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Phthalazine, hydroxy

When large groups, such as phenyl, bromo, ethoxycarbonyl or nitro are attached at position 3, the principal products are l-alkylcinnolin-4(l/f)-ones. Cyanoethylation and acetylation of cinnolin-4(l/f)-one takes place exclusively at N-1. Phthalazin-l(2/f)-ones give 2-substituted derivatives on alkylation and acylation. Alkylation of 4-hydroxyphthala2in-l(2/f)-one with an equimolar amount of primary halide in the presence of a base leads to 2-alkyl-4-hydroxyphthalazin-l(2/f)-one and further alkylation results in the formation of 4-alkoxy-2-alkylphthalazinone. Methylation of 4-hydroxy-2-methyl-phthalazinone with dimethyl sulfate in aqueous alkali gives a mixture of 4-methoxy-2-methylphthalazin-l(2/f)-one and 2,3-dimethylphthalazine-l,4(2//,3//)-dione, whereas methylation of 4-methoxyphthalazin-l(2/f)-one under similar conditions affords only 4-methoxy-2-methylphthalazinone. [Pg.17]

Phthalazin-1 (2H)-one, 4-hydroxy-2-methyl-methylation, 3, 17 Phthalazin-l(2H)-one, 4-methoxy-methylation, 3, 17 Phthalazinones in thermography, 1, 392 Phthalazin-l(2H)-ones alkylation, 3, 17 reaction... [Pg.745]

Although early investigators considered that 4-hydroxy-l-methyl-phthalazine existed as such in neutral solution, they refer to basicity data which, in the light of present knowledge, would lead to assignment of the l-methylphthalazin-4-one structure (84, R = Me) to the predominant tautomer. The correctness of the oxo structure for phthal-azin-l-one (84, R — H) has been demonstrated using infrared spectroscopy. ... [Pg.366]

The silylation-amination of 5,10-dihydroxy-l,4-dioxo-l,2,3,4-tetrahydroben-zo[g]phthalazine 281 for 27 h at 170 °C with excess N(2-aminoethyl)piperidine 282 and HMDS 2 proceeds with catalytic amounts of Ts0H-H20 to afford, via the activated persilylated intermediate in which the sensitive phenolic hydroxy groups are protected, the 1,4-bis-amine 283 in 67% yield. All conventional efforts with POCI3, PCI5, or SOCI2 to convert 281 into the corresponding 1,4-dichloro compound, to be followed by amination, resulted in failure [86] (Scheme 4.35). [Pg.64]

The hydroxy group of l-[3-hydroxyazetidin-l-yl)carbonyl]-3-phenyl-4-oxo-4//-pyrido[2,l-a]phthalazine (85) was O-methylated with methyl iodide in DMF in the presence of potassium carbonate (87EUP226196). [Pg.107]

Aryl halides bearing strong electron-withdrawing groups and thus allowing nucleophilic aromatic substitution can be used for the arylation of azinone anions. 4-(4-Hydroxy-3-methylphenyl)phthalazin-l(2//)-one has been arylated simultaneously at N-2 and at the phenolic OH with 4-chlorobenzonitrile and potassium carbonate in dimethyl-acetamide (DMA) <2005CHJ200>. [Pg.26]

The strategy is impressively simple the phthalazine derivative 15 can readily be prepared from quinine in one step. Being a divinyl derivative, it can be submitted as a cross-linking unit in the radical polymerization of methyl methacrylate (MMA) or 2-hydroxy methacrylate (HEMA). Thereby, an immobilized (DHQ-PHAL) derivative 16 is obtained, which is suited for the asymmetric dihydroxylation of frantr-stilbene (>99 % ee) and ( )-cinnamic acid methyl ester (>99 % ee. Table 1). The insoluble catalyst can be recovered by simple filtration, and its repeated... [Pg.333]

