Reactive oxygen species induce oxidative damage in DNA precursors, i.e. dNTPs, leading to point mutations upon incorporation. Escherichia coli mutT strains, deficient in the activity hydrolysing 8-oxo-7,8-dihydro-2'-deoxyguanosine 5'-triphosphate (8-oxo-dGTP), display more than a 100-fold higher spontaneous mutation frequency over the wild-type strain. 8-oxo-dGTP induces A to C transversions wh...

Previous studies have established that 4-hydroxy-2-nonenal is a lipid hydroperoxide-derived aldehydic bifunctional electrophile that reacts with DNA and proteins. However, it has now been recognized that 4-oxo-2-nonenal is also a major product of lipid hydroperoxide decomposition. Furthermore, 4-oxo-2-nonenal is more reactive than 4-hydroxy-2-nonenal toward the DNA-bases 2'-deoxyguanosine, 2'-d...

The ubiquity of vanadium oxo complexes in the V+ and IV+ oxidation states has contributed to a comprehensive understanding of their electronic structure and reactivity. However, despite being predicted to be stable by ligand-field theory, the isolation and characterization of a well-defined terminal mononuclear vanadium(III) oxo complex has remained elusive. We present the synthesis and charact...

GTP cyclohydrolase I (GTPCH1) catalyzes the conversion of GTP to dihydroneopterin 3'-triphosphate. We found that an 8-oxoguanine derivative of GTP (8-oxo-GTP) strongly bound to GTPCH1 from Thermus thermophilus HB8 (tGTPCH1) as a competitive inhibitor. The affinity of 8-oxo-GTP was three orders of magnitude greater than that of GTP. These results suggest that 8-oxo-GTP is a transition state anal...

Redox-inactive metal ions play pivotal roles in regulating the reactivities of high-valent metal-oxo species in a variety of enzymatic and chemical reactions. A mononuclear non-heme Mn(IV)-oxo complex bearing a pentadentate N5 ligand has been synthesized and used in the synthesis of a Mn(IV)-oxo complex binding scandium ions. The Mn(IV)-oxo complexes were characterized with various spectroscopi...

Six N-substituted-phenyl 4-oxo-4H-chromene-3-carboxamides, namely N-(2-nitro-phen-yl)-4-oxo-4H-chromene-3-carboxamide, C16H10N2O5 (2b), N-(3-meth-oxy-phen-yl)-4-oxo-4H-chromene-3-carboxamide, C17H13NO4, (3a), N-(3-bromo-phen-yl)-4-oxo-4H-chromene-3-carboxamide, C16H10BrNO3, (3b), N-(4-methoxy-phen-yl)-4-oxo-4H-chromene-3-carboxamide, C17H13NO4, (4a), N-(4-methyl-phen-yl)-4-oxo-4H-chromene-3-car...

  Quinolone antibacterial agents are currently used for the treatment of various bacterial infections. The nature of functional group at the 7 position of the quinolone ring system is known to have strong influence on the spectrum and extent of in vitro antibacterial activity. Accordingly, a series of N-L2- oxo-2-(2- furyl) and N-[2- oxyimino (2- furyl) ethyl] piperazinyl quinolone derivatives...

In the last decades, organic azides haven proven to be very useful precursors in organic chemistry, for example in 1,3-dipolar cycloaddition reactions (click-chemistry). Likewise, azides can be introduced into graphene oxide with an almost intact carbon framework, namely oxo-functionalized graphene (oxo-G₁), which is a highly oxidized graphene derivative and a powerful precursor for graphene th...

7-(D-5-Amino-5-carboxy-valeramido)-3-(acetylhydrazido)-8-oxo-5-thio-1-azabicyclo [4,2,0]-oct2-ene-2-carboxylic acid (1). 7-(D-5-Amino-5-carboxy-valeramido)-3-(substitutedarylacetylhydrazido)8-oxo-5-thio-1-azabicyclo[4,2,0]-oct-2-ene-2-carboxylic acid.(2-5). 7-(D-5Amino-5carboxyvaleramido)3(2'substituted aryl-3'-chloro-4'-oxo-azetidin-1'-yl)-acetylamino]-8-oxo-5-thio-1azabicyclo[4,2,0]-oct-2-ene...

patch-clamp technique, effects of the potent muscarinic agonist oxotremorine methiodide ( oxo-M ) on voltage-activated Ca 2/ I N T R O D U C T I O N channel currents were investigated in acutely dissociated adult Acetylcholine (ACh) is the principal transmitter at both rat intracardiac neurons. In all tested neurons oxo-M reversibly preganglionic and postganglionic synapses in parasympainhibite...