Synthesis of analogs of 5(4)-aminoimidazole-4(5)-carboxamide and purines. X. Synthesis and study of properties of new analogs of bredinin aglycone

Structural Characterization of 4-Cyanoimidazolium-5-olate, 4,4-Diphenyl-5-imidazolinone, and 4,5-Dicyanoimidazole. A Novel Mesoionic Compound and Decoding of Intermolecular Hydrogen Bonds

“…Synthesis of 4-Cyanoimidazolium-5-olate (3). Three synthetic pathways to compound 3 are available: (i) treatment of a mixture of the tristrimethylsilyl derivative of compound 2 with SOCl 2 , MeOH, and NEt 3 in THF;7a (ii) initial conversion of the carbamoyl derivative (compound 2 ) to the thiocarbamoyl derivative by P 4 S 10 , followed by treatment with HgCl 2 in EtOH (95%) and 20% aqueous MeNH 2 ;7b and (iii) nitrosation of 2-cyano- N -formylacetamide and reduction of the hydroxyimino group by sodium dithionite, thus providing a one-step ring closure sequence . The last method is the most convenient and affords satisfactory yields.…”

“…4-Cyanoimidazolium-5-olate ( 3 ) showed cytostatic and anticancer activity, e.g. against sarcoma-180 and Lewis lung carcinoma P-388. 7a,b We have recently used compound 3 as a coupling agent for the synthesis of heterocyclic azo dyes and we have undertaken a structural analysis using X-ray, IR, and NMR techniques, as a contribution for understanding relationships between structures and biological and nonlinear optical properties. Compound 3 is a 5(4)-substituted imidazol-4(5)-one and therefore can exist in the eight different tautomeric forms 3a − h because of both annular and keto−enol tautomerism …”