Complexation of the vitamin B6 with the Cd2+ cation: NMR and X-ray structural study

Pyridoxine

“…1.330 (3)/~ in Cu(PM-H)2.2H20, and 1.307 (4) and 1.314 (4)A in Cu(PM)2(NO3)E.H20; K. J. , and is closer to distances observed in compounds whose phenolic groups are un-ionized [1.343 (6) ,/~ in PN.HC1; Bacon & Plant, 1980]. It is particularly interesting that pyridoxine does coordinate to metals as the zwitterion (Mosset et al, 1978). The transformation to the zwitterion facilitates coordination by the phenolic group, and is reminiscent of the tautomeric change which occurs when pyridoxamine coordinates to metal ions (K. J.…”

“…All of the other structures so far determined of the B 6 vitamins show that the vitamin exists as a zwitterion in which the phenolic group has lost a proton and the pyridine N or amino N (if present) has gained one (Mosset, Nepveu-Juras, Haran & Bonnett, 1978;K. J. Franklin & Richardson, 1980;Longo & Richardson, 1980;Thompson et al, 1980).…”

“…J. Franklin & Richardson, 1980;Hanic, 1966;Longo & Richardson, 1980;Mosset et al, 1978;Thompson et al, 1980). There is a fairly strong intramolecular hydrogen bond from the phenolic OH group to the adjacent CH2OH group (Table 3), which in turn is a hydrogenbond donor to the pyridine N atom in a glide-related molecule.…”

Benzotriazolium hydrogensulphate

“…hydrochloride (Hanic, 1966), but is close to the values observed for vitamin B 6 compounds whose phenolic group is deprotonated (Mosset et al, 1978;K. J. Franklin & Richardson, 1980;Thompson et al, 1980).…”

Metal Complexes as Prospective Antibacterial Agents

“…From early complexation studies, it was evident that thiamine and its derivatives do not readily form true complexes with direct metal-thiamine bonds but instead, they give ionic salts mainly of the type (HT) 2+ (MX 4 ) 2-due to the net positive charge on the thiazolium ring and the easy protonation of pyrimidine N (1) Gramer,1984;Bencini,1987) proved that metal-thiamine complexes exist. Another study on vitamin is the work carried out by Mosset et al(1978). They synthesized Cd(Py)Cl 2 from reaction of aqueous solution (pH=6.5) of equimolar amount of pyridoxine and cadmium chloride.…”