(1) A new type of Escherichia coli mutant which shows increased sensitivity to methyl methane sulfonate but not to UV light or to gamma rays was isolated after mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine.
(2) Sec-alpha-halo-nitro compounds are active antibacterial and antifungal agents, and the sec-bromo derivatives are the most active and stable.
(3) A series of 2-styryl-5-nitro-1-vinylimidazoles carrying alkylaminomethyl or amidino functions in the 4 position of the styryl ring was prepared and evaluated for antitrypanosomal activity in mice infected with Trypanosoma rhodesiense.
(4) The effects of Ng-nitro-L-arginine were reversed by L-arginine.
(5) The best compound was trans-alpha-[[(4-bromotetrahydro-2H-pyran-3-yl) amino]methyl]-2-nitro-1H-imidazole-1-ethanol (18), which, due to its activity and log P value, is a candidate for additional in vivo studies.
(6) In addition, cell lines exhibiting increased resistance to N-methyl-N'-nitro-N-nitrosoguanidine have been derived from a cell line expressing the Ada protein methylphosphotriester repair function.
(7) It is likely that nitro substitution at the 6-position of 5-MeC interferes with the structural requirements of the 1,2-diol-3,4-epoxide which are necessary for specific DNA interactions.
(8) After mutagenesis with N-methyl-N'-nitro-N-nitrosoguanidine and penicillin selection, two kinds of B(12) transport mutant were isolated from this strain.
(9) AOAA-induced (0.25 mumol-1 mumol) striatal lesions in adult rats displayed excitotoxic characteristics and could be prevented by the N-methyl-D-aspartate (NMDA) receptor antagonists (-)-2-amino-7-phosphono-heptanoate (AP7; 0.25 mumol) or kynurenate (KYNA; 0.5 mumol), but not by the non-NMDA antagonist 2,3-dihydroxy-6-nitro-7-sulphamoyl-benzo(F)quinoxaline (NBQX; 0.25 mumol).
(10) The oxidation of the anion radical intermediate by O2 to the parent nitro compound is proposed to account for the well-known O2 inhibition of microsomal nitroreductase.
(11) The complexes are produced by attachment of a carbon of the butenolide ring to an aromatic carbon of the nitro compound with formation of a charge-delocalized cyclohexadienate anion.
(12) With these compounds, the spin density at the nitro group was greater than with nifurtimox, nitrofurazone and nitrofurantoin.
(13) Amino and nitro groups, introduced at position-4 of estrone 3-methyl ether were particularly carcinostatic, a property not shared by 4-bromoestrone 3-methyl ether.
(14) The labeled egg albumin was hydrolyzed in 6N HCl at 110 degrees C for 24 h. The hydrolysate was lyophilized, derivatized with 4-fluoro-7-nitro-2,1,3-benzoxadiazole, a fluorogenic reagent for amines, and subjected to HPLC.
(15) Nitroreductases must therefore be able to compete successfully with molecular oxygen for the MISO nitro radical-anion in such tissues.
(16) It has been suggested that under aerobic conditions the aziridine ring is primarily responsible for aerobic toxicity, whereas under hypoxic conditions, the aziridine moiety combined with a reduced 2-nitro moiety produces a bifunctional agent (I. J. Stratford et al., Br.
(17) N omega-Nitro-L-arginine methyl ester (NAME) (10(-5) to 5 x 10(-4) M) abolished ijps in both tissues, an effect overcome by 10(-3) M L-arginine but not D-arginine.
(18) The incidence, number, and histological types of gastric cancers induced by N-methyl-N'-nitro-N-nitrosoguanidine and the tissue norepinephrine concentration of the gastric wall were investigated in spontaneously hypertensive rats and in control Wistar Kyoto rats and Wistar rats.
(19) A nitroreductase enzyme has been isolated from Walker 256 rat carcinoma cells which can convert 5-(aziridin-1-yl)-2,4-dinitrobenzamide (CB 1954) to a cytotoxic DNA interstrand crosslinking agent by reduction of its 4-nitro group to the corresponding hydroxylamino species (Roberts JJ et al., Biochem Biophys Res Commun 140: 1073-1078, 1986; Knox RJ et al., Biochem Pharmacol 37: 4661-4669, 1988).
(20) In contrast, nordihydroguaiaretic acid, metyrapone, NG-monomethyl-L-arginine, and nitro-L-arginine all attenuated the relaxation to acetylcholine; however, indomethacin had no effect on acetylcholine-induced relaxations.