1.2.3.4- Tetrahydro-2,3-dioxo-4,4-dimethyl

Dioxo-l,3-dimethyl-tetrahydro-imidazol- (4-spiro-2) - 4,6,7-trimethyl-1,2,3.4-tetrahydro-chinoxalin ... 

Dioxo-2,3-dimethyl-1,2,3,4-tetrahydro-phthalazin wird in Acetat-Puffer im we-sentlichen zuml-Oxo-2,3-dimethyl-l,2,3,4-tetrahydro-phthalazin (80% d.Th.) reduziert, in 4n Salzsaure wird dagegen unter Methylamin-Abspaltung 1 -Oxo-2-methyl-2,3-dihy-dro-isoindol (46% d.Th.) erhalten1 (vgl. a. S. 595f.) ... 

CN 1,2,3,6-tetrahydro-1,3-dimethyl-2,6-dioxo-7//-purine-7-acetic acid... 

RN 18833-13-1 MF C H,oN404 XC4H10N2 MW unspecified EINECS 242-614-3 CN l,2,3,6-tetrahydro-l,3-dimethyl-2,6-dioxo-7//-purine-7-acetic acid compd. with piperazine... 

Gompper and co-workers also showed that refluxing of dimethyl 3,4-diaminothieno[2,3-6]thiophene-2,5-dicarboxylate (106, R = NHj, Z = COjMe) with fbrmamide or treatment of the 3,4-bisethoxymethyl-enamino derivative with ammonia led to 3,4,7,8-tetrahydro-4,7-dioxo-pyrimido[5,4-6 ]thieno[2,3-6]pyrimido[5,4- >]thiophene (251). [Eq. (89)]. 

In einer Photoreaktion reagiert 2,5-Diphenyl-l,3,4-oxadiazol mit l,3-Dimethyl-2,4-dioxo-1,2,3,4-tetrahydro-pyrimidin unter Ringspaltung. Das gebildete 5-(a.-Benzoylhydrazono-ben-zyl)-1,3-dimethyl-2.4-dioxo-1.2,3,4-teirahydro-pyrimidm (4 44%) kann zu anderen Folgepro-dukten wciterreagieren78". 

Disubstituierte 5-Brom-6-methyl-2,4-dioxo-l, 2,3,4-tetrahydro-pyrimidine rcagieren mit aliphatischen Aminen in Dimethylformamid unter Ersatz des Brom-Atoms durch eine Amino-Gruppe4. Dagegen erfolgt bei Reaktion mit aromatischen Aminen allylische Substitution durch eine Arylamino-Gruppe, und man erhalt z.B. 6-Anilino-1,3-dimethyl-... 

Dioxo-l,4,7,10-tetrahydro-l,10-phenanthroline (72) with dimethyl sulfate gives l,4-dihydro-7-methoxy-l-methyl-4-oxo- 1,10-phenanthroline (73) rather than a quaternary salt, steric hindrance presumably preventing alkylation of both nitrogens.203 A related alkylation has also been reported.295 1,2,3,4-Tetrahydro-1,10-phenanthrolines similarly form 1-alkyl derivatives rather than 10-alkyl quaternary salts with alkyl halides.38 The rate of methylation of 1,10-phenanthroline with methyl iodide in dimethyl sulfoxide has been studied,296 and the polaro-graphic reduction of 1 -methyl- 1,10-phenanthrolinium iodide was reported.286... 

Ueno et al. 15 reacted l,4-dioxo-l,2,3,4-tetrahydroisoquinoline (406) with carbon disulfide, then methylated to 407, which, with DMAD and potassium carbonate in DMF, gave dimethyl 6,11-dioxo-l-methylthio-3,4, 6,1 l-tetrahydro[l, 4]thiazino[4,3-6]isoquinoline-3,4-dicarboxylate (408). 

