A new method of analysis of the factor contributing to solvation of small molecules is described. Approximations of the energetic contributions to the entry of a molecule into water have been derived from partition coefficient data of solutes and selected derivatives from a multiplicity of solvents. These include taking separate account energy of the cost of introduction of a molecular cavity i...

Recently, the US Food and Drug Administration proposed a ban on over-the-counter hydroquinone mainly on the basis of high absorption, reports of exogenous ochronosis in humans, and murine hepatic adenomas, renal adenomas, and leukemia with large doses over extended time periods. Systemic exposure to hydroquinone from routine topical application is no greater than that from quantities present in...

Exogenous ochronosis is an infrequent dermatosis characterized as a dark blue hyperpigmentation localized where the causing agent was applied. It may be caused by the use of systemic medication such as antimalarials and by the use of topic substances such as phenol, resorcinol, benzene, or hydroquinone, which is a fenolic compound with depigmentation action, largely used in the treatment of mel...

Allylation and benzylation of p-quinones was achieved through an unusual redox chain reaction. Mechanistic studies suggest that the existence of trace hydroquinone initiates a redox chain reaction that consists of a Lewis acid catalyzed Friedel-Crafts alkylation and a subsequent redox equilibrium that regenerates hydroquinone. The electrophiles could be various allylic and benzylic esters. The ...

AIMS To provide common Organic Chemistry/Polymer Science thermoset free-radical crosslinking Sciences for Medical understanding and also present research findings for several common vitamins/antioxidants with a new class of drugs known as free-radical inhibitors. STUDY DESIGN Peroxide/Fenton transition-metal redox couples that generate free radicals were combined with unsaturated lipid oils t...

The metabolism of quinone-containing antitumor agents involves enzymatic reduction of the quinone by one or two electrons. This reduction results in the formation of the semiquinone or the hydroquinone of the anticancer drug. The consequence of these enzymatic reductions is that the semiquinone yields its extra electron to oxygen with the formation of superoxide radical anion and the original q...