Z. Naturforsch. 55 b, 1037-1044 (2000); received July 28, 2000 Nonadentate Ligand, Schiff Base, Nickel The tetrapodal pentaamine 2,6-C5H3N[CMe(CH2NH2)2l2 (pyN_u 1) readily reacts with four equivalents of 2-hydroxyphenyl-substituted carbonyl compounds, such as (i) 2-hydroxybenzaldehyde, (ii) 2,4-dihydroxybenzaldehyde, (iii) 3,5-di-rm-butyl-2-hydroxybenzaldehyde, and (iv) 2-hydroxyacetophenone, t...

To determine whether microbial chemosensors can be used to find new or better biocatalysts, we constructed Escherichia coli hosts that recognize the product of a biocatalytic conversion through the transcriptional activator NahR and respond by expression of a lacZ or tetA reporter gene. Equipped with a benzaldehyde dehydrogenase (XylC from Pseudomonas putida), the lacZ-based host responded to t...

A series of difunctionalized 4-hydroxybenzaldehyde derivatives were designed, synthesized and evaluated as cholinesterase (acetylcholinesterase (AChE) and butyrylcholinesterase (BChE)) inhibitors. The results demonstrated that all the compounds had more potent AChE and BChE inhibitory activities than galanthamine-HBr, one of the best cholinesterase inhibitors known so far. The inhibition mechan...

Extracts were obtained from molasses, a byproduct of the sugar industry, via a number of chromatographic steps. Their antioxidant capacity was studied, including the inhibitory effect upon DNA oxidative damage; the phenolic compound profile thereof was ascertained as well. Two extracts exhibited significant antioxidant features, expressed by their capacity to decolorize ABTS radical cation and ...

Three volatile components, namely benzoic acid ethyl ester (1), 2,6-di-tert-butyl-p-benzoquinone (BHT-quinone) (2), and 3,5-di-tert-butyl-4-hydroxybenzaldehyde (BHT-CHO) (3), were detected from the gas in the capsules of Asclepias physocarpa by means of GC/MS analysis. BHT-quinone and BHT-CHO as organic pollutants are the degradation products of the antioxidant 2,6-di-tert-butyl-4-methylphenol ...

The NMR spin lattice relaxation of various aldehydes has been investigated. The experimental values of NMR spin lattice relaxation time T1 of benzaldehyde, anisaldehyde, o-cholorobenzaldehyde and p-hydroxybenzaldehyde have been correlated with the calculated value of N M R spin lattice relaxation time T1 obtained using various equations for dielectric relaxation time τ. It has been concluded th...