3770-50-1Relevant articles and documents
Synthesis of Indoles by Reductive Cyclization of Nitro Compounds Using Formate Esters as CO Surrogates
Ahmed Fouad, Manar,Ferretti, Francesco,Formenti, Dario,Milani, Fabio,Ragaini, Fabio
supporting information, p. 4876 - 4894 (2021/09/20)
Alkyl and aryl formate esters were evaluated as CO sources in the Pd- and Pd/Ru-catalyzed reductive cyclization of 2-nitrostyrenes to give indoles. Whereas the use of alkyl formates requires the presence of a ruthenium catalyst such as Ru3(CO)12, the reaction with phenyl formate can be performed by using a Pd/phenanthroline complex alone. Phenyl formate was found to be the most effective CO source and the desired products were obtained in excellent yields, often higher than those previously reported using pressurized CO. The reaction tolerates many functional groups, including sensitive ones like a free aldehydic group or a pendant pyrrole. Detailed experiments and kinetic studies allow to conclude that the activation of phenyl formate is base-catalyzed and that the metal doesn't play a role in the decarbonylation step. The reactions can be performed in a single thick-walled glass tube with as little as 0.2 mol-% palladium catalyst and even on a 2 g scale. The same protocol can be extended to other nitro compounds, affording different heterocycles.
Design, synthesis, anticancer activity, and solid lipid nanoparticle formulation of indole-and benzimidazole-based compounds as pro-apoptotic agents targeting bcl-2 protein
Nagy, Manar I.,Darwish, Khaled M.,Kishk, Safaa M.,Tantawy, Mohamed A.,Nasr, Ali M.,Qushawy, Mona,Swidan, Shady A.,Mostafa, Samia M.,Salama, Ismail
, p. 1 - 37 (2021/02/16)
Cancer is a multifactorial disease necessitating identification of novel targets for its treat-ment. Inhibition of Bcl-2 for triggered pro-apoptotic signaling is considered a promising strategy for cancer treatment. Within the current work, we aimed to design and synthesize a new series of benzimidazole-and indole-based derivatives as inhibitors of Bcl-2 protein. The market pan-Bcl-2 inhibitor, obatoclax, was the lead framework compound for adopted structural modifications. The obatoclax’s pyrrolylmethine linker was replaced with straight alkylamine or carboxyhydrazine methylene linkers providing the new compounds. This strategy permitted improved structural flexibility of synthesized compounds adopting favored maneuvers for better fitting at the Bcl-2 major hydrophobic pocket. Anti-cancer activity of the synthesized compounds was further investigated through MTT-cytotoxic assay, cell cycle analysis, RT-PCR, ELISA and DNA fragmentation. Cytotoxic results showed compounds 8a, 8b and 8c with promising cytotoxicity against MDA-MB-231/breast cancer cells (IC50 = 12.69 ± 0.84 to 12.83 ± 3.50 μM), while 8a and 8c depicted noticeable activities against A549/lung adenocarcinoma cells (IC50 = 23.05 ± 1.45 and 11.63 ± 2.57 μM, respectively). The signaling Bcl-2 inhibition pathway was confirmed by molecular docking where significant docking energies and interactions with key Bcl-2 pocket residues were depicted. Moreover, the top active compound, 8b, showed significant upregulated expression levels of pro-apoptotic/anti-apoptotic of genes; Bax, Bcl-2, caspase-3,-8, and-9 through RT-PCR assay. Improving the compound’s pharmaceutical profile was undertaken by introducing 8b within drug-solid/lipid nanoparticle formulation prepared by hot melting homogenization technique and evaluated for encapsulation efficiency, particle size, and zeta potential. Significant improvement was seen at the compound’s cytotoxic activity. In conclusion, 8b is introduced as a promising anti-cancer lead candidate that worth future fine-tuned lead optimization and development studies while exploring its potentiality through in-vivo preclinical investigation.
Design, synthesis, and antimicrobial activity of certain new indole-1,2,4 triazole conjugates
Al-Mutairi, Maha S.,Al-Wabli, Reem I.,Alsulami, Mona A.,Attia, Mohamed I.,Bukhari, Sarah I.,Moubayed, Nadine M. S.