Reaction of (R)-phenylglycinol with dimethyl acetylenedicarboxylate in boiling MeOH 12 h, followed by the treatment of the reaction mixture with acryloyl chloride yielded l,6-dioxo-3,4,7,8-tetrahydro-lH,6H-pyrido [2,l-c][l,4]oxazine-carboxylate 470 (07LOC4). 

Ethyl 6,7-dimethyl-4-oxo-1,4-dihydro-1, 5-naphthyridine-3-carboxylate 1 -Ethyl-6,7-dimethyl-4-oxo-1,4-dihydro-1, 5-naphthyridine-3-carboxylic acid Ethyl 4,6-dioxo-1,4,5,6-tetrahydro-1, 5-naphthyridine-3-carboxylate Ethyl 4,8-dioxo-1,5,8-tetrahydro-1, 5-naphthyridine-3-carboxylate Ethyl 7-ethoxy-l-ethyl-4-oxo-l,... 

Amino-2,7-dimethyl-3,8-dioxo-6-phenyl- 2,3,7,8-tetrahydro-2,7-naphthyridine- 4-carbonitrile >380 699, 1183... 

Reaction of 9-fluoro-8-isothiocyanato- and 8-iso(thio)cyanato-3,5, 6,7-tetrahydro-2//-pyrido[l,2,3-de]-l,4-benzoxazines with 2-amino-4,4-dimethylpyrroline, then with Br2, and with ethyl pipecolinate yielded 8-(6, 6-dimethyl-3,5,7,7-tetrahydropyrrolo[2,l-c][l,2,4]thiadiazol-3-ylidenamino)-9-fluoro and 8-(l,3-dioxo and l-oxo-3-thioxoperhydroimidazo[l,5-a]-pyridin-2-yl) derivatives, respectively (89EUP406993). Treatment of 9-fluoro-8-(2-hydroxymethylpiperidinothiocarbonylamino)-3,5,6,7-tetrahydro-2//-pyrido[l,2,3-de]-l,4-benzoxazine with HC1 gas in EtOH gave the 8-(perhy-dropyrrolo[l,2-c]thiazol-3-ylidenamino) derivative. 

Dimethyl 3,6-dimethyl-2,5-pyrazinedicarboxylate Dimethyl 5.6-dimethyl-2,3-pyrazinedicarboxylate Dimethyl 5,6-dioxo-l,4,5,6-tetrahydro-2,3-pyrazinedicarboxylate... 

Furan 2-Aminomethyl-5-(2,4-dioxo-1,2,3,4-tetrahydro-pyrimidino)-2,5-dihydro- IV/lc, 578 Imidazo(l,2-a]pyridin 1,5-Dimethyl-8-nitro-7-oxo-l,2,3,7-tetrahydro-E15/3, 2790 [cycl. (R2N)2C = CH-N02 4- Diketen] 1,3-Oxazol 4-Cyan-5-(diethoxy-methylen-amino)- E4, 565 (Het — NH2 + Orthoester) Pyrazin 3-Amino-2-methoxycarbo-nyl-5-propanoyl- E9b/2, 324 (H - CO-R)... 

Cyclohexen 4,5-Dicarboxy-l-methoxy- VII/2b, 1794 Furan 3,5-Dimethyl-2,4-dioxo-3-ethoxycarbonyl-tetrahydro- VI/2, 681... 

H-Purin 7-(2-Amino-ethyl)-1,3-dimethyl-2,6-dioxo-8-hydrazino-1,2,3,4-tetrahydro- E16a, 684 (Br -> NH-NH2)... 

Pteridin 7-Acetyl-l, 3-dimethyl-2,4-dioxo-l,2,3,4-tetrahydro- E13/2, 1318 (Acylierung)... 

H-l,2,4-Benzotriazepin 3-Hydroxy-7-methoxy-4-methyl- E9d, 460 (3-COOH - 3-H) lH-l,3,5-Benzotriazepin 1,5-Dimethyl-2,4-dioxo-2,3,4,5-tetrahydro- E4, 1158 (1,3-Diamin + ROOC-NCO)... 

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