5-Imidazolo-7-methyl-2-

When treated with DBU at elevated temperature, l-[(benzotriazol-l-yl)methyl -2-aminopyridine salts 741 eliminate rather the N-H proton than the C-H one. Intermediates 742 can be trapped with aromatic aldehydes to create betaines 743. The consecutive cyclocondensation and elimination of benzotriazole results in formation of imidazolo[l,2-rz]pyridines 744 in good yields (Scheme 117) <2000JOC9201>. Aldehydes with enolizable a-protons fail to give bicyclic systems 744, producing corresponding enamines instead. 

Entsprechend cyclisieren a, co- Diamino-alkane mit zwei Molekulen (1-Ethoxy-ethylidenamino)-malonsaure-amid-nitril zu a,a>-Bis-[5-amino-4-aminocarbonyl-2-methyl-imidazolo]-alkanen243 ... 

N-CH3 2 c6h5 3-Methoxycarbonyl-7-methyl-3-phenyl-5H-6,7-dihydro-imidazolo [7,2-c] imidazol) 60 117... 

Bei der Umsetzung von Diimidazolo-methan mit Iodmethan, 3-Brom-propen oder Benzylchlo-rid werden beide Imidazol-Ringe quaterniert461 (Bis-[3-methyl-imidazolo]-, Bis-[3-allyl-imid-azolo]-, Bis [3-benzyl-imidazolo -methan). 

Amino-l,3,4-oxadiazole konnen fur die Einfuhrung heterocyclischer Substituenten iiber eine Ringumwandlung eines anderen labilen Heterocyclus genutzt werden. So reagiert 2-Amino-5-phenyl-l,3,4-oxadiazol mit 4-Benzyliden-2-methyl-5-oxo-4,5-dihydro-l,3-oxazol zu 2-(4-Benzyliden-2-methyl-5-oxo-4,5-dihydro-lH-imidazolo)-5-phenyl-1,3,4-oxadiazol649 (70% Schmp. 258°). 

IQ 2-amino-3-methyl imidazo[4,5-/ quinoline nh2 r CH3 MelQx 2-amino-3,8-dimethyl imidazo [4,5-/ quinoxaline nh2 MelQ 2-amino-3,4-dimethyl imidazolOS quinoline nh2 W XH3... 

Methylhypoxanthine, AG97 8-Methylhypoxanthine, AG98 Methylimidazoletrione, AC52 6-Methyl-7 imidazolo[.I, 5-.d]-pyrimidine, AG9 ... 

IH-[Pg.1154]

Difluoro-3-[(imidazolo-thiocar-bonyloxy-methyl]-2-phenyl- 2472... 

Durch cine -Substitution an l-(2,6-Dimethyl-4-phenyl-pyridiniono)-2-methyl-lH-pyrazo-lium-bis-[tetrafluoroborat] (Reaktionsverlauf analog S. 587) mit 1 H-Pyrazol (Wasser 15 d 20°) oder Imidazol (Wasser 12h 20°) wird l-Methyl-5,l -bi-(lH-pyrazolyl) [73% Sdp. 85°/ 0,2 Torr (0,026 kPa)] bzw. 5-Imidazolo-l-methyl-lH-pyrazoi[ 5% Schmp. 54,5-55° Sdp. 80°/ 0,002Torr (2,6 10 4kPa)] gebildet169. 

Beim Erhitzen iiber den Schmelzpunkt ergeben 2-(Ureido-methyl)- und 2-(Thioureido-methyl)-1,3-benzothiazole Imidazolo[5,l-b]-l,3-benzothiazole985 ... 

HydrOxy-propyl)-4-methyl- 41 5-(3-Hydroxy-propyl)-4-methyl- 41 4-Hydroxy-2-(2-pyridyl-methyl)- 11 2-Hydroxy-5-thiocyanat- 252 Imidazolo 215... 

A mixture of 3-chloroacetyl-6,7-dihydro-6,6-dimethyl-1-(2-methyl-4-chlorophenyl)-5/7-imidazolo[2,3- ][l,3]thiazinylium-2-olate and dimethyl acetylenedicarboxylate in DMF stirred at room temp, for 1 day -> 6-chloroacetyl-3,4-dihydro-7,8-bis(methoxy-carbonyl)-3,3-dimethyl-27/-pyrrolo[2,l-Z>][l,3]thiazine. Y 96%. F.e. and reactions s. M. Ichinari et al., Heterocycles 27, 227-35 (1988). 

Mereapto-2-methyl-chinazolin 24,164. 2-Anilino-thiazol 27,155, H 205. 2-Ammo-4-phenyl-thieizol 27, 204, II252. 2.3.Dibydro-imidazolo [1.2.bj benzisothlazid 27 n 636. 

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