The mol-ecule of the title compound, C(15)H(14)N(4)O(3), is completed by the application of crystallographic twofold symmetry, with the carbonyl group lying on the rotation axis. The mol-ecule is close to planar: the greatest deviation of a torsion angle from 0° is 7.3 (2)° about the bond linking the phenol ring to the rest of the mol-ecule. An intra-molecular O-H⋯N(imine) hydrogen bond is form...

The complexation equi li bria of zinc(lI ) wi th 2-hydroxy-IAnaphthoquinone. 5-hydroxyIA-naphthoquinone and 5.8-dihydroxyIA-naphthoquinone have been studied spectrophotometri call y as a function of pH in 50~ (1'/1') ethanol-water medium at 25°C and an ionic strength of 0.1 M NaCI04 . The spectral study of the complexati on reactions has been carried out in solutions contain ing equimolar conce...

An efficient and convenient strategy for the enantioselective synthesis of enantiomerically enriched 10-ethyl-7,8-dihydro-γ-ionone isomers (R)-(+)-7, and (S)-(-)-7 are described utilizing a lipase mediated resolution protocol, and reductive elimination of the secondary allylic alcohol as the key step. The enantioselective and diastereoselective lipase kinetic acetylation of 4-hydroxy-γ-ionone d...

Ammonium sulfate is one of the subsidiary components in the stealth liposome structure. The ratio of ammonium ion bound to liposome sphere to ammonium ions outside the liposome plays an important role in drug delivery formulation; accordingly, in order to quantify the ammonium ion in the liposome structure, a rapid and sensitive method was validated using a conductivity detector. Through this m...

background: surface water and groundwater pollution with various forms of nitrogen such as ammonium and nitrate ions is one of the main environmental risks. the major objectives of this study were to evaluate the capacity of natural zeolite (clinoptilolite) to remove no3- and nh4+ from polluted water under both batch and column conditions. methods: the laboratory batch and column experiments we...

to study the effect of type and different nitrogen fertilizers on controlling egyptian broomrape, field and greenhouse studies based on randomized complete block with three replications, were conducted at ferdowsi university of mashhad. greenhouse study treatments were consisted of ammonium nitrate, ammonium sulfate and urea each of which applied at four rates (75, 150, 300 and 350 kg/ha). fiel...

DNA microarray analysis of gene expression in steady-state chemostat cultures limited for potassium revealed a surprising connection between potassium and ammonium: potassium limits growth only when ammonium is the nitrogen source. Under potassium limitation, ammonium appears to be toxic for Saccharomyces cerevisiae. This ammonium toxicity, which appears to occur by leakage of ammonium through ...

nitrate and ammonium forms of nitrogen are being applied to improve plant growth and uptake of other nutrients. given that the effect of application of different nitrate to ammonium ratios accompanied by other fertilizers (i.e. fe, mn and zn) has not been studied on wheat growth as well as uptake of fe, mn and zn, three glasshouse pot studies were conducted with factorial arrangement of treatme...