Metal-sugar complexes

Amino peptidases zinc, 6,606 Amino sugars metal complexes geochemistry, 6, 867 Ammonia... 

Ab initio SCF energy calculations were used to determine the structures of several carbohydrates [46-47]. The PCILO method [48] was applied to carbohydrates [49]. The X-a method [50] can be parametrized for metal atoms so that calculations on sugar-metal complexes are possible (for example, the studies on sugar-metal interactions by Tajmir-Riahi [51]). 

Such sugar-metal complexes as (444) were formed in high yield by electrolysis of the appropriate ligand (see p. 133) in methanolic solution using anodes of the metal (Cu or Ni or Co) and a platinum cathode. The interaction between Cu cations and adenosine, guanosine, cytidine, and uridine in aqueous DMSO at various pH values has been studied by e.s.r. and n.m.r. spectroscopy. Since Cu cations were shown to complex specifically with 0-2 and 0-3 of these nucleosides at pH 8.5-10, complex formation can be used to distinguish 5 -ribonucleotides from 2 - and 3 -ribonucleotides and 2 -deoxyribonucleosides. Under certain conditions, Cu cations can form complexes having as many as four bases bound to the metal. 

Burger, K. Nagy, L. Metal complexes of carbohydrates and sugar-type ligands. In Burger, K. (Ed.), Biocoordination Chemistry, Chichester, Ellis Horwood, 1990 Chapter VI, p. 236. 

Henderson, S. K. and Henderson, D. E., Enhanced UV detection on sugar phosphates by addition of a metal complex to the HPLC mobile phase,... 

For systemic administration, the photosensitizer usually has to be delivered into the bloodstream by intravenous injection. Since the photosensitizer is a solid, this means that a solution or a stable suspension has to be provided. Metal complexes of the basic porphyrin and phthalocyanine nuclei are insoluble in water, so that some effort has to be made to render the system water soluble, or at least amphiphilic, by placing various substituents (e.g., S03H, C02H, OH, NR3+, polyether, aminoacid, sugar) on the periphery of the molecule. The aromatic character of the ligand offers a suitable opportunity for such substitutions to be made. Examples will appear frequently in the following sections. 

S. Orlandi, R. Annunziata, M. Benaglia, F. Cozzi, and L. Manzoni, Synthesis of some oligopyridine-galactose conjugates and their metal complexes A simple entry to multivalent sugar ligands, Tetrahedron, 61 (2005) 10048-10060. 

Kirsch-De-Mesmaeker A, Lecomte J-P, Kelly JM (1996) Photoreactions of Metal Complexes with DNA, Especially Those Involving a Primary Photo-Electron Transfer. 177 25-76 Kirschning A, Bechthold A F-W, Rohr J (1997) Chemical and Biochemical Aspects of Deoxy-sugars and Deoxysugar Oligosaccharides. 188 1 - 84 Kitazume T.Yamazaki T (1997) Enzymatically Controlled Reactions of Organofluorine Compounds. 193 91 -130... 

The interaction of oxygen-containing acyclic ligands with alkali and alkaline earth metal cations has provided a burgeoning area of interest. In historic terms, this was preceded by the advent of crown ethers and the accompanying almost retrospective look at their acyclic precedents. This section is sub-divided into five parts simple chelates, metal complexes as ligands, podands, polypodands and sugars. 

The literature on metal complexes of carbohydrates through 1965 has been fully reviewed by Rendleman (I), and we shall therefore only discuss recent work. We shall not discuss the complexes formed with strong bases, such as calcium and barium oxide these are salts in which the sugar acts as a weak acid, losing one or several protons. Nor shall we discuss the complexes formed with anions of oxyacids—e.g., borate, stannate, periodate, etc. ions all these are compounds formed by covalent bonds in alkaline solution. We are concerned only with complexes formed with cations in neutral aqueous solution there is no evidence for the formation of complexes between sugars and simple anions in neutral aqueous solution. (For an example of complex formation between a sugar derivative and chloride ion in chloroform solution, see Reference 3.)... 

The metal complexes of sugars have many potential uses. Sometimes sugars which have not yet been obtained in the crystalline form can be... 

The food fiavorist also must be aware of metal complexes, which carbohydrates are capable of forming, Iron salts not only form complexes with dietary fiber, but with nearly all of the known natural sugars. Fructose, maltitol. sorbitol, and xylitol can easily form complexes with the ferric... 

---