Some Derivatives of Gallic Acid and Pyrogallol

Abstract

The facts that the halogen becomes affected in this manner only when it is in Rings B or C, and therein only when in Position 3, are interpreted as indicating that of the four rings in the acridyls only these two are capable of undergoing a tautomeric change from benzenoid (VII) to the more reactive quinonoid state (VIII). The conclusion is drawn that in the acridyls, in common with other free radicals, the acquisition of the property of selective absorption on the one hand, and on the other, their capacity to exist tautomerically in the quinonoid state, are concomitant phenomena.

Cis−Trans Isomerization of a Cyclopropyl Radical Trap Catalyzed by Extradiol Catechol Dioxygenases: Evidence for a Semiquinone Intermediate

“…Chemicals. 2,3-Dihydroxyphenoxyacetic acid was synthesized from pyrogallol according to the method of Christiansen …”

Isopropyl 3,4,5-trihydroxybenzoate

“…For the synthesis method, see: Christiansen (1926); Li et al (2001). For the hydrogen-bonding pattern, see: Bernstein et al (1995).…”

Isolation and characterization of Escherichia coli mutants defective for phenylpropionate degradation

“…When used as sources of carbon for growth, aromatic acids were supplied at 0.5 mg/ml and glycerol at 1 mg/ml. Nutritional supplements were supplied at the following concentrations: Lamino acids, 40 ,ug/ml; nucleotide bases, 20 ,ug/ml; and vitamins and cofactors, 5 tional freeze-thaw cycles, particulates were removed by centrifugation at 27,000 x g for 20 min, and the supernatant was used as a cell extract for enzyme assays. Protein was determined by the method of Lowry et al (34) or by measuring the absorbance at 230 and 260 nm as described by Kalb and Bernlohr (31).…”