SmCl3 (20 mol%) has been used as an efficient catalyst for reaction between aromatic aldehydes and 5,5-dimethyl-1,3-cyclohexanedione at 120°C to give 1,8-dioxo-octahydroxanthene derivatives in high yield. The same reaction in water, at room temperature gave only the open chain analogue of 1,8-dioxo-octahydroxanthene. Use of eco-friendly green Lewis acid, readily available catalyst and easy isol...

We report results from experiments with a pseudo-one-dimensional Belousov-Zhabotinsky reaction that employs 1,4-cyclohexanedione as its organic substrate. This excitable system shows traveling oxidation pulses and pulse trains that can undergo complex sequences of propagation failures. Moreover, we present examples for i breathing pulses that undergo periodic changes in speed and size and ii ba...

Five classes of herbicides (carbamothioates, chloroacetamides, substituted pyridazinones, cyclohexanediones, and aryloxyphenoxypropionic acids) have been reported to inhibit lipid biosynthesis in higher plants. Carbamothioates impair the synthesis of surface lipids (waxes, cutin, suberin). These effects have been attributed to the ability of this herbicide class to inhibit one or more acyl-CoA ...

Aminoacetylation of lysine residues and the modification of arginine by 1,2-cyclohexanedione to N7,N8-(dihydroxy-1,2-cyclohexylidene)arginine were used for probing the surface topology of hen-eggwhite lysozyme as a model protein. The molecular identification of lysine and arginine modification sites was provided by molecular weight determinations of modified and unmodified tryptic peptide mixtu...

The conversion of very low density (VLDL) to low density lipoproteins (LDL) is a two-step process. The first step is mediated by lipoprotein lipase, but the mechanism responsible for the second is obscure. In this study we examined the possible involvement of receptors at this stage. Apolipoprotein B (apoB)-containing lipoproteins were separated into three fractions, VLDL (Sf 100-400), an inter...

The reaction of formaldehyde with β-diketones (Hantzsch reaction) has been often employed for derivatizing formaldehyde to the fluorescent compounds.1,2 Among βdiketones, 5,5-dimethyl-1,3-cyclohexanedione (dimedone, Fig. 1) seems to be the most promising because of the strong fluorescence intensity and stability of the formed compound. Recently, we developed a method for concentrating trace hyd...

A fast one-pot method has been developed for the direct preparation of 3-aryl-1,2-cyclohexanediones from 2,3-epoxycyclohexanone via a microwave-assisted tandem epoxy ketone isomerization-Heck arylation reaction. The preparative microwave-assisted reactions were performed preferentially in 50% aqueous poly(ethylene glycol) utilizing sodium acetate as the base. Within 5-30 min of directed microwa...

The organocatalytic enantioselective desymmetrization reaction by means of an intramolecular (hetero)Michael addition is a useful strategy for the creation complex carbo- and heterocycles with generation multiple stereocenters in very simple manner. carbon, oxygen nitrogen nucleophiles to prochiral substrates bearing electronically deficient olefins takes place presence organocatalysts, such as...

We describe an experimental methodology for the study of chemical self-organization in micropatterned reaction systems. Our approach is based on office-printer-assisted soft lithography and allows the fabrication of centimeter-scale devices with reactor units as small as 50 μm. The devices are made from the elastomeric material poly(dimethylsiloxane) and are filled with a modified Belousov-Zhab...