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Pyrrole-2,5-diones

Furo[2,3-amino-synthesis, 4, 986 Furo[3,4-d]pyrimidinedione synthesis, 4, 987 Furopyrimidines, 4, 986 Furo[2,3-d]pyrimidines synthesis, 4, 986 Furo[3,2-d]pyrimidines synthesis, 4, 987 Furo[3,2- 6]pyrone synthesis, 4, 994 Furo[3,2-c]pyrone synthesis, 4, 993 Furo[3,2-6]pyrrole, hexahydro-biological activity, 6, 1024 1 H-Furo[3,4-6]pyrrole-2,3-dione, 4,6a-diphenyl-6-(phenylimino)-6,6a-dihydro-synthesis, 6, 1004 Furopyrroles... [Pg.638]

Other PK variations include microwave conditions, solid-phase synthesis, and the fixation of atmospheric nitrogen as the nitrogen source (27—>28). Hexamethyldisilazane (HMDS) is also an excellent ammonia equivalent in the PK synthesis. For example, 2,5-hexanedione and HMDS on alumina gives 2,5-dimethylpyrrole in 81% yield at room temperature. Ammonium formate can be used as a nitrogen source in the PK synthesis of pyrroles from l,4-diaryl-2-butene-l,4-diones under Pd-catalyzed transfer hydrogenation conditions. [Pg.82]

Hydroxy group of 8-hyd oxy-2-cycloalkyl-2,3,4,6,ll,lla-hexahydro-l//-pyrazino[l,2-i]isoquinoline-l,4-diones was alkylated with allyl bromide, 2-(bromodifluoromethyl)pyridines, l-(bromodifluoromethyl)- and l-(bro-momethyl)benzenes, halomethyl derivatives of different heterocycles (pyridine, pyrazine, pyrazole, pyrrole, thiazole, thiophene) in the presence of CS2CO3 or K2CO3 (98MIP7). Hydroxy group of 8-hydroxy-2-cyclopentyl-... [Pg.313]

A small amount of this mixture can also be obtained when the isomeric 3-oxatetracy-clo[3.1.1.02,4.06,7]heptene is heated to 145°C. The major product, however, is 2-oxabi-cyclo[3.2.0]hepta-3,6-diene.113 2,3,5,6,9-Pentamethyl-4-oxa-9-azatetracyclo[5.3.0.02,6.03 5]dec-l(7)-ene-8,10-dione readily isomerizes to the corresponding oxepino[4,5-c]pyrrole. 14... [Pg.10]

Benzenediamine (538) and l-diphenylamino-3,4-dihydro-[l]benzothiopy-rano[4,3-/ ]pyrrole-2,3(l//)-dione (539) in dichloromethane (containing a trace of hydrogen chloride) at 20°C for 48 h furnished 3-(4-diphenylhydrazono-3,4-dihydro-2//-[l]benzothiopyran-3-yl)-2(l//)-quinoxalinone (540) in 30% yield. [Pg.73]

In the frame of a medicinal project at J J Pharmaceutical Research and Development aimed at designing new potent and selective glycogen synthase kinase-3/i (GSK-3/3) inhibitors, the C-3 derivatization of the 1-methyl-4-[l-alkyl-lff-indol-3-yl]-lff-pyrrole-2,5-dione scaffold was explored [31]. Microwave-assisted Stille reaction of 3-chloro-l-methyl-4-[l-alkyl-lff-indol-3-yl]-lH-pyrrole-2,5-diones with (2,4-dimethoxy-5-pyrimidinyl)(tributyl) stannane at 200 °C yielded in 6 min the desired 3,4-diaryl-lff-pyrrole-2,5-diones in moderate yields (Scheme 12). [Pg.162]

In 2007, a novel C2-symmetric diphenylthiophosphoramide ligand was found to be a fairly efficient chiral ligand for the Cu(I)-promoted 1,3-dipolar cycloaddition of imines and pyrrole-2,5-dione derivatives to give the corresponding adducts in moderate to good enantioselectivities and good yields (Scheme 10.14). ... [Pg.303]

Amino-7-chloro-2,3(l//,4//)-quinoxalinedione (116) and 2,5-dimethoxytetra-hydrofuran (117) gave 6-chloro-7-(pyrrol-l-yl)-2,3-(l//,4//)-quinoxaline-dione (118) (AcOH, reflux no further details).16... [Pg.278]

The wide latitude of structural variation consistent with bioactivity in this series is illustrated by the observation that antiinflammatory activity is maintained even when the second aromatic group is attached directly to the pyrrole nitrogen rather than to the heterocyclic ring via a carbonyl group as in the previous case. Condensation of p-chloroaniline with hexane-2,5-dione (or its dimethoxy-tetrahydrofuran equivalent) affords pyrrole 7. The acetic acid side chain is then elaborated as above. Thus, Mannich reaction leads to the dimethylaminomethyl derivative 8, which is in turn methylated (9) the quaternary nitrogen replaced by cyanide to afford 10. Hydrolysis of the nitrile then gives clopirac (11). [Pg.234]

Langer and coworkers constructed diverse O- and N-heterocydic scaffolds, such as y-alkylidene-a-hydroxybutenolides and pyrrolo[3,2-b]pyrrol-2,5-diones, exploiting the well-established cyclization strategy of bisnucleophiles with oxalic acid derivatives [163], while Stockman s research group reported in this context on a novel oxime formation/Michael addition providing the structural core of the alkaloid perhydrohistrionicotoxin [164]. [Pg.94]

Animal glue HMDS Pyrrole 2 carboxamide, diketodipyrrole, pyrrole[1,2 a]piperazine 3,6 dione 28... [Pg.307]

