Quinone derivatives of the general formula: ##STR1## (wherein R.sup.1 and R.sup.2 are the same or different, and independently are a hydrogen atom or a methyl or methoxy group, or R.sup.1 and R.sup.2 combine with each other to represent --CH.dbd.CH--CH.dbd.CH--R.sup.3 is a hydrogen atom or a methyl group; R.sup.4 is an aliphatic, aromatic or heterocyclic group which may be substituted; R.sup.5 is a methyl or methoxy group, a hydroxymethyl group which may be substituted or a carboxyl group which may be esterified or amidated; Z is a group represented by --C.dbd.C--, --CH.dbd.CH--, ##STR2## n is an integer of 0 to 10; m is an integer of 0 to 3; k is an integer of 0 to 5, provided, however, that in the case of m being 2 or 3, Z and k can vary arbitrarily within the bracketed repeating units) are novel compounds, possess metabolism ameliorating action for polyunsaturated fatty acids, particularly production inhibitory activity of lipid peroxides (antioxidant activity), thromboxane A.sub.2 receptor antagonism, or production inhibitory activity of 5-lipoxygenase metabolites in mammals, and of use as drugs, such as antiasthmatic, antiallergic agent and cerebral-circulatory metabolism ameliorating agent.
Et<sub>2</sub>Zn-Mediated Rearrangement of Bromohydrins
作者:Lezhen Li、Peijie Cai、Qingxiang Guo、Song Xue
DOI:10.1021/jo800231s
日期:2008.5.1
and highly efficient method for the rearrangement of bromohydrins mediated by Et2Zn to synthesize carbonylcompounds was described. Various β-bromo alcohols were treated with 0.6 equiv of Et2Zn to form a zinc complex in CH2Cl2 at room temperature for 2 h, followed by 1,2-migration to give the corresponding carbonylcompounds. This remarkable and clean rearrangement is general for acyclic and cyclic bromohydrins
Ring Enlargements VI. The Diazomethane-Carbonyl Reaction: Product Ratios from the Reactions of Diazomethane with Various Substituted 2-Phenylcyclohexanons<sup>1</sup>
作者:C. DAVID GUTSCHE、HERBERT F. STROHMAYER、JOSEPH M. CHANG