Pyrazino pyridines

Phthalimidobutyl)-2,3,4,4u,5,6-hexahydro-l//-pyrazino[l,2-u]quino-line was obtained in the reaction of 2,3,4,4u,5,6-hexahydro-l//-pyrazino[l,2-u]quinoline and A-(4-bromobutyl)phthalimide in boiling MeCN in the presence of K2CO3 (97MIP12). 2,3,4,4u,6,7-He-xahydro-l//-pyrazino[l,2-ujquinolines were N-alkylated with 3-dimethylaminomethyl-l//-pyrrolo[2,3-6]pyridine and a mixture of l//-pyrrolo[2,3-6]pyridine and 37% aqueous H2CO in aqueous AcOH in the presence of NaOAc (96USP5576319). 3-[3-Substituted 2-propen-l-yl]-2,3,4,4u, 5,6-hexahydro-l//-pyrazino[l,2-u]qui-... 

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-... 

The amino group of 10-amino-2-cyclohexylcarbonyl-l,3,4,6,7,llfc-hex-ahydro-2H-pyrazino[l,2-b]isoquinolin-4-one was acylated with AcCl in pyridine and rhodamine (07BML4154). 

Reaction of l-(3,4-dimethoxybenzyl)-9-hydroxy-l,2,3,4-tetrahydro-8//-pyrido[l,2-a]pyrazin-8-one with 37% formaldehyde solution gave a tetracyclic tetrahydroprotoberberine analogue in a Mannich-type reaction (78AJC187). Reactions of 2,3,4,4a,5,6-hexahydro-l//-pyrazino[l,2-a]-quinolines with 1 W-pyrrolo[2,3-h]pyridine in the presence of 37% aqueous CH20 and AcONa in AcOH, and with 3-dimethylaminomethyl-l //-pyrrolo[2,3-h]pyridine afforded 3-[(l//-pyrrolo[2,3-h]pyridin-3-yl)methyl] derivatives (94MIP6 96USP5576319). 

Treatment of a diastereomeric mixture of l-hydroxy-3-[2,2-bis(methoxy-carbonyl)ethyl]-1,2,3,6,11,1 la-hexahydro-4//-pyrazino[l, 2-f>] isoquinolin-4-ones (136, R = COOMe) with TiCl4-pyridine afforded the tetracyclic derivatives 137 [85JAP(K)85/258182 87TL4065], Cyclization of the monoesters 136 (R = H) was unsuccessful. 

Disubstituted and unsubstituted l,2,5-thiadiazolo[3,4- ]quinoxaline-4,9-diones (110) have been prepared in good yield by condensation of 5,6-diaminobenzo[c][l,2,5]thiadiazole with a-dicarbonyl reagents (Equation (62)) <92H(33)337>. These quinones were then converted into 1,2,5-thiadiazolo-, pyrazino-fused TCNQ analogues by condensation with malononitrile in the presence of TiCl4 in dry pyridine. The x-ray crystal structure determination of the product derived from compound (110 R1 = R2 = H) has been accomplished. 

Amino-3-mercapto-pyrazine lassen sich mit Kalium-O-ethyl-dithiocarbonatin siedendem Pyridin mit sehr guten Ausbeuten in 2-Mercapto-[Pg.882]

A fundamental process in biology is the proliferation of cells mediated by the cell cycle. On the basis of previous studies, Kuo et al. identified the pyrazino-pytidine compound 360 as a potent vascular endothelial growth factor inhibitor and the pyrimidino-pyridine species 361 as a moderately potent cyclin-dependent kinase (CDK) inhibitor (Figure 36). A proposed combination of CGP-60474 and compound 361 led to the discovery of the [l,3,5]triazino-pyridines 362 as a new series of potent CDK inhibitors <2005JME4535>. 

The ring fused onto the parent has the suffix o common names are used (with modification) where possible to simplify the name. Some examples are pyrido for pyridine, pyrrolo for pyrrole, thieno for thiophene, furo for furan, imidazo for imidazole, pyrimido for pyrimidine, pyrazino for pyrazine, among others. 

Pyridine added to a vigorously stirred suspension of 7,14-dihydroxy-6H,13H-pyrazino[l,2-a 4,5-a ]diindole-6,13-dione (prepn. s. 925) in methylene chloride, then sulfur monochloride added dropwise, and the product isolated after 10 min. stirring 6a,13a-epidithio-6a,7,13a,14-tetrahydro-6H,13H-pyrazino[l,2-a 4,5-a ]-diindole-6,7,13,14-tetraone. Y 65%. Also S,S,S-bridge with a large excess of S2CI2 s. D. L. Coffen et al., J. Org. Chem. 42, 948 (1977). 

Protonation reactions, 370 [Pt(dddt)2]FeCl4, 191 P-type conductors, 648 PVK-bonded dinitrophthalocyanine, 566 PVK-graft-polyisoprene, 566 Pyrazino-fused TCNQs, 246 Pyrazinotetrathiafulvalene, 170 Pyrazoline, 541 Pyridine-TCNQ, 238 Pyrolysis of polyacrylonitrile, 624 Pyromellitic dianhydride (PMDA), 92, 93 Pyropolymers, 762... 

Figure 6.20 Pyrazino[2,l-a]pyrido[2,3-c][2]benzazepine is a compound in which two different prefix rings, pyrazine and pyridine, are fused to two different bonds of the suffix ring, in this case [2]benzazepine. Each fusion has its own bracket term.

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