2-Chloro-3- 6- isobutylpyrazine

Chloro-3-isobutylpyrazine 4-oxide gave 3-isobutyl-2( I // )-pyrazinone 4-oxide (111, R = Hu ) (5 M NaOH, reflux, 2 h 39%) 86 2-chloro-3-phenylpyrazine 4-oxide gave 3-phenyl-2( I //(-pyrazinone 4-oxide (111, R = Ph) (KOH, H20—EtOH, reflux, 1 h 30%) 1290 also analogues likewise.1290... [Pg.158]

Benzyloxy-5-chloro-6-hydroxymethyl-3-isobutylpyrazine 4-oxide gave 2-benzyloxy-5-chloro-3-isobutyl-6-[(tetrahydropyran-2-yloxy)methyl]pyrazine 4-oxide (150) (3,4-dihydro-2//-pyran, TsOH.H20, CH2C12, 20°C, 1 h 95%).848... [Pg.214]

Acetoxy methyl- 5-phenyl- 2(1 77)-pyrazinone 5-Acetoxy methyl- 3-phenyl- 2(1 77)-pyrazinone 2-(l-Acetoxy-2-methylpropyl)-3-chloro-5-isobutylpyrazine... [Pg.354]

Chloro-3-isobutyl-6-methylpyrazine 1-oxide 2-Chloro-6-isobutyl-3-methylpyrazine 1-oxide 2-Chloro-6-isobutyl-3-methylpyrazine 4-oxide 2-Chloro-3-isobutyl-5-phenylpyrazine 2-Chloro-3-isobutylpyrazine... [Pg.390]

Chloro-5-isobutylpyrazine 6-Chloro-5-isobutyl-2-pyrazinecarbothioamide 6-Chloro-5-isobutyl-2-pyrazinecarboxamide 2-Chloro-3-isobutylpyrazine 4-oxide 2-Chloro-5-isopentyl-3,6-dimethylpyrazine 2-Chloro-3-isopropenyl-6-isopropyl-5-methoxypyrazine 5-Chloro-6-isopropenyl-3-isopropyl-l-methyl-2(177)-pyrazinone... [Pg.390]

A series of monoalkylpyrazines has been chlorinated specifically at the 3-position with sulfuryl chloride in the presence of iV,V-dimethylformamide the nucleus of 2,6-dialkylpyrazines is also readily chlorinated (687,693). The reaction of isobutyl-pyrazine with phosphoryl chloride and phosphorus pentachloride gave 2-chloro-5-isobutylpyrazine in 25% yield (693). 2-Acetonylpyrazine and 2-phenacylpyrazine with aqueous potassium hypochlorite gave 2-dichloromethylpyrazine (694). [Pg.80]

Chloro-2,5 diisobuty Ipyrazine 1 -oxide 2-(l -Acetoxy-2 -methylpropyl)-3- chloro-5-isobutylpyrazine 760a... [Pg.91]

Chloro-3,6-diisobutylpyrazine 1-oxide 5-(l -Acetoxy-2 -methyl)propyl-3-chloro-2-isobutylpyrazine 113b... [Pg.91]

Isobutylpyrazine with mixed phosphorus pentachloride-phosphoryl chloride at 95° gave 2-chloro-5-isobutylpyrazine (693). [Pg.102]

TS-Butyl-3-hydrazino-5-isobutylpyrazine 1-oxide was prepared from the chloro analogue and hydrazine hydrate at 130 (313) and 2-(l -acetoxy-2 -methylpropyl)-... [Pg.150]

Dichloro-3,6-dimethylpyrazine 1,4-dioxide with 0.5 sodium hydroxide at 20° for 5 hours gave 2-chloro-5-hydroxy-3,6-dimethylpyrazine 1,4-dioxide which resisted further alkaline hydrolysis (842) (possibly due to anion formation, whereas sodium ethoxide and sodium benzyloxide rapidly displaced both chloro substituents). Similarly bromoaspergillic acid (3-bromo-2-s-butyl-6-hydroxy-5-isobutylpyrazine... [Pg.151]

Methoxypyrazines (31) have been prepared by diazomethane methylation of 2-hydroxy-3-isobutylpyrazine (60, 311, 367), 2-hydroxy-3-isopropylpyrazine (59, 367), 2-hydroxy-3-propyl(ethyl or hexyl)pyrazine (367), 3-hydroxy-2-isobutyl-5(and 6)methylpyrazine and 2-hydroxy-3-isobutyl-5,6-dimethylpyrazine (368), 2,3-dihydroxypyrazine (832), 2-hydroxy-5-methoxy- and 2,5-dihydroxy-3,6-diphenyl-pyrazine (832), 2-hydroxy-6-methoxy(and benzyloxy)pyrazine (832), 2,6-dihydroxy-3,5-diphenylpyrazine (873), 2,3,5-trifluoro-6-hydroxypyrazine (851), 2-chloro-6-hydroxy-3,5-diphenylpyrazine (873), 2-chloro-6-hydroxy-5-methyl-3-phenylpyrazine (873), 2-chloro-6-hydroxy-3-methyl-5-phenylpyrazine (873), 5,6-dichloro-1 -cyclohexyl-34iydroxy-2-oxo-l, 2-dihydropyrazine (853), 2-chloro-5-hydroxy-3-methoxy-6-methoxycarbonylpyrazine (881), 2-(4 -amino-3, 5 -dibromo-phenylsulfonamido)-3Tiydroxy-6-methoxypyrazine (881), 2-amino-3-hydroxy-... [Pg.168]

Benzyloxy-3-hydroxymethyl-6-isobutyl-2-pyrazinamine 1-oxide (57, R = CH2OH) gave 2-benzyloxy-5-chloro-6-hydroxymethyl-3-isobutylpyrazine 4-oxide (58, R = ( 111 )11) (Bu CHjONO, CuCl—CuCli, N2, MeCN, 20°C, 30 min 75%) " and methyl 3-amino-6-benzyloxy-5-isobutyl-2-pyrazinecar-boxylate 4-oxide (57, R = CO2Me) gave methyl 6-benzyloxy-3-chloro-5-isobutyl-2-pyrazinecarboxylate 4-oxide (58, R = CO2Me) (likewise but 90 min 61%) ... [Pg.147]

Chloro-3-isobutylpyrazine 4-oxide gave 3-isobutyl-2(l//)-pyrazinone 4-oxide (111, R = Bu ) (5 M NaOH, reflux, 2 h 39%) 2-chloro-3-phenylpyrazine... [Pg.158]

Benzyloxy-5-chloro-6-hydroxymethyl-3-isobutylpyrazine 4-oxide gave 2-benzyloxy-5-chloro-3-isobutyl-6-[(tetrahydropyran-2-yloxy)methyl]pyrazine... [Pg.214]

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