A new, stepwise synthesis of calix[4]phyrins is described. It relies on the condensation of a ketone with pyrrole to form a dipyrromethane containing a quaternary carbon center that is subsequently condensed with an aromatic aldehyde. This methodology, in contrast to the previous rational approach described by this group (involving formation of a trisubstituted dipyrromethane via the condensati...

A multicomponent reaction of indane-1,3-dione, an aldehyde and an amine-containing aromatic compound leading to the formation of indenopyridine-based heterocyclic medicinal scaffolds has been investigated. It was found that the yields significantly improve when oxygen gas is bubbled through the reaction mixture, facilitating the oxidation of the intermediate dihydropyridine-containing compounds...

An aldehyde dehydrogenase (ALDH) with properties identical to those of the NADP+-dependent, tumor-associated aldehyde dehydrogenase appearing during rat hepatocarcinogenesis has been identified in normal rat urinary bladder. Like the tumor-associated aldehyde dehydrogenase, bladder NADP+-ALDH is cytosolic and preferentially oxidizes benzaldehyde-like aromatic aldehydes. Bladder ALDH is also ext...

The effect of frozen storage on lipid peroxidation in Atlantic mackerel (Scomber scombrus) stored for up to 26 weeks at -10 or -80°C (control), with and without green tea antioxidants, was investigated. Hydroperoxides (PV) and aldehydes (TBARS) were measured by HPLC and LC-MS and hexanal by GC. There was an increase in peroxide value which was associated with an increase in aldehydes, followed ...

Alkoxy (R1C(R2)(R3)O•) and Carbonyl (RC(•)O) radicals are important intermediates in the degradation chain of hydrocarbons. Both classes of radicals are subject to competing reaction chan-nels leading to different products which exhibit different ozone formation potentials: Alkoxy radicals (1) Reaction with O2 (kO2, => aldehyde/ketone + HO2); (2) thermal decomposition (kdis, => aldehyde/ketone ...

Bestmann ylide [(triphenylphosphoranylidene)ketene] acts as a chemical linchpin that links nucleophilic entities, such as alcohols or amines, with carbonyl moieties to produce unsaturated esters and amides, respectively. In this work, the formation of α,β,γ,δ-unsaturated esters (dienoates) is achieved through the coupling of Bestmann ylide, an alcohol and an α,β-unsaturated aldehyde. Primary an...

Simultaneous condensation reaction of thiocarbohydrazide with simple aromatic aldehyde and highly reactive ferrocenecarboxaldehyde resulted unusual unsymmentric Schiff bases associated multi metal ion sensing property. Spectral characterization methods indicate the formation new materials. Guest- host relationship established between various ions receptors changes electronic spectra drastically...

A central question in lignin biosynthesis is how guaiacyl intermediates are hydroxylated and methylated to the syringyl monolignol in angiosperms. To address this question, we cloned cDNAs encoding a cytochrome P450 monooxygenase (LsM88) and a caffeate O-methyltransferase (COMT) from sweetgum (Liquidambar styraciflua) xylem. Mass spectrometry-based functional analysis of LsM88 in yeast identifi...

The guanosine hydrazide 1 yields a stable supramolecular hydrogel based on the formation of a guanine quartet (G-quartet) in presence of metal cations. The effect of various parameters (concentration, nature of metal ion, and temperature) on the properties of this gel has been studied. Proton NMR spectroscopy is shown to allow a molecular characterization of the gelation process. Hydrazide 1 an...