The catalytic, enantioselective, [4 + 2] cycloaddition reaction of ortho-quinone methides with silyl ketene acetals is described. This mechanistically interesting reaction, initiated by a chiral cinchona alkaloid-derived ammonium fluoride "precatalyst" complex, affords a variety of alkyl- and aryl-substituted 3,4-dihydrocoumarin products in excellent yield and with good enantioselectivity.

Alpha Hope is a dietary supplement containing pyrroloquinoline quinone and elemental magnesium, which produces molecular hydrogen (H2 gas) when dissolved in water. We determined the impact of on Nrf-2, peroxisome proliferator-activated receptor-gamma coactivator (PGC-1α), citrate synthase (CS) activity C2C12 myoblasts. was titrated to three concentrations (PQQ) (10 nM, 100 1000 nM) treated for ...

The Entner-Doudoroff pathway was shown to be induced for oxidative glucose metabolism when Escherichia coli was provided with the periplasmic glucose dehydrogenase cofactor pyrroloquinoline quinone (PQQ). Induction of the Entner-Doudoroff pathway by glucose plus PQQ was established both genetically and biochemically and was shown to occur in glucose transport mutants, as well as in wild-type E....

The GOX1857 gene, which encodes a putative membrane-bound pyrroloquinoline quinone (PQQ)-dependent dehydrogenase in Gluconobacter oxydans ATCC 621H, was characterized. GOX1857 was disrupted and the oxidizing potential of the resulting mutant strain was compared to that of the wild-type. In contrast to the wild-type, the mutant was unable to grow with myo-inositol as the sole energy source and d...