4-benzyl-3,5-dioxo-2-methyl

Tellurinane 4-Benzyl-3,5-dioxo-2-methyl- E12b, 429 (R2TeCl2-Red.)... 

Purine, 1,6-dihydro-8,9-dimethyl-6-thioxo-synthesis, 5, 583 Purine, 2,6-dimethoxy-synthesis, 5, 596 Purine, 2,6-dimethoxy-7-methyl-rearrangement, 5, 558 Purine, 2,7-dimethyl-halogenation, 5, 547 Purine, 7,9-dimethyl-UV spectra, 5, 517 Purine, 8,8-dimethyl-synthesis, 5, 580 Purine, 6-dimethylamino-mass spectra, 5, 519 occurrence, 5, 600 Purine, 6-dimethylamino-9-benzyl-alkylation, 5, 531 Purine, 3,7-dimethyl-6,8-dioxo-methylation, 5, 534 Purine, 6,8-dioxo-alkylation, 5, 534... 

An jV-benzyl group, inserted for protection, has usually been removed by stirring in liquid ammonia while sodium chips were added until a blue color persisted. Thus 9-benzyl-l,6-dihydro-6-imino-l-methyl-8-azapurine furnished l,6-dihydro-6-imino-l-methyl-8-azapurine, and 9-benzyl-6-butylamino-8-azapurine gave 6-butylamino-8-azapurine in 75% yield. Hydrogenation over palladium was used to debenzylate 9-benzyl-7-methyl-2,6-dioxo-8-azapurinium betaine (similar to 18) at 45 C. 9-Benzyl-l-methyl-8-azapurin-6-one resisted all of these conditions, but hydrogenation over palladium in butanol-acetic acid at 117°C provided a 72% yield of 1 -methyl-8-azapurin-6-one. ... 

The potassium salt of 7-methyl-3-phenyl-2,4-dioxo-l,2,3,4-tetrahydropyrido[2,3- pyrimidine-5-carboxylate 153 was condensed with l-bromo-3-chloropropane or 1,4-dibromobutane in anhydrous DMF at room temperature to afford the A-l-alkyl derivatives 154 and 155, respectively <1994FA499>. The corresponding A-l-piperazinylalkyl derivatives of 153 were also prepared in more than 40% yield. Debenzylation of 6-benzyl-3-methylpyrido[4,3-,7 pyrimidine 156 by Pd/C-catalyzed hydrogenolysis in AcOH gave the analogue 157 <1994JHC1569>. 

Zi)-/V-Benzyl-/V- (1/ )-2-(ferf-butyldimethylsiloxy)-l-[(4V)-3,7-dioxo-1,2-diazepan-4-yl]ethyl)-2- [1-(phenylsulfonyl)-1/7-indol-3-yl]methyl)hexa-3,5-dienainide (63) lm ... 

Nitronsaure 2-(l-Oxo-2-indanyli-den)-ethan- -methylester E 4b. 893 (R2CH-N02 + CH2N2) 2H-l,3-Oxazin 3-Benzyl-2,4-dioxo-6-methyl-3,4-dihydro- E4, 246 (Cl-CO-NCO H- R-CH2-CO-R)... 

In a formal sense, alkyl ester type carboxy protecting groups, e.g. benzyl, allyl, 4-picolyl, and (9,10-dioxo-2-anthryl)methyl esters, can be viewed at as modified methyl esters. However, because of their specific properties and cleavage conditions these esters will be discussed separately. In this section a series of acetal, phthalimidomethyl, various phenacyl, acetonyl, 9-anthryhnethyl, and cyclopropyhnethyl esters will be presented. 

The following alkoxypyrazines have been prepared from the corresponding dichloropyrazines and alkoxide ions 2,3-dimethoxy-5,6-dimethyl(and diphenyl) (797) 2,3-dibenzyloxy (sodium benzyl oxide in benzyl alcohol at reflux for 24 hours (883)] [but 23-dichloropyrazine with sodium hydride and benzyl alcohol in xylene gave l,4-dibenzyl-2,3-dioxo-l,2,3,4-tetrahydropyrazine)(988)] 2-chloro-5-methoxy (838) 2,5-diethoxy-3,6-dimethyl (872) 2methanolic sodium methoxide refluxed for 2 h) 2,5-dimethoxy-3-phenyl (817) 2-chloro-5-methoxy(and ethoxy)-3,6-diphenyl (817) 2,5-dimethoxy-3,6-dimethyl (and diisopropyl) (844) 2,5-dimethoxy-3-isopropyl-6-methyl (methanolic potassium methoxide at reflux for 6 days) (844) 2(5)-s-butyl-3-chloro-6-ethoxy-5(2)-isobutyl (93) 2-chloro-6-methoxy (838, 883) 2,6-dimethoxy (reflux for 8h) (832) 2,6-diethoxy (reflux for 14 h) (883) 2-benzyloxy-6-chloro (1 equiv. of sodium hydride and benzyl alcohol in benzene at reflux) (832) 2,6-dibenzyloxy (5 equiv. of sodium benzyloxide in benzene at reflux gave 70%) (832) and 3,5-dimethoxy-2-methyl (535). 

