor Vla and D(—)-l amino-2-propanol Bernhauer et al.. Heh. Chim. Acta 43,... 

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