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2.3- dihydro imidazol pyrimidine

Keywords iV-acyl imidate, imidazolidine ketone aminal, microwave irradiation, 2,3-dihydro imidazol[ 1,2-c]pyrimidine... [Pg.264]

Dimethyl-3-(2-oxo-2-phenyl-ethyl--bromid lagert sich beim Kochen mit Triethylamin in Acetonitril in 2-(2-Imino-5-phenyl-2,3-dihydro-oxazol-3-yl)-4,6-dimethyl-pyrimidin um. Aus diesem werden durch Kochen in Alkoholen mit 4-Methyl-benzolsulfonsaure als Katalysator 2-Alkoxy-l-(4,6-dimethyl-2-pyrimidyl)-4-phenyl-imidazole oder durch Erhitzen mit primaren oder sekundaren Aminen ebenfalls in Gegenwart von 4-Methyl-benzolsulfonsaure 2-Alkylamino-l-(4,6-dimcthyl-2-pyrimidyl)-4-phe-nyl-imidazole erhalten374 ... [Pg.83]

Imidazol 2-Ethylthio-4,5-dihydro-(als Hydrobromid) IX, 901 Imidazolidin l,3-Dimethyi-2-thiono-E4, 495 (Diamin + CS2) Pyrimidin l-Methyl-2-thiono-hexahydro- E4, 495 (Diamin + CS2)... [Pg.226]

The electrolytic reduction of purine, which has been reviewed [313, 314, 361], takes place only in acid solution and thus differs from that of pyrimidine and quinazoline. The reduction proceeds in acid solution in two two-electron steps, the first resulting in a 3,4-dihydro derivative, whereas the tetrahydro compound formed in the second step is hydrolyzed to formaldehyde and an imidazole derivative. [Pg.701]

Many ring-fused imidazole derivatives have been synthesized by various methods. Domino Michael addition retro-ene reaction of 2-alkoxyiminoimidazolidines and acetylene carboxylates provided a synthesis of 2,3-dihydroimidazo[l,2-a]pyrimidin-5-(l//)-ones <05T5303>. A single step synthesis of 3,5-dialkyl-9-nitroimidazo[l,2-c]quinazolin-2(3//)-ones from simple carbonyl compounds, primary amines or amino acid methyl esters and 2-azido-5-nitrobenzonitrile has been published <05TL5778>. Diels-Alder reaction of azadienes and benzimidazole-4,7-diones afforded imidazo[4,5-g ]quinoline-4,9-dione derivatives <05EJ01903>. Reaction between isocyanides and dialkyl acetylenedicarboxylates in the presence of 4,5-diphenyl-l,3-dihydro-2//-imidazol-2-one provided a one-pot synthesis of 5//-imidazo[2,l-ft][l,3]oxazine derivatives <05T2645>. Microwave irradiation was employed in the synthesis of 1-ary 1-3-acetyl-1,4,5,6-... [Pg.231]

Amino-6-nitro-2,3-dihydro- und entsprechende Pyrimidino[l,2-a]pyrimidine werden durch Hydrazin und substituierte Hydrazine unter Bildung von 4-Ni-tro-5-[(4,5-dihydro-lH-imidazol-2-yl)-amino]-l H-pyrazolen bzw. 4-Nitro-5-[(3,4,5,6-tetrahydro-2-pyrimidinyl)-amino]-l H-pyrazoIen gespalten1258. [Pg.560]

Aza-heterocycle Ring Contraction. A variety of polyaza six-ring heterocycles undergo contraction with formal excision of N, e.g. eq 14. Further heteroatoms in the ring are tolerated 1,2,3-triazines yield pyrazoles and 1,2,4-triazines yield imidazoles, with the latter usually requiring reflux temperature. The utility of indole syntheses from cinnolines " by this method should be noted. Adj acency of heteroatoms is not required conversions of pyrimidine to pyrrole and 1,3,5-triazine to imidazole have been recorded. The mechanism of these conversions is unclear, but ring dihydro derivatives are thought to be involved. [Pg.555]


See other pages where 2.3- dihydro imidazol pyrimidine is mentioned: [Pg.264]    [Pg.271]    [Pg.190]    [Pg.739]    [Pg.579]    [Pg.215]    [Pg.267]    [Pg.63]    [Pg.61]    [Pg.95]    [Pg.230]    [Pg.272]   
See also in sourсe #XX -- [ Pg.264 ]

See also in sourсe #XX -- [ Pg.264 ]

See also in sourсe #XX -- [ Pg.264 ]




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