1218-24-2Relevant articles and documents
Rhodium(III)-catalyzed dehydrogenative Heck reaction of salicylaldehydes
Shi, Zhuangzhi,Schr?der, Nils,Glorius, Frank
, p. 8092 - 8096 (2012)
Your CHOice! An efficient RhIII-catalyzed dehydrogenative Heck reaction (DHR) of salicylaldehydes with different classes of olefins extends the oxidative Heck reaction to aldehyde C-H bonds. Several structural motifs similar to natural products and bioactive molecules such as aurones, flavones, 2'-hydroxychalcones, and flavanones could be efficiently produced. Initial mechanistic studies give insight into the reaction mechanism. Copyright
Convenient synthesis of flavanone derivatives via oxa-Michael addition using catalytic amount of aqueous cesium fluoride
Miura, Motofumi,Shigematsu, Karin,Toriyama, Masaharu,Motohashi, Shigeyasu
supporting information, (2021/10/25)
A total of 36 flavanones, which included polycyclic aromatic and heterocyclic rings, were readily synthesized via oxa-Michael addition from the corresponding hydroxychalcones with a catalytic amount of aqueous cesium fluoride solution under mild conditions. This method could be applied to the scalable synthesis of eriodictyol as a known potent inhibitor of the SARS-CoV-2 spike protein.
Synthesis and cytotoxicity of novel (E)-2-phenylchroman-4-one-O-((1-substituted-1H-1,2,3-triazol-4-yl)methyl) oxime derivatives
Gutam, Madhu,Mokenapelli, Sudhakar,Yerrabelli, Jayaprakash Rao,Banerjee, Somesh,Roy, Partha,Chitneni, Prasad Rao
, p. 1883 - 1891 (2020/05/13)
A series of new flavanone-triazole hybrids (7a–m) were synthesized from flavanone oximes (6a–c) via multistep synthetic strategy, involving Cu (I) catalyzed azide, alkyne 1,3-dipolar cycloaddition by Click reaction. All the synthesized compounds were tested for their cytotoxicity against HCT-15, HeLa, NCI-H522, and HEK-293 (normal cell line) cell lines. Compounds 6a, 7a, 7b, 7d, 7e, 7j, and 7m showed the significant cytotoxicity, wherein compound 7b showed potential cytotoxicity against NCI-H522 cell line and compounds 6a and 7a were offensive with HEK-293 in their toxicity profile.
Enzyme-assisted cyclization of chalcones to flavanones
Alonso, Mariana Macías,Boluda, Carlos José,Barajas, Gabriela Díaz,Sánchez, Nallely Caldera,Córdova-Guerrero, Iván,Marrero, Joaquín González
, p. 926 - 931 (2020/12/23)
Enzyme catalyzed synthesis is an eco-friendly technique in organic synthesis, having several benefits over conventional methods. In the present work, we describe a simple process of laccase and chloroperoxidase assisted cyclization of chalcones, leading to the formation of flavanones. The reaction proceeds in a mixture of phosphate buffer and ethanol, under oxygen atmosphere at room temperature, yielding the corresponding flavanone in good to moderate yield. The relative configuration of the products at C2 is tentatively assigned as S*-flavanone based on the coupling constants with the methylenic protons H3α,β. In comparison to the chemical methods, we describe a process which can be achieved efficiently under mild conditions using oxygen as oxidant.
