2.4- dioxo-4-phenyl

Two main synthetic approaches were used for the preparation of amines (2). A first approach (scheme 2) considered 2,4-dioxo-5-phenyl-2,3,4,5-tetrahydro-lH-l,5-benzodiazepine (5), obtained from phenylenedyamine (4) [17], as a common intermediate... 

Dioxo-5-phenyl.oxazolid>n 27 1 322. Anhydio- N-( ykaloTl-anthranil8taie]... 

Amino-1,3-dimethyl-2,4-dioxo-5-phenyl-2,3,4,5-tetrahydro-1 H-pyrano[2,3-d]-pyrimidine-6-carbonitrile (18a)... 

Cumarin VI/lc, 60 Cyclopropan Dioxo-phenyl- E17d, 2993 (Ar — Cl3-cyclopro-pen +H20)... 

Piperidine, 3-aryIoxymethyI-4-phenyI-as antidepressant, 1, 169 Piperidine, JV-bromo-photoelectron spectroscopy, 2, 142 Piperidine, cis-4- t-butyl-r- cyclohexyl-1 -phenyl-X-ray analysis, 2, 161 Piperidine, 3-chloro-pyrrolidines from, 4, 147 Piperidine, N-chloro-photoelectron spectroscopy, 2, 142 reactions, 2, 373 trimerization, 3, 510 Piperidine, 4-cycIopentyI-2,6-dioxo-synthesis... 

Purines, N-alkyl-N-phenyl-synthesis, 5, 576 Purines, alkylthio-hydrolysis, 5, 560 Mannich reaction, 5, 536 Michael addition reactions, 5, 536 Purines, S-alkylthio-hydrolysis, 5, 560 Purines, amino-alkylation, 5, 530, 551 IR spectra, 5, 518 reactions, 5, 551-553 with diazonium ions, 5, 538 reduction, 5, 541 UV spectra, 5, 517 Purines, N-amino-synthesis, 5, 595 Purines, aminohydroxy-hydrogenation, 5, 555 reactions, 5, 555 Purines, aminooxo-reactions, 5, 557 thiation, 5, 557 Purines, bromo-synthesis, 5, 557 Purines, chloro-synthesis, 5, 573 Purines, cyano-reactions, 5, 550 Purines, dialkoxy-rearrangement, 5, 558 Purines, diazoreactions, 5, 96 Purines, dioxo-alkylation, 5, 532 Purines, N-glycosyl-, 5, 536 Purines, halo-N-alkylation, 5, 529 hydrogenolysis, 5, 562 reactions, 5, 561-562, 564 with alkoxides, 5, 563 synthesis, 5, 556 Purines, hydrazino-reactions, 5, 553 Purines, hydroxyamino-reactions, 5, 556 Purines, 8-lithiotrimethylsilyl-nucleosides alkylation, 5, 537 Purines, N-methyl-magnetic circular dichroism, 5, 523 Purines, methylthio-bromination, 5, 559 Purines, nitro-reactions, 5, 550, 551 Purines, oxo-alkylation, 5, 532 amination, 5, 557 dipole moments, 5, 522 H NMR, 5, 512 pJfa, 5, 524 reactions, 5, 556-557 with diazonium ions, 5, 538 reduction, 5, 541 thiation, 5, 557 Purines, oxohydro-IR spectra, 5, 518 Purines, selenoxo-synthesis, 5, 597 Purines, thio-acylation, 5, 559 alkylation, 5, 559 Purines, thioxo-acetylation, 5, 559... 

Pyridazine, 4-diazo-5,6-dioxo-1 -phenyl-1,4,5,6-tetrahydro-rearrangement, 3, 10 Pyridazine, 4,5-di-S-butyl-perfluoro... 

This derivative is prepared from an A-protected amino acid and the anthrylmethyl alcohol in the presence of DCC/hydroxybenzotriazole. It can also be prepared from 2-(bromomethyl)-9,10-anthraquinone (Cs2C03). It is stable to moderately acidic conditions (e.g., CF3COOH, 20°, 1 h HBr/HOAc, / 2 = 65 h HCl/ CH2CI2, 20°, 1 h). Cleavage is effected by reduction of the quinone to the hy-droquinone i in the latter, electron release from the —OH group of the hydroqui-none results in facile cleavage of the methylene-carboxylate bond. The related 2-phenyl-2-(9,10-dioxo)anthrylmethyl ester has also been prepared, but is cleaved by electrolysis (—0.9 V, DMF, 0.1 M LiC104, 80% yield). ... 

