[en] This review is intended to generalize and systematize available information on the synthesis of imidazo[1,5-a]- and imidazo[1,2-a]quinoxalines. Relevant studies published in the last 10–15 years, as well as earlier studies less familiar to the broad chemical community, are surveyed. Major methods of formation of the imidazoquinoxaline system from substituted quinoxalines and imidazoles according to the type of bond being formed are presented. Special focus is placed on the radically new methods that enable the synthesis of various derivatives of these heterocyclic systems from available and inexpensive reagents. The mechanisms of formation of these compounds are discussed. Information on the biological activity of imidazo[1,5-a]- and imidazo[1,2-a]quinoxalines and examples of pharmaceuticals based on them are reported. The bibliography includes 179 references

[en] Published in summary form only

[en] We fabricated an IMI-O polymer containing an imidazole group that could form a complex structure between the monolayer and the metal ions at the air-water interface. Also, the monolayer behavior at the air-water interface and the electrical properties of metal-complexed Langmuir-Blodgett (LB) films were investigated by using Brewster angle microscopy (BAM) and current-voltage(I-V) measurements. The difference in the BAM images between the pure water and the aqueous metal ions is attributed to the interactions of the copolymers with the metal ions at the interface and the consequent change of the monolayer organization. In the I-V characteristics, the current for LB films with different metal ion depended on the quantity of the metal-ion complexed with the LB film due to the interaction between the metal ion and the IMI-O polymer

[en] To assess the effects of incorporation of a CF₂ group into the side chain of a 2-nitroimidazole derivative, the authors evaluated the in vitro and in vivo radiosensitizing activities of KU-2285 (a 2-nitroimidazole derivative with an N₁-substituent of -CH₂CF₂CONH(CH₂)nOH) and its related compounds in comparison with those of comparable nonfluorinated compounds. The pharmacokinetics of these compounds in murine tumors was also tested. KU-2285, KU-3202, and KU-3207 are fluorinated 2-nitroimidazole derivative compounds with similar structures. Etanidazole (a 2-nitroimidazole derivative with an N₁-substituent of -CH₂CONH(CH₂)nOH) and its related compounds, KU-3205 and KU-3206 were also tested. The in vivo radiosensitizing activities of each compound for hypoxic cells was evaluated with a standard colony formation method. The in vivo radiosensitizing activities of these compounds were tested in female C3H/He mice bearing SCCVII tumors using an in vivo/in vitro clonogenic assay. The pharmacokinetic studies were performed in C3H/He mice bearing the SCCVII tumor. Samples were analyzed by reversed-phase high-performance liquid chromatography. The in vitro radiosensitizing activities of fluorinated 2-nitroimidazoles were higher than those of the nonfluorinated compounds. Although the in vivo radiosensitizing activity of KU-2285 was higher than that of etanidazole, other fluorinated 2-nitroimidazoles showed less radiosensitizing activity than the comparable nonfluorinated compounds. The compound was eliminated from serum more rapidly with the increase in the number of CH₂ group in the side chain of the compound in each series. Although the in vitro sensitizing activity of the fluorinated compounds was higher than that of the comparable nonfluorinated compounds, the in vivo radiosensitizing activity of all fluorinated compounds but KU-2285 was lower than that of comparable etanidazole group compounds. 8 refs., 2 figs., 1 tab

[en] Because reoxygenation of solid tumors after irradiation with a hypoxic cell sensitizer has never previously been investigated, the authors assessed the reoxygenation in SCCVII tumors after treatment with KU-2285 plus single or fractionated irradiation. KU-2285 (100 mg/kg) was injected intraperitoneally into C3H mice bearing 1-cm SCCVII tumors at 30 min before a single dose of 12 Gy or three fractions of 5 Gy at 12 h intervals. Changes of the hypoxic fraction (HF) were then evaluated by the paired survival curve method. Since the radiosensitizing effect of KU-2285 was relatively persistent, the HF was only evaluable after 6 h of irradiation. The HF of untreated SCCVII tumors was 9.1%. After treatment with KU-2285 and 12 Gy, the HF was 25% at 6 h, 32% at 12 h, 24% at 24 h, and 7.6% at 72 h. The HF was lower at 6 h than that after radiation alone, but was similar at later periods. After three fractions of 5 Gy with or without KU-2285, the HF was 33% at 6 h in both groups, while it was 12% and 13% at 24 h for tumors pretreated with KU-2285 and those receiving radiation alone, respectively. However, a sensitizing effect of KU-2285 was indicated by the downward shift of the survival curves for tumors irradiated after exposure to this agent. Reoxygenation occurred quite efficiently in tumors receiving KU-2285 and 12 Gy. After fractionated irradiation, however, reoxygenation was similar in the KU-2285-pretreatment and irradiation alone groups. 11 refs., 4 figs

[en] A fluorinated 2-nitroimidazole radiosensitizer KU-2285 was given orally to 14 patients. The daily dose ranged from 0.5 to 2.0 g and the total dose given ranged from 0.8 to 28 g/m². Possible toxicities observed were vomiting in two patients, muscle cramping in one and multiple joint pain in one. All these complications were mild and transient and no other toxicity was observed. The peak serum concentration of KU-2285 was 25-30 μg/ml at the dose of 1 g/m². The cumulative toxicity of KU-2285 appears to be relatively low and further clinical trials seem to be warranted

[en] Published in summary form only

[en] A one-pot protocol for the synthesis of tetrahydroimidazo[1,2-a]pyridines, tetrahydropyrido[1,2-a]pyrimidines, and 3-cyanocoumarine derivatives was developed by condensing of various 1,n-diamines, 1,1-bis(methylthio)-2-nitroethene, substituted salicylaldehyde, and malononitrile or alkyl cyanoacetate at reflux condition in ethanol. Graphical abstract: < Image>.

[en] A one-pot efficient procedure for the synthesis of 2,4,5-triaryl-1H-imidazole derivatives in good to excellent yields by reaction between hexamethyldisilazane and arylaldehydes, benzyl alcohols, benzyl halides in the presence of molecular iodine has been developed. The remarkable advantages of this method are the simple workup procedure, high yields of products, and the availability of reagents

[en] In conclusion, an alternative procedure was developed under mild conditions for the synthesis of 2-(4-tosylimidazo-1-yl)pyridines and pyrimidines by the reaction of TosMIC with the corresponding heteroaryl N,N'-dimethyl form-amidines. This approach does not involve a nucleophilic displacement of a leaving group and constitutes a further application of amidines, in which TosMIC acts as both a nucleophile and an electrophile on the heteroaryl formamidine. This process offers advantages over previously reported procedures. Tosyl methyl isocyanide (TosMIC), a multipurpose commercially available 3-unit synthon introduced by Van Leusen, reacts with a variety of groups to give heterocycles. It is important to emphasize that treatment of TosMIC with various functional groups leads to the formation of the imidazole nucleus, such as is the case with imines, imidoyl chlorides, isothiocyanates, nitrile and ethoxy methylene amino. However, only the latter group yields N-heterocycle imidazoles