5.6.7.8- Tetrahydro-1 -phthalazinone

Ethyl-2-thenoyl)-3,4,5,6-tetrahydrobenzoic acid (69) gave 4-(5-ethylthien-2-yl)-5,6,7,8-tetrahydro-l(2fl)-phthalazinone (70) (H2NNH2 H2O, EtOH,... 

Methyl-5-phenylsulfonyl-3(2iJ)-pyridazinone (152, R = SOaPh) underwent Diels-Alder addition by 2,3-dimethyl-l,3-butadiene (151) to give 2,6,7-trimethyl-4a-phenylsulfonyl-4a,5,8,8a-tetrahydro-1 (2fl)-phthalazinone (153, R = S02Ph) (reactants, PhH, reflux, 10 days 90%) methyl l-methyl-6-oxo-l,6-dihydro-4-pyridazinecarboxylate (152, R = C02Me) likewise gave methyl 2,6,7-trimethyl-1 -oxo-1,2,4a,5,8,8a-hexahydro-4a-phthalazinecarbox-ylate (153, R = C02Me) (70%) such additions by an unsymmetric diene... 

Bromobutyl)-4-(3,4-dimethoxyphenyl)-4a,5,8,8a-tetrahydro-l(2//)-phthala-zine with 6-p>-hydroxyphenyl-5-methyl-5,6-dihydro-3(2//)-pyridazinone gave 4-(3,4-dunethoxyphenyl)-2- 4-[p-(4-methyl-6-oxo-l,4,5,6-tetrahydropyridaz-in-3-yl)phenoxy]butyl -4a,5,8,8a-tetrahydro-l(2H)-phthalazinone (106) (reactants, K2CO3, trace KI, Me2NCHO, 60°C, >3 h 35%) analogs likewise. o... 

The ionization constants for several 5- or 6-substituted l,4(2//,37/)-phthalazi-nediones (10) have been measured for comparison with those of the unsubstituted molecule (10, R = H) ° the and NMR spectra for some 4-substituted l(27/)-phthalazinones (11) have been reported the predominant conformation of 4-phenyl-5,6,7,8-tetrahydro-l(27/)"Phthalazinone (12) has been determined by and NMR the MS fragmentahon patterns of simple 4-(co-hydroxyalkyl-amino)-l(27/)-phthalazinones (13) have been studied 4-benzoyloxy-l(27/)-phthalazinone (14) has been found to catalyze trimethylsilylation of otherwise resistant substrates by hexamethyldisilazane and a series of substituted 1,4(2//,37f)-phthalazinediones (15) include some with potent hypolipidemic achv-... 

Dimethoxyphenyl)-l(2H)-phthalazinone (49, R = H) gave 2-benzyl-4-(3,4-dimethoxyphenyl)-l(2H)-phthalazinone (49, R = CH2Ph) (substrate, NaH, MeaNCHO, 20°C, 3h then PhCHaCU, 20X, 4h 61%) analogs like 2-benzyl-4-(3,4-diniethoxyphenyl)-5,6,7,8-tetrahydro-l(2//)-phthalazinone (57%) were made likewise. 

Phenyl-4a,5,6,7,8,8a-hexahydro-l(2//)-phthalazinone (71) gave 4-phenyl-5,6,7,8-tetrahydro-l(277)-phthalazinone (72) (CUCI2, MeCN, reflux, Ih ... 

Cycloheptyl-4-(3-cyclopentyloxy-4-methoxyphenyl)- (116, R = OC5H9) underwent selective hydrolysis to 2-cycloheptyl-4-(3-hydroxy-4-methoxyphenyl)-4a,5,8,8a-tetrahydro-l(277)-phthalazinone (116, R = H) (TsOH- H2O, PhMe, reflux, 3h 71%). ... 

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