89418-04-2Relevant academic research and scientific papers
The enhancement of the D-A effect of an asymmetric Schiff base by introducing acetyl groups into diaminomaleonitrile: Synthesis, red fluorescence and crystal structure
Wang, Ke,Su, Hao,Wang, Pengfei,Wang, Wenjie,Li, Hui
, p. 14268 - 14275 (2019/05/21)
An asymmetrical salen-type organic ligand was designed and synthesized by a new strategy developed using a precursor Ac-DMN, which is a diaminomaleonitrile (DMN) incorporated with an acetyl group. In this study, two types of asymmetrical ligands, namely Ac-DMN-salicylaldehyde (L0) and Ac-DMN-4-N,N-diethyl-salicylaldehyde (L1), and their Zn(ii) coordination complexes were studied. With the electron-pushing substituent, L1 showed interesting photoluminescence behaviour distinct from that of L0. In a THF solution, the maximum fluorescence emission of L1 red-shifted to 90 nm compared with that of L0. Furthermore, in a THF-H2O solution, L1 exhibited aggregation-induced emission (AIE), but L0 exhibited aggregation-caused quenching (ACQ). Upon coordination with Zn(ii), the maximum emission wavelengths in THF for both the ligands were red-shifted to 100 nm and 105 nm, respectively. The crystalline solid-state photoluminescence properties were studied based on the single-crystal structural analysis.
Alkylation of azoles: Synthesis of new heterocyclic-based AT1- non-peptide angiotensin (II) receptor antagonists
Al-Azmi, Amal,George, Paulson,El-Dusouqui, Osman M. E.
, p. 515 - 520 (2008/09/16)
(Chemical Equation Presented) Several novel analogues of Losartan 2 were synthesized as potential non-peptide angiotensin (II) receptor antagonists. In these non-peptide analogues, the tetrazole and the substituted imidazole rings of Losartan 2 were replaced, respectively, by a carboxylic acid function or its methyl ester and substituted triazole, imidazole or benzimidazole moieties. The biphenyl bromide precursor 3 (BPE) used to introduce the linker between the acid/ester function and the heterocyclic moiety was synthesized using Suzuki biphenyl coupling and then incorporated into the target molecule by simple nucleophilic substitution. The fixed N-aryl isomeric forms of several azole and benzimidazole tautomers were successfully separated by HPLC using 50% aqueous acetonitrile as eluent. Intermediate reaction products and final target compounds were fully characterized spectroscopically.
Novel 2H-1,2,3-Triazole sodium complex from N-[2-amino-1,2-dicyanovinyl]alkanamides
AL-Azmi, Amal,George, Paulson,El-Dusouqui, Osman M.E.
, p. 2183 - 2201 (2008/09/17)
Diazotization at 0 °C of N-[2-amino-1,2-dicyanovinyl]ethanamide 2a or propanamide 2b prepared from diaminomaleonitrile (DAMN) 1 using aqueous acetic acid and NaNO2 solution furnished sodium complex 3. The X-ray structure of the complex 3 showed that it is a 1:1 mixture of the neutral 2H-triazole heterocycle 4ii and its anion deprotonated at the central (N) atom of the ring, together with a sodium counter ion and two coordinated water molecules. However, when the diazotization reaction was carried out in the presence of aqueous HCl, the product was 5-cyano-2H-[1,2,3]triazole-4-carboxylic acid amide monohydrate 4ii. Diazotization of DAMN 1 using aqueous HCl furnished 1H-1,2,3-triazole-4,5-dicarbonitrile 5, whereas with acetic acid there was no reaction, and hence no route analogous to that leading to complex 3. The structure of both complex 3 and the triazole monohydrate 4ii were solved using X-ray crystallography, and the compounds under study were fully characterized using spectroscopic techniques.
Synthesis of 4,5-dicyanoimidazoles
Bukowska,Prejzner,Szczecinski
, p. 417 - 422 (2007/10/03)
The effective procedure of preparation of 2-trifluoromethyl-4,5- dicyanoimidazole (3a) from diaminomaleonitrile (1) and trifluoroacetic anhydride has been elaborated. The syntheses of five other 2-substituted imidazoles from appropriate acyl derivatives of 1 have been attempted. Out of them only 4,5-dicyanoimidazole (3b) could be obtained in good yield.
Synthesis of novel 5-amino-6-ethoxy-2-alkylpyrimidine-4-carbonitriles
Al-Azmi, Amal,Booth, Brian L.,Pritchard, Robin G.,Proenca, Fernanda J.R.P.
, p. 485 - 486 (2007/10/03)
The synthesis of highly functionlized 5-amino-6-ethoxy-2-alkylpyrimidine-4-carbonitriles under acid catalysis conditions was studied. The synthesis was performed by refluxing the N-(2-ammonio-1,2-dicyanovinyl)alkylamide chloride as N-(2-amino-1,2-dicyanovinyl)acetamide in ethanol. Pyrimidine formation implied rotation around the C1-C2 double bond of the salt at some stage of the reaction. The results showed that the imidoyl chloride was a critical intermediate in the reaction and the use of other acid catalysts gave only traces of 5-amino-6-ethoxy-2-alkylpyrimidine-4-carbonitriles.