Propyl-4-N-hmzyl-6-(l-methYl)ethYl-2,5-dioxo-l,4-nwrpholine To a slurry of resin 96 (R = propyl, R = benzyl 1.50 g, -0.75 mmol), prepared as described in the previous section, in THF (15 mb) were added (-i-)-2-bromo-3-methylbutyric acid (1.36 g, 7.5 mmol, 10 equiv.) and DIEA (2.6 mb, 15 mmol, 20 equiv.). PyBrOP (3.5 g, 7.5 mmol, 10 equiv.) was then added in one portion, and the reaction mixture was agitated at 50 °C until a ninhydrin test confirmed complete acylation (-18 h). The resin was then filtered off and washed with DMF (2x10 mb) and CH2CI2 (2x10 mb). The resin 99 was treated with a solution of 95 % TFA/5 % H2O for 1 h. After filtration, the TFA filtrate was concentrated to afford the desired (crude) product 100 as an oil. 

Benzyl-2 4,5,6-tetrahydro- 408 2- (Ethoxycarbonyl-methyl)-2,4,5,6-tetrahydro- 408 3- Hydroxy-2-phcnyl-2,4,5,6-tctrahydro- 440 3-Methyl-3,4.5,6-tetrahydro- 493 2- Phcnyl-2,4,5,6-tetrahydro- 408 3- PhenyI-3,4,5,6-tetrahydro- 493 4.6- Dit>xo-2-( 2-furyl)-4,6-dihydro- 319 4.6- Dioxo-2-phenyl-4,6-dihydro- 319 4.6- Dioxo-2-(2-thienyl)-4,6-dihydro- 319... 

Dioxo-3-ethyl-l, 5,6,7-tetrahydro- 677 Pyrazolo[3,4-d]-l, 3-oxazin l,3-Dimethyl-4-oxo-6-(2-oxo-propyl)-dihydro- 557 1- Acyl-3-methylthio-6-oxo-l,6-dihydro- 676 2- Benzyl-6-(4-nitro-phenyl)-4-oxo-2,4-dihydro-676 4-Amino-7-chlor-phenyl- 976 2-(4-Aminosulfonyl-phenyl)-4,7-dichIor- 977 2-(4-Aminosulfonyl-phcnyl)-4,7-dihydroxy- 922 4-Anilino-7-chlor-2-(3-thienyl)- aus 4,7-DichIor-2-(3-thicnyI)- pyriclazino-[4,5-d]-l,3-thia7.ol)/Ethanol 976 7-Chlor-4-ethoxy-2-methyl- 972 7-Chlor-4-methoxy-2-phenyl- 972 7-ChIor-4-(3-pyrroIidino-propyloxy)-2-(2-thienyI)- 972... 

Poly(y-benzyl-i.-glutamate) macromonomers were synthesized starting with the polymerization of benzyl (S)-3-(2,5-dioxo-l,3-oxazolidin-4-yl) propionate (or y-benzyl-L- glutamate-N-carboxyanhydride [189]) with the primary amino group of the N-methyl-N-(4-vinylphenethyl) ethylene diamine (1) [190] (Scheme 58). 

Dimethylamino)-1-(4-(4-morpholinyl) phenyl)-2-(phenylmethyl)-1-butanone. See 2-Benzyl-2-(dimethylamino)-4 -morpholinobutyrophenone 4-(Dimethylamino) nitrosobenzene p-(Dimethylamino) nitrosobenzene. See N,N-Dimethyl-p-nitrosoaniline 4-(Dimethylamino)-1,4,4a,5,5a,6,11,12a-octahydro-3,5,6,10,12,12a-hexahydroxy-6-methyl-1,11-dioxo-2-naphthacenecarboxamide monohydrochloride. See Oxytetracycline hydrochloride... 

Dioxo-2 iinino-3 [a iminO 4>methyl< benzyl]-tetrahyc furan 17 II 536. 

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