The related 2-phenyl-2-(9,10-dioxo)anthrylmethyl ester has also been prepared, but is cleaved by electrolysis (—0.9 V, DMF, 0.1 MLiC104, 80% yield). ... 

Dipolar eycloaddition reaction of thioisomiinchnones 208 with dimethyl aeetylenediearboxylate (DMAD) furnished adduets 209, whieh underwent a sulfur extrusion to give 2-substituted-7-phenyl-l,8-dioxo-l//,8//-pyrido[l,2-c]pyrimidine-5,6-dicarboxylates 210 (OOOL581). 

Chemical Name (+)-1 -Benzyl-4-[(2,6-dioxo-3-phenyl)-3-piperidyl] piperidine Common Name Dexbenzetimide dextrobenzetimide benzetimide Structural Formula ... 

After 6 hours the calculated amount of hydrogen has been taken up. The residue obtained after filtering and evaporating is taken up in benzene and extracted twice with diluted sodium carbonate solution. The alkali extract is then made acid to Congo red with 6N hydrochloric acid and the precipitate is taken up in ethyl acetate. The solution obtained is washed twice with salt solution, dried with sodium sulfate and evaporated. The residue is recrystallized from ether/petroleum ether. 1-(p-hydroxyphenyl)-2-phenyl-4-n-butyl-3,5-dioxo-pyrazolidine melts at 124° to 125°C. 

Oxo-4-propyl-4-phenyl-imidazolidin Zu 11,4 g (0,3 Mol) Lithiumalanatin 600ml abs. Ather gibt man unter Riihren 21,8 g (0,1 Mol) 2,4-Dioxo-5-propyI-5-phenyI-imidazoIidin. Die Mischung wird 30 Stdn. unter RiickfluB erhitzt, danach mit 44 ml Wasser und 11m/ 15%-iger Natriumhydroxid-Losung hydrolysiert und fil-triert. Man kocht den Niederschlag mit Athanol aus, filtriert, dampft die Solventien ab und kristallisiert das Roh-produkt aus verd. Athanol urn Ausbeute 8,9 g (480/0 d.Th.) F 207-209°. 

Dioxo-3-alkyl-imidazolidine werden mit Lithiumalanat in der Hitze zu 3-A1-kyl-imidazolidinen reduziert z.B. 2,4-Dioxo-3-methyl-5-phenyl-imidazolidin zu 7-Methyl-4-phenyl-imidazolidin (43% d.Th.) bei 23° und inverser Zugabe wird dagegen (vgl. S. 252) 2-Hydroxy-l-methyl-4-phenyl-imidazol (66% d. Th.) erhalten, das sich unter energischen Bedingungen zum 7-Methyl-4-phenyl-imidazol (25 % d. Th.) reduzieren laftt3 ... 

Athyl-5-phenyl-barbitursaure liefert durch Reduktion mit einem kleinen OberschuB an Natriumboranat/Bortrifluorid 2,4-Dioxo-5-dthyl-5-phenyl-hexahydro-pyrimidin. Zum Gelingen der Reaktion muB der reduzierte Ansatz mit alkalischem Wasserstoffper-oxid oxidiert werden (s.S. 58, 81). Die Reduktion gelingtmeist nur bei 5-Phenyl-barbitur-sauren3. 

Dioxo-4,8-diphenyl-l,3,5,7-tetraaza-bicyclof3.3.0]octan laBt sich durch Lithium-alanat in5-Hydroxy-3- phenyl-1,2,4- triazolidin (14% d.Th.), N-Methyl- benzylamin auf-spalten4 ... 

In AcetonitrilundTctraathylammoniumperchlorat als Leitsalz erhalt manbei —2 V an Quecksilber aus l,5-Dioxo-l,5-diphenyl-pentan 1,2-Dihydroxy-1,2-diphenyl-cyclopen-tan (76% d.Th.)2, vgI"3 und aus l,6-Dioxo-l,6-bis-[4-hydroxy-phenyl]-hexan /,2-Dihydroxy- 1,2-bis- 4-hydroxy-phenyl]-cyclohexan3 ... 

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