Disposition in the Body. Readily absorbed after oral administration. It undergoes first-pass acetylation, the extent of which is genetically determined bioavailability 30 to 35% in slow acetylators, 10 to 16% in rapid acetylators. The major metabolites are 3-methyl-l,2,4-triazolo[3,4-a]phthalazine (MTP—the acetylation product) hydralazine pyruvic acid hydrazone (HPH) which is the major plasma metabolite 4-(2-acetylhydra-zino)phthalazin-l-one (A-AcHPZ) which is the major urinary metabolite 3-hydroxymethyl-1,2,4-triazolo[3,4-a]phthalazine (3-OHMTP). About 65% of a dose is excreted in the urine in 24 hours. In rapid acetylators, about 30% is excreted as A-AcHPZ and 10 to 30% as conjugated 3-OHMTP in slow acetylators, about 15 to 20% is excreted as A-AcHPZ and up to 10% as conjugated 3-OHMTP. Other metabolites include phthalazin-1-one (PZ), 1,2,4-triazolo[3,4-fl]phthalazine (TP), 9-hydroxy-MTP, phthalazine, tetrazolo[5,l-a]phthalazine, and hydrazones of hydralazine formed with acetone and a-ketoglutaric acid. About 10% of a dose is eliminated in the faeces. [Pg.662]

Phthalazine 4-(4-Amino-3-methyl-phenyl)-l-hydroxy- E9a, 751 (2-Arocyl-benzoesaure/N2H4)... [Pg.85]

Cinnoline 3-Bromo-4-hydroxy-6-nitro- E9a, 714 (H - Br) Phthalazine 4-Bromo-l-hydroxy-7-nitro- E9a, 757 f. (3-Br - 6-N02 -1 -oxo — 1,3-H2 — 2-benzofuran/ N2H4)... [Pg.438]

Phthalazine 4-Amino-l-hydroxy-E9a, 753 (2-CN-l-COOR-benzene/N2H4), 758 (Thio-phthalimid + N2H4) Pyrido 2,3-b pyrazin... [Pg.464]

Phthalazine 4-Hydrazino-l-hydroxy-E9a, 759 (Phthalimid-l-imid/ N2H4) E16a, 719f. [Pg.474]

Phthalazine 4-Hydroxy-l-methyl-E9a, 751 (2-Acetyl-benzoesaure/ N2H4), 756 (l,2-H2-Der./Oxid.) Phthalazinium-l-olate 3-Methyl-E9a, 785 (OT -+ O or N-Methylamino-phthalimid/ NaBH4)... [Pg.590]

Phthalazine l,4-Dihydroxy-5(or 6)-dimethylamino- E9a, 752 (subst. Phthalanhydrid/N2H4) lH-PyrazoI 5-Methyl-5-nitro-4-phenyl-4,5-dihydro- X/l, 426 Pyrido[2,3-d]pyrimidin 4-Hydroxy-2-oxo-l-propyl-1,2-dihydro- E9c,... [Pg.745]

Phthalazine 4-(l-Carboxy-ethylami-no)-l-hydroxy- E9a. 759 2-CHj - 3,6-(OH)2 - + NaOH ... [Pg.868]

Phthalazine 6-Chloro-4-(ethoxycar-bonyl-methyl)-l-hydroxy- E9a, 760 [3-(COOR — methylen) —... [Pg.984]


See other pages where Phthalazine, hydroxy is mentioned: [Pg.744]    [Pg.63]    [Pg.379]    [Pg.235]    [Pg.23]    [Pg.37]    [Pg.73]    [Pg.80]    [Pg.90]    [Pg.93]    [Pg.72]    [Pg.744]    [Pg.745]    [Pg.310]    [Pg.72]    [Pg.437]    [Pg.438]    [Pg.439]    [Pg.445]    [Pg.454]    [Pg.590]    [Pg.721]    [Pg.844]    [Pg.894]   
See also in sourсe #XX -- [ Pg.384 ]




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