, (2021/05/28)
The increasing prevalence of microbial infections and the emergence of resistance to the currently available antimicrobial drugs urged the development of potent new chemical entities with eminent pharmacokinetic and/or pharmacodynamic profiles. Thus, a series of new indole-triazole conjugates 6a-u was designed and synthesized to be assessed as new antimicrobial candidates using the diameter of the inhibition zone and minimum inhibitory concentration assays against certain microbial strains. Their in vitro antibacterial evaluation revealed good to moderate activity against most of the tested Gram-negative strains with diameter of the inhibition zone (DIZ) values in the range of 11–15 mm and minimum inhibition concentration (MIC) values around 250 μg/mL. Meanwhile, their in vitro antifungal evaluation demonstrated a potent activity against Candida tropicalis with MIC value as low as 2 μg/mL for most of the tested compounds. Moreover, compound 6f is the most potent congener with an MIC value of 2 μg/mL against Candida albicans.
4-Alkyl-1,2,4-triazole-3-thione analogues as metallo-β-lactamase inhibitors
Gavara, Laurent,Legru, Alice,Verdirosa, Federica,Sevaille, Laurent,Nauton, Lionel,Corsica, Giuseppina,Mercuri, Paola Sandra,Sannio, Filomena,Feller, Georges,Coulon, Rémi,De Luca, Filomena,Cerboni, Giulia,Tanfoni, Silvia,Chelini, Giulia,Galleni, Moreno,Docquier, Jean-Denis,Hernandez, Jean-Fran?ois
supporting information, (2021/06/15)
In Gram-negative bacteria, the major mechanism of resistance to β-lactam antibiotics is the production of one or several β-lactamases (BLs), including the highly worrying carbapenemases. Whereas inhibitors of these enzymes were recently marketed, they only target serine-carbapenemases (e.g. KPC-type), and no clinically useful inhibitor is available yet to neutralize the class of metallo-β-lactamases (MBLs). We are developing compounds based on the 1,2,4-triazole-3-thione scaffold, which binds to the di-zinc catalytic site of MBLs in an original fashion, and we previously reported its promising potential to yield broad-spectrum inhibitors. However, up to now only moderate antibiotic potentiation could be observed in microbiological assays and further exploration was needed to improve outer membrane penetration. Here, we synthesized and characterized a series of compounds possessing a diversely functionalized alkyl chain at the 4-position of the heterocycle. We found that the presence of a carboxylic group at the extremity of an alkyl chain yielded potent inhibitors of VIM-type enzymes with Ki values in the μM to sub-μM range, and that this alkyl chain had to be longer or equal to a propyl chain. This result confirmed the importance of a carboxylic function on the 4-substituent of 1,2,4-triazole-3-thione heterocycle. As observed in previous series, active compounds also preferentially contained phenyl, 2-hydroxy-5-methoxyphenyl, naphth-2-yl or m-biphenyl at position 5. However, none efficiently inhibited NDM-1 or IMP-1. Microbiological study on VIM-2-producing E. coli strains and on VIM-1/VIM-4-producing multidrug-resistant K. pneumoniae clinical isolates gave promising results, suggesting that the 1,2,4-triazole-3-thione scaffold worth continuing exploration to further improve penetration. Finally, docking experiments were performed to study the binding mode of alkanoic analogues in the active site of VIM-2.
Design, Synthesis and Characterization of Novel Isoxazole Tagged Indole Hybrid Compounds
Al-Qawasmeh, Raed A.,Al-Nazer, Louy A.,Dawlat-Kari, Sarah A.,Abu-Qatouseh, Luay,Sabri, Salim S.,Aldamen, Murad A.,Sinnokrot, Mutasem
, p. 138 - 148 (2020/04/15)
Sixteen new isoxazole tagged indole compounds have been synthesized via copper (I) catalyzed click chemistry of the aryl hydroxamoyl chloride and an indole containing alkyne moiety. The chemical structure of the synthesized compounds has been established using various physicochemical techniques. X-ray single crystal analysis of Ethyl 1-((3-phenylisoxazol-5-yl) methyl)-1H-indole-2-carboxylate (8a) has been analyzed. All compounds were tested for their antibacterial and anticancer activities. The activities for the new compounds were weak against both bacterial strains and the cancer cell lines.
