the ethyl acetate partition of dried methanolic extract of aerial parts of euphorbia microsciadia (euphorbiaceae) afforded three pentacyclic triterpenes, betulinic acid (1) from lupane type, oleanolic acid (2) from oleane type and ursolic acid (3) from ursane type triterpenes that are reported for the first time in this plant. these three compounds were structurally compared through their mass ...

A convenient and efficient direct protocol for the preparation of antibacterial azo dyes by the reaction of 2-naphthol with aromatic amines in the presence of catalytic amount of N-methyl-2-pyrrolidonium hydrogen sulfate ([H-NMP]HSO4) was carried out under solvent free conditions. This method has some advantages such as: easy work-up and easy separation of catalyst from the reaction mixture. Th...

It was found 1 that Ro ... 0 distances in cyclic dimers of p-substituted benzoic acids in the crystalline state do not follow the Hammett rule. The Ro ... 0 values often serve as an approximate measure of hydrogen bond strength.2 Since substituent constants op and R0 ... 0 express the Bronsted and the Lewis acidity of the carboxylic group in solution and in the crystalline state, respectively, ...

A new superacid, H(CB11H6X6) (where X = chlorine or bromine), whose conjugate base is the exceptionally inert CB11H6X6- carborane anion, separates Bronsted acidity from oxidizing capacity and anion nucleophilicity in a manner not previously achieved. Reaction of this superacid with C60 gives HC60+ as a stable ion in solution and in the solid state. In a separate experiment, an oxidant was devel...

T H E NATURE of pyridine adsorption by acidand base-saturated montmorillonite from Otay, California (A.P.I, no. H-24) was studied by infrared adsorption. The spectrum for chemisorbed pyridine was found to be distinctively different from physically adsorbed pyridine; the latter gave a spectrum very similar to liquid pyridine. Upon exposure of the clay films to pyridine at low vapor pressures, on...

Levulinic acid (LA) is one of the top twelve chemicals listed by US Department Energy that can be derived from biomass. It serves as a building block and platform chemical for producing variety chemicals, fuels materials which are currently produced in fossil based refineries. LA key strategic chemical, fuel grade plastic substitutes its catalytic conversion. derivatisation to various product s...

The ethyl acetate partition of dried methanolic extract of aerial parts of Euphorbia microsciadia (Euphorbiaceae) afforded three pentacyclic triterpenes, betulinic acid (1) from lupane type, oleanolic acid (2) from oleane type and ursolic acid (3) from ursane type triterpenes that are reported for the first time in this plant. These three compounds were structurally compared through their mass ...

The ethyl acetate partition of dried methanolic extract of aerial parts of Euphorbia microsciadia (Euphorbiaceae) afforded three pentacyclic triterpenes, betulinic acid (1) from lupane type, oleanolic acid (2) from oleane type and ursolic acid (3) from ursane type triterpenes that are reported for the first time in this plant. These three compounds were structurally compared through their mass ...