Furo[3,4-c]pyrrolediones are important intermediates in the synthesis of diketo-pyrrolopyrrole (DPP) pigments. Smith and coworkers have described the preparation of several different 3,6-diaryl-substituted furo[3,4-c]pyrrole-l,4-diones by microwave-assisted cyclization of readily available 4-aroyl-4,5-dihydro-5-oxo-2-arylpyrrole-3-carboxylates (Scheme 6.192) [353]. While conventional heating in Dowtherm A at 230-240 °C for 64 h provided only moderate product yields, microwave irradiation of the neat starting material at 250 °C for 10 min provided significantly increased yields. [Pg.230]

Alternatively, Ballini devised a new strategy to synthesize tri-alkylated pyrroles from 2,5-dialkylfurans and nitroalkanes <00SL391>. This method involves initial oxidation of 2,5-dimethylfuran with magnesium monoperoxyphthalate to cA-3-hexen-2,5-dione (6). Conjugate addition of the nitronate anion derived from the nitro compound 7 to 6 followed by chemoselective hydrogenation of the C-C double bond of the resulting enones 8 (obtained by elimination of nitrous acid from the Michael adduct) completes the conversion to the alkylated y-diketones 9. Final cyclization to pyrroles 10 featured improved Paal-Knorr reaction conditions involving reaction of the diketones with primary amines in a bed of basic alumina in the absence of solvent. [Pg.112]

Reaction of the thia-amino acid 392 with trifluoroacetic anhydride gave the 2,2,2-trifluoro-l-[7-(trifluoromethyl)-l//-pyrrolo[l,2-c]-[l,3]thiazol-6-yl] ethanone pyrrole 395. The formation of the pyrrole can be rationalized by a sequence involving trifluoroacetylation of the enamine 392 affording dione 393 followed by loss of water and carbon dioxide to give the aromatic product 395. These decarboxylations afford fluorinated derivatives of heterocyclic skeletons known to exhibit interesting biological activity (Scheme 58) <2000T7267>. [Pg.96]

The preparation of five-membered rings in solid-phase organic chemistry has been reported in several publications. Versatile syntheses of these heterocycles with different numbers and kinds of heteroatoms have been described. The synthesis of five-membered rings containing one nitrogen atom (Fig. 3.6) as pyrrolidines (231) [311-316] pyrroles (232) [317-320] pyrrolidinones (233) [321-323] pyr-rolinones (234) [324—326] 2,5-pyrrolidinediones (235) [327-329] 2,4-pyrrolidine-diones (236) [330-332] 2,5-pyrrolinediones (237) [333] or heterocycles with one oxygen or one sulfur atom like tetrahydrofurans (238) [334—336] 2,5-dihydrofurans (239) [337], furans (240) [338, 339], yS-lactones (241) [340-343], 2,5-dihydrofura-nones (242) [344] (Scheme 3.35) and thiophenes (243) [345, 346] can be accomplished on solid supports. [Pg.179]

N-Protected AAs were activated in situ with isopropenyl chloroformate to give an intermediate anhydride which reacted with Meldrum s acid in the presence of 4-dimethylaminopyridine (DMAP) to give the corresponding l,3-dioxane-4,6-dione. The reaction conditions are very stringent. Further transformation upon heating in an organic solvent yielded the pyrrole derivative (Scheme 15) [87JCS(P1)1177]. [Pg.14]

The syntheses shown in Scheme 26 (71CB1573) are based on dibenzo-/3-tropolone (108) and its enamines. Condensation of 108 and benzoin in the presence of ammonia affords pyrrole 109. The morpholino enamine gives pyrazole 110 via benzoylation, hydrolytic elimination of morpholine, and cyclization, whereas diazo-group transfer onto the anilino enamine leads to triazole 111. Dione 108 and p-nitrophenylazide in one step give predominantly the p-nitro derivative of 111 (92G249). [Pg.107]

Regioselective synthesis of 2-substituted pyrroles using oximinocyanoacetate esters or related compounds in a Knorr-type reductive condensation with diketones was described . Thus, oximinocyanoacetates 63 reacted with pentane-2,4-diones 64 in hot... [Pg.242]

Keywords Acetylacetates, 2-Amino-2-deoxyaldoses, Barbituric acids, C-Glyco-sides, Dimedone, Furans, Garcia-Gonzalez reaction, Green chemistry, Hexoses, Meldrum s acid, Penta-2,4-dione, Pentoses, Pyrroles, Reactions in water, Tetrahy-drofuranylfurans... [Pg.1]

The Knovenagel condensation under basic conditions was first investigated with D-glucosamine chlorhydrate (28.HC1) as the sugar. The condensation of this reducing amino sugar with pentane-2,4-dione 1 in aqueous acetone in the presence of sodium carbonate afforded the pyrrole derivative 29 in 85% yield [99] (Scheme 5). The reaction was extended to other 2-amino-2-deoxy-aldose and carbon nucleophiles [100-104]. [Pg.6]


See other pages where Pyrrole-2,5-diones is mentioned: [Pg.34]    [Pg.129]    [Pg.796]    [Pg.815]    [Pg.816]    [Pg.817]    [Pg.871]    [Pg.280]    [Pg.83]    [Pg.144]    [Pg.692]    [Pg.970]    [Pg.123]    [Pg.8]    [Pg.1036]    [Pg.133]    [Pg.62]    [Pg.180]    [Pg.191]    [Pg.6]    [Pg.41]    [Pg.47]   


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1- pyrrole-2,3-dione

1- pyrrole-2,3-dione

1-ethyl-1//-pyrrole-2,5-dione

Pyrrole-2,5-dione amine

Thieno pyrrole-4,6-dione

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