(1) Methods were developed for the conversion of substituted benzoic acids (1-4) to give benzopyrazines (12-16 and 21) and of substituted pyridin-2-carbamates (23, 38, and 41) to give 2-aminopyrido[3,4-b]pyrazin-7-ylcarbamates (32 and 36) and pyrido[3,4-e]-as-triazin-7-ylcarbamates (47 and 50).
Quinoxaline
Definition:
(n.) Any one of a series of complex nitrogenous bases obtained by the union of certain aniline derivatives with glyoxal or with certain ketones.
Example Sentences:
(1) 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).
(2) Oxythioquinox, Plictran (tricyclohexylhydroxytin), Nissol [2-fluoro-N-methyl-N-(1-naphthyl)acetamide], and chlordimeform are examples of quinoxaline, organotin, organofluorine, and formamidine acaricides, respectively.
(3) Addition of the non-N-methyl-D-aspartate (non-NMDA) selective antagonist 6-cyano-7-nitro-quinoxaline-2,3-dione (CNQX) to the slice surface near the recording electrode resulted in a rapid (within 30-45 s) suppression of the EPSP.
(4) A significant stimulation in liver microsomal enzymes occurred after 2,3-dimethyl quinoxaline and 2,3-diphenyl quinoxaline treatments; these changes were associated with increases in cytochrome P-450 level and in RNA and protein contents of the microsomal fraction.
(5) Synthetic heterocyclic quinones (107 samples) consisting of o- and p-quinoline quinones, o-isoquinoline quinones and p-quinoxaline quinones as well as o- and p-naphthoquinones (3 samples) were tested for their inhibitory activities against avian myeloblastosis virus reverse transcriptase (AMV-RT) and cytotoxic activities against mouse lymphoblastoma L5178Y cells.
(6) Quinoxalines and kynurenates antagonized in a non-competitive manner L-glutamate-induced contraction.
(7) The alpha-amino-3-hydroxy-5-methyl-4-isoxazolepripriate (AMPA)-receptor blocker, 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F) quinoxaline (NBQX), administered as an intravenous dose of 29.76 and 89.29 mumol kg-1 (10 & 30 mg kg-1), which is sufficient to block seizures and protect against ischaemic brain damage, did not inhibit spreading depression.
(8) Second, the sialic acids content is measured fluorometrically using their precolumn conversion to quinoxaline derivatives.
(9) 2-Amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx) is a potent bacterial promutagen and carcinogen, formed when beef is cooked.
(10) These cell wall skeletons also bound 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), 2-amino-5-phenylpyridine (Phe-P-1), IQ, 2-amino-3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQX).
(11) Their ability to suppress the antilipolytic effect of an alpha-2 agonist [UK-14,304 (5-bromo-6-(2-imidazolin-2-ylamino)-quinoxaline)] on isolated fat cells was equivalent.
(13) The tumorigenic activities of four representative heterocyclic amine food pyrolysates, 2-amino-6-methyldipyrido[1,2-a:3',2'-d]imidazole (Glu-P-1), 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2-amino-3,8-dimethylimidazo[4,5f]quinoxaline (MeIQx), and 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), were assessed in the neonatal male B6C3F1 mouse and were compared with that of the potent human carcinogen, 4-amino-biphenyl (4-ABP).
(14) The chemotherapeutic effect of di-N-quinoxaline oxide derivatives--quinoxidine and diaxidine, as contrasted to that of carbenicillin and hentamycin with their 3- and 10-day application, was studied on a model of a burn in mice infected with Pseudomonas eruginosa.
(15) Postsynaptic responses in NL were blocked completely, in a concentration-dependent and reversible fashion, by bath application of the broad-spectrum excitatory amino acid (EAA) antagonist kynurenic acid, the 'non-NMDA' EAA receptor antagonists 6,7-dinitroquinoxaline-2,3-dione (DNQX) and 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (NBQX), and the EAA agonists domoic acid, kainic acid, alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA), and quisqualic acid.
(16) Individual 2-carboxylic acids derived from imidazo[1,2-a]quinolines, imidazo[1,2-a]quinoxalines, imidazo[1,2-a]quinoxalinones, pyrrolo[1,2-a]quinoxalinones, pyrrolo[2,3-a]quinoxalinones, and imidazo[2,1-b]benzothiazoles showed iv activities up to 10(3) times as potent as DSCG and many of them showed significant oral activity.
(17) An excellent correlation was observed between inhibitory potencies of the quinoxaline derivatives against kainate and AMPA currents, in support of the contention that in this preparation these two agonists act at a single site.
(18) Two members of the quinoxaline antibiotic family, echinomycin and triostin A, form crystals complexed to a DNA fragment with the sequence d(CpGpTpApCpG).
(19) The activities of 1,2-dimethylhydrazine, dimethylnitrosamine, and 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline in the Dlb-1 assay more accurately reflect their carcinogenic potential than do many in vitro bioassays.
(20) The activation of three other food mutagens, 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) and aflatoxin B1 (AFB1) was also inhibited by these fatty acids.