Methylation of chloroplatinate by methylcobalamin

Journal Article · Thu Jan 01 00:00:00 EST 1976 · Bioinorg. Chem.; (United States)

DOI:https://doi.org/10.1016/S0006-3061(00)80014-9· OSTI ID:6896474

Taylor, R T; Hanna, M L

Incubation of ..mu..M levels of K/sub 2/PtCl/sub 6/ and methylcobalamin (MeB-12) results in the complete conversion of MeB-12 to aquoB-12. Demethylation is optimal at pH 2.0 and is accelerated by the addition of K/sub 2/PtCl/sub 4/. The reaction is stoichiometric between MeB-12 and K/sub 2/PtCl/sub 6/ (1 : 1). Incubation of 40 ..mu..M K/sub 2/PtCl/sub 6/ with either 40 ..mu..M (Me-/sup 14/C)MeB-12 or (Me-/sup 3/H)MeB-12 followed by lyophilization converts 70% of the label to a stable form which is associated with Pt upon subsequent paper chromatography and electrophoresis. These is no preferential loss of /sup 3/H relative to /sup 14/C in the reaction product. When 50 ..mu..moles each of (Me-/sup 14/C)MeB-12 and K/sub 2/PtCl/sub 6/ were reacted and subjected to column chromatography, a labeled uv-absorbing product was separated with a /sup 14/C/Pt ratio of 0.9 to 1.2. The /sup 14/C-Pt product has absorption maxima at 260 nm and 208 nm with a minimum at 240 nm (A/sub 240/ nm/A/sub 260/ nm = 0.5). Proton NMR spectroscopy confirmed the presence of an H-C-Pt covalent bonding pattern (J for /sup 1/H, /sup 195/Pt = 78.2 Hz; r for /sup 194/Pt-Me + /sup 196/Pt-Me = 6.956).

• Research Organization: Univ. of California, Livermore
• OSTI ID: 6896474
• Journal Information: Bioinorg. Chem.; (United States), Vol. 6
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
PLATINUM
METHYLATION
VITAMIN B-12
CHEMICAL REACTIONS
CARBON 14
LABELLED COMPOUNDS
PLATINUM CHLORIDES
POTASSIUM COMPOUNDS
TRITIUM
ALKALI METAL COMPOUNDS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CARBON ISOTOPES
CHLORIDES
CHLORINE COMPOUNDS
ELEMENTS
EVEN-EVEN NUCLEI
HALIDES
HALOGEN COMPOUNDS
HYDROGEN ISOTOPES
ISOTOPES
LIGHT NUCLEI
METALS
NUCLEI
ODD-EVEN NUCLEI
PLATINUM COMPOUNDS
PLATINUM METALS
RADIOISOTOPES
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
VITAMIN B GROUP
VITAMINS
YEARS LIVING RADIOISOTOPES
400301* - Organic Chemistry- Chemical & Physicochemical Properties- (-1987)
400201 - Chemical & Physicochemical Properties
400302 - Organic Chemistry- Isotope Effects- (-1987)