“Blackening” Porphyrins by Conjugation with Quinones

Crane-quinones with Coenzyme

4. CRANE, F. L., LESTER, R. L., WIDMER, C. and HATEFI, Y. Studies on the electron transport system XVIII. Isolation of coenzyme Q from beef heart and beef heart mitochondria. Biochim. Biophys. Acta 32: 73-79. 1959. 5. CRANE, F. L., WIDMER, C., LESTER, R. L. and HATEFI, Y. Studies on the electron transport system XV. Coenzyme Q (Q275) and the succinoxidase activity of the electron transport part...

Glutathione transferase M2-2 catalyzes conjugation of dopamine and dopa o-quinones.

Human glutathione transferase M2-2 prevents the formation of neurotoxic aminochrome and dopachrome by catalyzing the conjugation of dopamine and dopa o-quinone with glutathione. NMR analysis of dopamine and dopa o-quinone-glutathione conjugates revealed that the addition of glutathione was at C-5 to form 5-S-glutathionyl-dopamine and 5-S-glutathionyl-dopa, respectively. Both conjugates were fou...

Influence of Nitrogen Bases on Epoxidation of Cyclooctene with Sodium Periodate Catalysed by Manganese(III) Porphyrins

Effects of imidazoles and substituted pyridines and pure s-donors on the oxidation of cyclooctene with NaIO4 by 5,10,15,20-tetraphenylporphyrinato-manganese(III) acetate, Mn(TPP)OAc, and 5,10,15,20-Tetramesitylporphyrinato-manganese(III) acetate, Mn(TMP)OAc, catalysts in CH2Cl2-H2O solvent are studied. Coordination of the nitrogen donors to the Mn...

Reaction of Quinones with Nitrosoarenes

Formation of the 2,3-dicyanohydroquinone (3) can be rationalised in terms of preferential addition of cyanide at the most electron deficient unsubstituted carbon of the cyanoquinone (2 ) in the same way as alcohols and other nucleophiles add to the 3-position of the acylquinone ( 8 ) [4], However, such an argu­ ment could not be applied to the formation of the dihydroxylamine (6 ). Hence, eithe...

Conjugation of spermine facilitates cellular uptake and enhances antitumor and antibiotic properties of highly lipophilic porphyrins.