2-Ethylthio-6- pyrazine

Treatment of 3-hydroxy-2,3-dimethylperhydropyrido[l,2-a]pyrazine-l,4-dione with ethanethioi in CHC13 in the presence of ZnCl2 gave the 3-ethylthio derivative (74CB2804). Heating l-imino-l,4-dihydropyrido[l,2-a]-pyrazin-5-ium bromide in 48% HBr gave l-oxo-l,2-dihydropyrido [l,2-a]pyrazin-5-ium bromide [67JCS(C)2391]. 

Chloro-3-propionylpyrazine (164, R = Cl) gave 2-ethylthio-3-propionyl-pyrazine (164, R = SEt) (EtSH, EtONa, EtOH, 20°C, 4 h 87%).815... 

Cyano-3-diallylamino-2-pyrazinecarboxamide 5-Cyano-3-diethylamino-2-pyrazinecarboxamide 3-Cyano-5,6-diphenyl-2-pyrazinecarboxamide 5-Cyano-3-dipropylamino-2-pyrazinecarboxamide 5-Cyano-3-ethylthio-2-pyrazinecarboxamide 5-Cyano-3-isobutylamino-2-pyrazinecarboxamide 5-Cyano-3-isopropylthio-2-pyrazinecarboxamide 2- (1-Cyano-1 -methylethyl)pyrazine 2- Cyanomethyl-3 -phenylpyrazine 2-(l-Cyano-2-methylpropyl)pyrazine 2- Cyanomethylpyrazine... 

Ethylthio-2-pyrazinecarbonitrile 6-Ethylthio-2-pyrazinecarbonitrile 6-Ethylthio-2-pyrazinecarbothioamide 3-Ethylthio-2-pyrazinecarboxamide 6-Ethylthio-2-pyrazinecarboxamide 3-Ethylthio-2-pyrazinecarboxylic acid 6-Ethylthio-2-pyrazinecarboxylic acid 3-Ethylthio-2,5-pyrazinedicarboxamide 2-Ethylthiopyrazine 1-oxide 2-Ethyl-3,5,6-trimethylpyrazine 2-Ethyl-3,5,6-triphenylpyrazine 2-Ethyl-3-vinylpyrazine 2-Ethynyl-3,6-dimethylpyrazine 2-Ethynyl-3-methylpyrazine 2-Fluoro-5,6-dimethoxy-3-methylpyrazine 2- Fluoro- 5,6-dimethoxypyrazine 2-Fluoro-3,6-dimethylpyrazine 2-Fluoro-3-(l-hydroxyethyl)pyrazine 2-Fluoro-3-iodopyrazine 2-Fluoromethyl-5-methyl-3,6-diphenylpyrazine 2- Fluoro- 5-phenylpyrazine 2-Fluoro-3-phenylthiopyrazine... 

Halogenopyrazines react with alkylthiolate ions to give alkylthiopyrazines, by replacement of one or, in some cases, two halogeno substituents the reaction is usually carried out at reflux or at elevated temperatures in sealed tubes. The following pyrazines have been prepared by these methods from the chloropyrazines unless otherwise specified 2-ethylthio and 2-isopropylthio (668a) 2-methyl-3-methylthio (735, 844,977) 2-methyl-5(and 6)-methylthio (735) 2,5-dimethyl-3-methyl(ethyl,... 

The following nitriles have been used to prepare carboxypyrazines 2-cyano-3-phenyl [NaOH/ethylene glycol/reflux (1274) or heated with H2S04/NaN02 (1024)] 3-cyano-2,5-dimethyl (NaOH/EtOH/reflux) (1015) 3-cyano-2,5-diphenyl (NaOH) (286) 2,3-dicyano [NaOH/EtOH (354) aq. KOH/EtOH (353) NajOj (357)] 2,6-dicyano (5% NaOH/10072h)(865) 23-dicyano-5,6-dimethyl(Na202) (357) 2-cyano-6-ethylthio(propylthio or phenylthio) (NaOH/EtOH/reflux) (992) 2hydrochloric acid to 2-(3 -carboxy-3 -phenylpropyl)pyrazine (731). 

Carbamoylpyrazine was methylated to 3-carbamoyl-l -methylpyrazinium iodide by methyl iodide in methanol at reflux (138) and by methyl iodide in dimethyl sulfoxide at room temperature (666) under the latter conditions the rate of methylation relative to pyrazine was 0.53 (666). 3-Carbamoyl-l-methylpyrazinium iodide reacted with liquid ammonia at — 40° to give 2-amino-5-carbamoyl-l-methyl-1,2-dihydropyrazine (46) (609). With nitromethide ions in liquid ammonia, none of the carbon addition reaction was found (721), but with ethanethiolate ion in liquid ammonia it gave 5-carbamoyl-2-ethylthio-l-methyl-1,2-dihydropyrazine (721). 2-(4 -Morpholino)carbonylpyrazine with methyl iodide gave 3-(4 -morpholino)-carbonyl-1-methylpyrazinium iodide (870). 

The most known designer drugs are carphedone 4-chloro-2,5-dimethoxyphenethylamine (2C-C) i 5-6-(5-chloropyridin-2-yl)-7-oxo-6,7-dihydro-5H-pyrrolo[3,4-b]pyrazin-5-yM-methylpiperazine-l-carboxylate (zopiclone or Z-drug) 4-(N,N-dimethylamino sulfonyl)-7-fluoro-2,l,3-benzoxadiazole (DBD-F) dimethyltryptamine (DMTA) diphenydramine 4-ethyl-2,5-dimethoxyphenethylamine (2C-E) 4-ethylthio-2,5-dimethoxyphenethylamine (2C-T-2) 4-fluoroamphetamine (4-FMP) indan-2-amine 4-iodo-2,5-dimethoxyphenethylamine (2C-I) 1 -(4-iodo-2,5-dimethoxyphenyl)propan-2-amine (DOI) 4-isopropylthio-2,5-dimethyoxyphenethylamine (2C-T-4) meperidine 2-methylamino-l-(3,4-methylenedioxyphenyl)butan-l-one (Bk-MBDB) l-(3,4-methylenedioxybenzyl)piperazine (MDBP) 1 -(3,4-methylenedioxyphenyl)butan-2-amine (BDB) N-methyl-3,4-methylenedioxymethamphetamine (MMDA-2) N-methyl-1 -(3,4-methylenedioxyphenyl)butan-2-amine (HMDMA) N-methyl-l-(3,4-methylenedioxyphenyl)butan-3-amine (HMDMA) methylphenidate 4-methoxymethamphetamine (PMMA) l-(4-methoxyphenyl)piperazine (4-MPP) 2-(6-methyl-2-p-tolylimidazol[l,2-9]pyridine-3-yl)acetamide (zolpidem) normeperidine 4-phenylbutylamine (4-PBA) 3-phenyl-1-peopyTamine (3-PPA) and 2,4,6-trimethoxyamphetamine (TMA-6). 

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