The fluorescent derivatization of tryptophan metabolites (xanthurenic acid, nicotinic acid, picolinic acid, and 3-hydroxyanthranilic acid) by the catalytic activity of horseradish peroxidase (HRP) was investigated in the presence of excess H(2)O(2). Non-fluorescent xanthurenic acid (XA) and nicotinic acid (NA) were converted into a fluorescent compound with maximum excitation and emission wavel...

Stoichiometry and stability of antitumor ruthenium(II)-η-p-cymene complexes of picolinic acid and its 6-methyl and 6-carboxylic acid derivatives were determined by pHpotentiometry, H NMR spectroscopy and UV/Vis spectrophotometry in aqueous solution in the presence or absence of coordinating chloride ions. The picolinates form exclusively monoligand complexes in which they can coordinate via the...

Hankes and Henderson (I), Gholson et al. (2), and Gholson and Henderson (3) demonstrated that nL-tryptophan-7cu-14C was metabolized by the rat to r4C02 via acetate-1-r4C. Subsequently, Gholson et al. (4) indicated that 3-hydroxyanthranilic acid was an intermediate in the major pathway for the degradation of the benzene ring of tryptophan. Further experiments in viva have provided evidence that ...

The 2-carbene tautomer of pyridine (I), azacyclohexanetriene2-ylidene (II), was first proposed by Hammick1 70 years ago to explain the facile decarboxylation of 2-picolinic acid. Recent theoretical calculations2 have shown that II has energy about 4550 kcal‚mol-1 higher than I and that the transition state for the I to II rearrangement lies ca. 85 kcal‚mol-1 above I. Accordingly, the I to II ta...

Ethylene is an important phytohormone that promotes the ripening of fruits and senescence of flowers thereby reducing their shelf lives. Specific ethylene biosynthesis inhibitors would help to decrease postharvest loss. Here, we identify pyrazinamide (PZA), a clinical drug used to treat tuberculosis, as an inhibitor of ethylene biosynthesis in Arabidopsis thaliana, using a chemical genetics app...

Cu-catalyzed O-arylation of phenols with aryl iodides and bromides can be performed under mild condition in DMSO/K(3)PO(4) with use of picolinic acid as the ligand for copper. This method tolerates a variety of functional groups and is effective in the synthesis of hindered diaryl ethers and heteroaryl ethers.

In view of the importance of picolinic acid (Pa) in preventing cell growth and arresting cell cycle, attempts were made to design, synthesize and characterize two new Pa based tetradentate ligands (DPPTR and DPPTY) with a modified procedure. The procedure reported here avoids by-products and provides better yield and purity.

Reaction of PdCl2 with N,N-bis-(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy) afforded a mononuclear complex [(bdppmapy)PdCl2] (). Compound was characterized by elemental analysis, IR, (1)H, (13)C and (31)P NMR, electrospray ion mass spectra (ESI-MS) and X-ray single crystal crystallography. The Pd(ii) center in is chelated by bdppmapy, showing a cis-square planar geometry. With the assi...

2-aminophenol (2-AP) is a toxic nitrogen-containing aromatic pollutant. Burkholderia xenovorans LB400 possess an amn gene cluster that encodes the 2-AP catabolic pathway. In this report, the functionality of the 2-aminophenol pathway of B. xenovorans strain LB400 was analyzed. The amnRJBACDFEHG cluster located at chromosome 1 encodes the enzymes for the degradation of 2-aminophenol. The absence...