Activated enol ethers derived from esters or the dinitrile of malonic acid, or from pentane-2,4-dione were treated with hydrazine hydrate. The structures of the obtained products - pyrazoles 5 - were studied with a focus on tautomerism and supramolecular structure. A reverse addition of the reagents led to the isolation of two novel products, namely bis-enehydrazines 6 with an unsymmetrical arr...

We present a numerical solution of the chlorine-dioxide–iodine–malonic-acid reaction-diffusion system in two dimensions in a boundary-fed system using a realistic model. The bifurcation diagram for the transition from nonsymmetry-breaking structures along boundary feed gradients to transverse symmetry-breaking patterns in a single layer is numerically determined. We find this transition to be d...

Various factors affecting the yields of luteoskyrin, a hepatotoxic mycotoxin, and related pigments in the liquid medium were studied. Maximal yields of luteoskyrin (0.13% by isolation) and of other pigments were attained in the late phase of the cultivation. The yield of the pigment was increased by supplying malt extract, malonic acid, glutamic acid, or asparagine. A useful material for prepar...

The hydrometallurgical method of copper leaching from scrap electronics is commonly undertaken using pulverized printed circuit boards. Though studies on the use organic acids like citric and oxalic for removal are well documented, those malonic acid rare. Herein, we report investigation efficiencies mixtures hydrogen peroxide unpulverized PCB by Box-Behnken design theoretical determination mos...

organic academia are diverse group of disorders characterized by abnormal degredation of specific amino acid in the specific catabolism due to an enzymeactivity defect which mainly due to enzyme deficiency. the majority of the classic organic acid disorders are caused by abnormal catabolism of branched-chain amino acids like lysine. maple syrup urine disease (msud), propionic acidemia, methylma...

Experimental methods and equations are given for calculating the concentration and dissociation constant of each acid or base in a mixture by use of its complex pH titration curve. The principle is illustrated by means of experimental data for malonic acid. This problem is important as an aid in determining the nature of the acids and bases in p~ant and animal fibers, fruits, culture media , pu...

Vibrational spectroscopy can give useful informa tian, both structural and dynamical, about phase transitions in molecular crystals. In particular, the data concerning the mechanism of the transformation at molecular level can be obtained. This is illustrated by examples of pure van der Waals crystals such as 3,5-dichloropyridine and 4-methylpyridine, hydrogen bonded malonic acid, inorganic fer...

An N,N'-dioxide/scandium(III) complex catalyzed, highly efficient conjugate addition of malonic esters to enynes is described. A range of trisubstituted 1,2-allenyl ketones were obtained in high yields (up to 99 %) with good d.r. (up to 95/5) and excellent ee values (97 %-99 %). Moreover, the products could be easily transformed into chiral furan and 5-hydroxypyrazoline derivatives, both of whi...