Scaffold Hopping of Natural Product Evodiamine: Discovery of a Novel Antitumor Scaffold with Excellent Potency against Colon Cancer
Wang, Lei,Fang, Kun,Cheng, Junfei,Li, Yu,Huang, Yahui,Chen, Shuqiang,Dong, Guoqiang,Wu, Shanchao,Sheng, Chunquan
, p. 696 - 713 (2020/02/04)
Inspired by the natural product evodiamine, a novel antitumor indolopyrazinoquinazolinone scaffold was designed by scaffold hopping. Structure-activity relationship studies led to the discovery of compound 15j, which shows low nanomolar inhibitory activity against the HCT116 cell line. Further antitumor mechanism studies indicated that compound 15j acted by the dual inhibition of topoisomerase 1 and tubulin and induced apoptosis with G2 cell-cycle arrest. The quaternary ammonium salt of compound 15j (compound 15js) exhibited excellent in vivo antitumor activity (TGI = 66.6%) in the HCT116 xenograft model with low toxicity. Indolopyrazinoquinazolinone derivatives represent promising multitargeting antitumor leads for the development of novel antitumor agents.
Synthesis, biological evaluation and in silico studies of certain oxindole–indole conjugates as anticancer CDK inhibitors
Abdel-Aziz, Hatem A.,Al-Ansary, Ghada H.,Al-Warhi, Tarfah,Aljaeed, Nada,Ayyad, Rezk R.,El Kerdawy, Ahmed M.,Eldehna, Wagdy M.,Ismael, Omnia E.
, (2020/05/05)
On account of their overexpression in a wide range of human malignancies, cyclin-dependent kinases (CDKs) are among the most validated cancer targets, and their inhibition has been featured as a valuable strategy for anticancer drug discovery. In this study, a hybrid pharmacophore approach was adopted to develop two series of oxindole–indole conjugates (6a–i and 9a–f) and carbocycle–indole conjugates (11a,b) as efficient antitumor agents with potential inhibitory action toward CDK4. All oxindole–indole conjugates, except 6i, 9b, and 9c efficiently affected the growth of the human breast cancer MCF-7 (IC50: 0.39 ± 0.05–21.40 ± 1.58 μM) and/or MDA-MB-231 (IC50: 1.03 ± 0.04–22.54 ± 1.67 μM) cell lines, whereas bioisosteric replacement of the oxindole nucleus with indane or tetralin rings (compounds 11a,b) diminished the anti-proliferative activity. In addition, hybrids 6e and 6f displayed effective cell cycle disturbance and proapoptotic capabilities in MCF-7 cells. Furthermore, the efficient anti-proliferative agents towards MCF-7 and/or MDA-MB-231 cell lines (6a–h, 9a, and 9e) were investigated for their potential inhibitory action toward CDK4. Hybrids 6a and 6e displayed good CDK4 inhibitory activity with IC50s equal 1.82 and 1.26 μM, respectively. The molecular docking study revealed that oxindole moiety is implicated in two H-bonding interactions via both (NH) and (C=O) groups with the key amino acids Glu94 and Val96, respectively, whereas the indole framework is stably accommodated in a hydrophobic sub-pocket establishing hydrophobic interactions with the amino acid residues of Ile12, Val20, and Gln98 lining this sub-pocket. Collectively, these results highlighted hybrids 6a and 6e as good leads for further optimization as promising antitumor drugs toward breast malignancy and CDK inhibitors.
