131557-53-4Relevant academic research and scientific papers
Studies on complex π-π and T-stacking features of imidazole and phenyl/p-halophenyl units in series of 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carboxamides and their carbonitrile derivatives: Role of halogens in tuning of conformation
Das, Aniruddha
, p. 520 - 540 (2017/07/07)
5-amino-1-(phenyl/p-halophenyl)imidazole-4-carboxamides (N-phenyl AICA) (2a-e) and 5-amino-1-(phenyl/p-halophenyl)imidazole-4-carbonitriles (N-phenyl AICN) (3a-e) had been synthesized. X-ray crystallographic studies of 2a-e and 3a-e had been performed to identify any distinct change in stacking patterns in their crystal lattice. Single crystal X-ray diffraction studies of 2a-e revealed π-π stack formations with both imidazole and phenyl/p-halophenyl units in anti and syn parallel-displaced (PD)-type dispositions. No π-π stacking of imidazole occurred when the halogen substituent is bromo or iodo; π-π stacking in these cases occurred involving phenyl rings only. The presence of an additional T-stacking had been observed in crystal lattices of 3a-e. Vertical π-π stacking distances in anti-parallel PD-type arrangements as well as T-stacking distances had shown stacking distances short enough to impart stabilization whereas syn-parallel stacking arrangements had got much larger π-π stacking distances to belie any syn-parallel stacking stabilization. DFT studies had been pursued for quantifying the π-π stacking and T-stacking stabilization. The plotted curves for anti-parallel and T-stacked moieties had similarities to the ‘Morse potential energy curve for diatomic molecule’. The minima of the curves corresponded to the most stable stacking distances and related energy values indicated stacking stabilization. Similar DFT studies on syn-parallel systems of 2b corresponded to no π-π stacking stabilization at all. Halogen-halogen interactions had also been observed to stabilize the compounds 2d, 2e and 3d. Nano-structural behaviour of the series of compounds 2a-e and 3a-e were thoroughly investigated.
New application of heterocyclic diazonium salts. Synthesis of pyrazolo[3,4-d][1,2,3]triazin-4-ones and imidazo[4,5-d][1,2,3]triazin-4-ones
Colomer, Juan Pablo,Moyano, Elizabeth Laura
supporting information; scheme or table, p. 1561 - 1565 (2011/05/05)
The pyrazolo[3,4-d][1,2,3]triazin-4-ones 3 and imidazo[4,5-d][1,2,3] triazin-4-ones 4 are analogs structurally related to purines that have showed a wide and significant variety of biological activity. These compounds were synthesized by one-pot diazotization of 5-amino-1H-pyrazole-4-carbonitriles 1 and 5-amino-1H-imidazole-4-carbonitriles 2, respectively.
Synthesis and Characterization of New Substituted Adenines
Basyouni, W. M.,Hosni, Hanaa M.
, p. 251 - 268 (2007/10/03)
Reaction of the 5-aminoimidazole-4-carbonitrile 3 with hydroxylamine hydrochloride, followed by cyclization with triethyl orthoformate gave the 6-aminopurine-1-oxide derivative 5. Quaternization of 5 with alkyl iodides afforded the unexpected purinium iodide salts 7, which were obtained also from reacting the 6-aminopurine 6 with the same alkyl iodides. Treatment of 7 with alkali gave the rearranged products 9. The triazolopurines 15 and 16 were synthesized from the 6-hydrazinopurine 13 and 1-amino-6-iminopurine 12 respectively. Rearrangement of 15 to the triazole 16 was also carried out. The 3-(5-amino-1-(p-chlorophenyl)imidazol-4-yl)-1,2,4-triazole 17 was obtained from treating 16 with alkali. The imidazotriazolotriazine 18 and substituted triazoles 19 and 20 were afforded from reacting 17 with nitrous acid and dimethyl sulfate respectively. Reaction of 3 with methyl-, ethyl- and phenyl-isothiocyanates gave the imidazothiazine derivatives 22. Whereas, when the reaction was carried out with n-butyl-isothiocyanate, the 6-(n-butyl)amino-2-(n-butyl)dithiocarbamylpurine 23 was obtained.
A Facile Synthesis of 5-Amino-4-cyano-1-arylimidazoles and 5-Amino-1-aryl-4-(cyanoformimidoyl)-1H-imidazoles from N-Aryl-N'-formamidines
Alves, M. Jose,Booth, Brian L,Al-Duaij, Omar Kh.,Eastwood, Paul,Nezhat, Lida,et al.
, p. 2701 - 2719 (2007/10/02)
Starting from readily available ethyl (Z)-N-(2-amino-1,2-dicyanovinyl)formimidate, N-aryl-N'-formamidines (2) can be prepared in good yields by reaction with aromatic amines at room temperature in the presence of an acid catalyst
5-Amino-4-cyano-1-(hetero)arylimidazoles
Frank, I.,Zeller, M.
, p. 2519 - 2526 (2007/10/02)
5-Amino-4-cyano-1-(hetero)arylimidazoles 1 are prepared by reaction of N-(hetero)arylformamidoethylesters 2 with 2-aminomalodinitrile in acetic acid.
