17099-16-0Relevant academic research and scientific papers
Synthesis, antiprotozoal activity, and cheminformatic analysis of 2-phenyl-2h-indazole derivatives
Aguilera-Perdomo, Jacobo David,Cortés-Benítez, Francisco,Cortés-Gines, Miguel,Del Angel, Kevin Samael Olascoaga,Pérez-Villanueva, Jaime,Palacios-Espinosa, Juan Francisco,Quintana-Salazar, Edgar A.,Rodríguez-Villar, Karen,Soria-Arteche, Olivia,Yépez-Mulia, Lilián
, (2021/05/28)
Indazole is an important scaffold in medicinal chemistry. At present, the progress on synthetic methodologies has allowed the preparation of several new indazole derivatives with interesting pharmacological properties. Particularly, the antiprotozoal activity of indazole derivatives have been recently reported. Herein, a series of 22 indazole derivatives was synthesized and studied as antiprotozoals. The 2-phenyl-2H-indazole scaffold was accessed by a one-pot procedure, which includes a combination of ultrasound synthesis under neat conditions as well as Cadogan’s cyclization. Moreover, some compounds were derivatized to have an appropriate set to provide structure-activity relationships (SAR) information. Whereas the antiprotozoal activity of six of these compounds against E. histolytica, G. intestinalis, and T. vaginalis had been previously reported, the activity of the additional 16 compounds was evaluated against these same protozoa. The biological assays revealed structural features that favor the antiprotozoal activity against the three protozoans tested, e.g., electron withdrawing groups at the 2-phenyl ring. It is important to mention that the indazole derivatives possess strong antiprotozoal activity and are also characterized by a continuous SAR.
Facile synthesis of 4-substituted 1,2,4,5-tetrahydro-1,4-benzodiazepin-3-ones by reductive cyclization of 2-chloro-N-(2-nitrobenzyl)acetamides
Sasiambarrena, Leandro D.,Barri, Ivan A.,Fraga, Guido G.,Bravo, Rodolfo D.,Ponzinibbio, Agustín
supporting information, p. 264 - 267 (2019/01/04)
A facile and efficient method was developed for the synthesis of 1,2,4,5-tetrahydro-1,4-benzodiazepine-3-ones from 2-chloro-N-(2-nitrobenzyl)acetamides through a reductive cyclization using iron-ammonium chloride in ethanol–water in good yields. This method provides a simple approach to these benzodiazepine-3-ones which are of high value in the field of medicinal chemistry research.
Regioselective synthesis of 2 H-indazoles using a mild, one-pot condensation-cadogan reductive cyclization
Genung, Nathan E.,Wei, Liuqing,Aspnes, Gary E.
supporting information, p. 3114 - 3117 (2014/06/23)
An operationally simple and efficient one-pot synthesis of 2H-indazoles from commercially available reagents is reported. Ortho-imino-nitrobenzene substrates, generated via condensation, undergo reductive cyclization promoted by tri-n-butylphosophine to afford substituted 2H-indazoles under mild reaction conditions. A variety of electronically diverse ortho-nitrobenzaldehydes and anilines were examined. To further extend the scope of the transformation, aliphatic amines were also employed to form N2-alkyl indazoles selectively under the optimized reaction conditions.
An approach to fused pyrimidine derivatives via Schiff bases of aromatic ortho-nitrocarbaldehydes. An investigation of substituent effects on the reaction course
Ostrowski,Wolniewicz
, p. 705 - 713 (2007/10/03)
The synthesis of fused pyrimidines from the Schiff bases of aromatic ortho-nitrocarbaldehydes is reported. The Schiff bases after selective reduction of the nitro group on 10% Pd/C, followed by condensation of the amines formed with orthoesters, are transformed to the corresponding imidates. Heating of the latter in a sealed tube with an excess of ammonia (or with ammonia in ethanol) gives fused pyrimidines. The influence of various substituents in the aromatic ring of the imine moiety of the Schiff bases on the overall yield of fused pyrimidine derivatives has been investigated. Moderate electron-withdrawing groups gave the best results.
o-Nitrobenzylidene Compounds. Part 3. Formation of 4-Arylamino-3-methoxycinnoline 1-Oxides from N-o-Nitrobenzylideneanilines, Cyanide Ion, and Methanol: the Intermediacy of 2-Aryl-3-cyano-2H-indazole 1-Oxides
Johnston, David,Smith, David M.,Shepherd, Thomas,Thompson, David
, p. 495 - 500 (2007/10/02)
The N-o-nitrobenzylidene derivatives of variously substituted anilines (7) have been cyclised by potassium cyanide in methanol, to give 4-arylamino-3-methoxycinnoline 1-oxides (9), the structures of which have been confirmed by independent synthesis of one representative .These cinnoline oxides are the main products (sometimes the only isolated products) when the amine-derived ring in (7) is ortho-substituted; in other cases the cinnoline oxides are minor products formed along with 2-aryl-3-cyano-2H-indazoles (10).In the latter group of reactions, the primary cyclisation products are 2-aryl-3-cyano-2H-indazole 1-oxides (8): these have then either been reduced to the indazoles in the basic methanolic medium, or have undergone ring-opening and recyclisation to give the cinnoline oxides (9).In the other group, where indazole oxides (8) cannot usually be isolated, their intermediacy in cinnoline oxide formation remains a possibility, although other mechanistic pathways can be envisaged.Some 'borderline' cases are identified and discussed.