4-Amino-1,2,4-triazole-3-thione-derived Schiff bases as metallo-β-lactamase inhibitors
Baud, Damien,Bebrone, Carine,Becker, Katja,Benvenuti, Manuela,Cerboni, Giulia,Chelini, Giulia,Cutolo, Giuliano,De Luca, Filomena,Docquier, Jean-Denis,Feller, Georges,Fischer, Marina,Galleni, Moreno,Gavara, Laurent,Gresh, Nohad,Kwapien, Karolina,Legru, Alice,Mangani, Stefano,Mercuri, Paola,Pozzi, Cecilia,Sannio, Filomena,Sevaille, Laurent,Tanfoni, Silvia,Verdirosa, Federica,Berthomieu, Dorothée,Bestgen, Beno?t,Frère, Jean-Marie,Hernandez, Jean-Fran?ois
supporting information, (2020/09/16)
Resistance to β-lactam antibiotics in Gram-negatives producing metallo-β-lactamases (MBLs) represents a major medical threat and there is an extremely urgent need to develop clinically useful inhibitors. We previously reported the original binding mode of 5-substituted-4-amino/H-1,2,4-triazole-3-thione compounds in the catalytic site of an MBL. Moreover, we showed that, although moderately potent, they represented a promising basis for the development of broad-spectrum MBL inhibitors. Here, we synthesized and characterized a large number of 4-amino-1,2,4-triazole-3-thione-derived Schiff bases. Compared to the previous series, the presence of an aryl moiety at position 4 afforded an average 10-fold increase in potency. Among 90 synthetic compounds, more than half inhibited at least one of the six tested MBLs (L1, VIM-4, VIM-2, NDM-1, IMP-1, CphA) with Ki values in the μM to sub-μM range. Several were broad-spectrum inhibitors, also inhibiting the most clinically relevant VIM-2 and NDM-1. Active compounds generally contained halogenated, bicyclic aryl or phenolic moieties at position 5, and one substituent among o-benzoic, 2,4-dihydroxyphenyl, p-benzyloxyphenyl or 3-(m-benzoyl)-phenyl at position 4. The crystallographic structure of VIM-2 in complex with an inhibitor showed the expected binding between the triazole-thione moiety and the dinuclear centre and also revealed a network of interactions involving Phe61, Tyr67, Trp87 and the conserved Asn233. Microbiological analysis suggested that the potentiation activity of the compounds was limited by poor outer membrane penetration or efflux. This was supported by the ability of one compound to restore the susceptibility of an NDM-1-producing E. coli clinical strain toward several β-lactams in the presence only of a sub-inhibitory concentration of colistin, a permeabilizing agent. Finally, some compounds were tested against the structurally similar di-zinc human glyoxalase II and found weaker inhibitors of the latter enzyme, thus showing a promising selectivity towards MBLs.
A NaH-promoted N-detosylation reaction of diverse p-toluenesulfonamides
Sun, Wanwan,Chen, Xiaobei,Hu, Ying,Geng, Huihui,Jiang, Yuanrui,Zhou, Yuxin,Zhu, Wenjing,Hu, Min,Hu, Haohua,Wang, Xingyi,Wang, Xinli,Zhang, Shilei,Hu, Yanwei
supporting information, (2020/10/05)
A NaH-mediated detosylation reaction of various Ts-protected indoles, azaheterocycles, anilines and dibenzylamine was reported. The method features cheap reagent, convenient operations, mild reaction conditions and broad substrate scope. Moreover, this study revealed that the loading of NaH in tosylation reactions of nitrogen-containing compounds with NaH as a base in DMA or DMF should be controlled due to the possibility of adverse detosylation.
Reusable, homogeneous water soluble photoredox catalyzed oxidative dehydrogenation of N-heterocycles in a biphasic system: Application to the synthesis of biologically active natural products
Abinaya, R.,Baskar, B.,Mariappan, M.,Prasanth, Arun,Sridhar, R.,Srinath, S.
, p. 2575 - 2587 (2020/05/13)
Herein, a simple and efficient method for the oxidative dehydrogenation (ODH) of tetrahydro-β-carbolines, indolines and tetrahydro-(iso)quinolines is described using a reusable, homogeneous cobalt-phthalocyanine photoredox catalyst in a biphasic medium. A biphasic system offers an advantage of easy separation of the product and an efficient reusability of the homogeneous photoredox catalyst. Also, the current system significantly helps to overcome the solubility issue of the substrate and catalyst at room temperature. Its potential applications to organic transformations are demonstrated by the synthesis of various biologically active N-heterocycles such as indoles, (iso)quinolines and β-carbolines and natural products such as eudistomin U, norharmane, and harmane and precursors to perlolyrine and flazin. Without isolation and purification, the catalyst solution can be reused up to 5 times with almost comparable reactivity. Furthermore, the efficiency of the reaction was demonstrated on a gram scale. To the best of our knowledge, this is the first report on ODH reactions using a non noble, reusable and homogeneous cobalt photoredox catalyst under environmentally friendly conditions.
