6395-83-1Relevant articles and documents
A new short synthetic approach to chlorocyclopentenones related to cryptosporiopsin via a ring expansion strategy: First synthesis of a fungitoxic metabolite from Sporormia affinis
Kabanyane, Sidima,Decken, Andreas,Yu, Chao-Mei,Strunz, George M.
, p. 270 - 274 (2000)
A metabolite of the coprophilous fungus, Sporormia affinis, 2-trans- allyl-5-chloro-1-hydroxy-4-oxo-2-cyclopentene-1-carboxylic acid methyl ester, 2, was synthesized in racemic form, by an eight-step sequence, in 11% overall yield. Departing from previous ring-contraction strategies for synthesis of chlorocyclopentenones in the cryptosporiopsin series, the key step in the new synthesis was ring expansion of a substituted cyclobutanone, the product of [2+2] cycloaddition of dichloroketene with methyl 2-trimethylsilyloxyhex-2- enoate.
Oxone-mediated oxidative cleavage of β-keto esters and 1,3-diketones to α-keto esters and 1,2-diketones in aqueous medium
Stergiou, Anastasios,Bariotaki, Anna,Kalaitzakis, Dimitris,Smonou, Ioulia
, p. 7268 - 7273 (2013/08/15)
A versatile and highly efficient method for the direct synthesis of α-keto esters and 1,2-diketones has been developed. This approach utilizes the oxidative cleavage of a variety of β-keto esters and 1,3-diketones mediated by an Oxone/aluminum trichloride system. The simple one-step oxidation reaction proceeded selectively in aqueous media to afford products in high yields, short reaction times, and environmentally benign conditions.
Amines that transport protons across bilayer membranes: Synthesis, lysosomal neutralization, and two-phase pKa values by NMR
Dubowchik, Gene M.,Padilla, Linda,Edinger, Kurt,Firestone, Raymond A.
, p. 4676 - 4684 (2007/10/03)
It is desirable to be able to control the pH of lysosomes. A collection of lipophilic, nitrogenous bases, designed to act as membrane-active, catalytic proton transfer agents, were prepared and their effective pKas measured in a vigorously stirred, two-phase system. One phase was a phosphate buffer whose pH was varied over the range ca. 1-11. The other was an immiscible, deuterated organic solvent in which the compounds preferentially resided even when protonated. When chemical shift changes versus the pH of the buffer were plotted, clear pKa curves were generated that are relevant to transmembrane proton transfer behavior. The two-phase pKas increased with increasing counterion lipophilicity and with increasing organic solvent polarity. The compounds were also tested for their ability to neutralize the acidity of lysosomes, a model for other acidic vesicles involved in drug sorting. The most successful of these, imidazole 6a, has > 100 times the neutralizing power of ammonia, a standard lysosomotropic amine, causing a 1.7 unit rise in lysosomal pH of RAW cells at 0.1 mM, compared to a 0.2 and 1.4 unit rise for ammonium chloride at 0.1 and 10 mM, respectively.
