Bond Variant A3q

Only one of the three possible variants of formation of the imidazo[l,5-a]quinoxa-line system on the basis of reactions of quinoxaline and equivalents of monoatomic 

Decreasing the reaction duration to 9 h in the case of benzaldehyde gives 1-phenylimidazoquinoxaline 12a in only 58 % yield. Amine hydrochloride Ic reacts with carbon disulfide in methanol in the presence of KOH to give 1-sulfanylimidazoquinoxaline 12b (Table 4.1) (Mamedov et al. 2003). 

There are two possible ways of designing imidazo[l,5-a]quinoxalines according to variants C the introduction of the C(l)-N(2) or N(2)-C(3) fragment into quinox-aline derivatives. However, only the first one (variant CIq) has been described in the 

In addition, compounds containing two benzoylquinoxaline moieties were introduced into this reaction. This enabled the synthesis of bis(imidazoquinoxaline)s in which the quinoxaline moieties are linked with each other through various spacers. In particular, the reaction of a,co-bis(3-benzoylquinoxalin-2-on-l-yl) derivatives 36 with benzyl- and picolylamines on heating in DMSO yields a,to-bis(l,3-diphenyl-and l-pyridyl-3-phenyl-imidazo[l,5-a]quinoxaIin-4-on-5-yl) derivatives 37a-g 

The second approach to the synthesis of bis(imidazoquinoxaline)s is based on the use of a compound containing two aminomethyl moieties, l,3-di(aminomethyl) benzene 38. 

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