Functionalization of the chalcone scaffold for the discovery of novel lead compounds targeting fungal infections
Bonvicini, Francesca,Gentilomi, Giovanna A.,Bressan, Francesca,Gobbi, Silvia,Rampa, Angela,Bisi, Alessandra,Belluti, Federica
, (2019/02/01)
The occurrence of invasive fungal infections represents a substantial threat to human health that is particularly serious in immunocompromised patients. The limited number of antifungal agents, devoid of unwanted toxic effects, has resulted in an increased demand for new drugs. Herein, the chalcone framework was functionalized to develop new antifungal agents able to interfere with cell growth and with the infection process. Thus, a small library of chalcone-based analogues was evaluated in vitro against C. albicans ATCC 10231 and a number of compounds strongly inhibited yeast growth at non-cytotoxic concentrations. Among these, 5 and 7 interfered with the expression of two key virulence factors in C. albicans pathogenesis, namely, hyphae and biofilm formation, while 28 emerged as a potent and broad spectrum antifungal agent, enabling the inhibition of the tested Candida spp. and non-Candida species. Indeed, these compounds combine two modes of action by selectively interfering with growth and, as an added value, weakening microbial virulence. Overall, these compounds could be regarded as promising antifungal candidates worthy of deeper investigation. They also provide a chemical platform through which to perform an optimization process, addressed at improving potency and correcting liabilities.
Design, synthesis, molecular modelling, and in vitro evaluation of tricyclic coumarins against Trypanosoma cruzi
Coelho, Gleicekelly Silva,Andrade, Josimara Souza,Xavier, Viviane Flores,Sales Junior, Policarpo Ademar,Rodrigues de Araujo, Barbara Caroline,Fonseca, Kátia da Silva,Caetano, Melissa Soares,Murta, Silvane Maria Fonseca,Vieira, Paula Melo,Carneiro, Claudia Martins,Taylor, Jason Guy
, p. 337 - 350 (2018/12/05)
Chagas disease is caused by infection with the parasite protozoan Trypanosoma cruzi and affects about 8 million people in 21 countries in Latin America. The main form of treatment of this disease is still based on the use of two drugs, benznidazole and nifurtimox, which both present low cure rates in the chronic phase and often have serious side-effects. Herein, we describe the synthesis of tricyclic coumarins that were obtained via NHC organocatalysis and evaluation of their trypanocidal activity. Molecular docking studies against trypanosomal enzyme triosephosphate isomerase (TIM) were carried out, as well as a theoretical study of the physicochemical parameters. The tricyclic coumarins were tested in vitro against the intracellular forms of Trypanosoma cruzi. Among the 18 compounds tested, 10 were more active than the reference drug benznidazole. The trypanocidal activity of the lead compound was rationalized by molecular docking study which suggested the strong interaction with the enzyme TIM by T.?cruzi and therefore indicating a possible mode of action. Furthermore, the selectivity index of eight tricyclic coumarins with high anti-T.?cruzi activity was above 50 and thus showing that these lead compounds are viable candidates for further in vivo assays.
The detection of the precursors of the photorearranged products of 3-hydroxyflavones in selected solvents from UV-visible spectra: In situ
Tomar, Jyoti,Kaur, Kulvir,Bansal, Manisha
, p. 2912 - 2920 (2019/12/24)
Mechanistic studies relating to the photochemistry of 3-hydroxy-2-phenyl-4H-chromen-4-one (3HF) and 6-chloro-3-hydroxy-2-phenyl-4H-chromen-4-one (Cl-3HF) have been reinvestigated in selected solvents. The UV-visible spectra of the photoproduct(s) of 3HF and Cl-3HF have been computed in situ via subtracting the spectra of unreacted substrates, with acetonitrile (ACN) and methanol (MeOH) as solvents. These spectra turn out to be different from the spectra of the corresponding isolated photoproducts: 3-hydroxy-3-phenyl-indan-1,2-dione and 6-chloro-3-hydroxy-3-phenyl-indan-1,2-dione (referred to as dione). Analyses of the photoproduct(s) via GC-MS show the formation of a single detectable product, i.e., the corresponding dione. On the basis of some experimental observations, it is proposed that the primary photoproduct in situ is 2,3-epoxy-2-hydroxy-1-indanone (referred to as epoxide) instead of dione as reported in previous years. Earlier, epoxide has been proposed to be the intermediate in the mechanism for the formation of dione. This is the first report where the formation of epoxide has been directly detected in the selected solvents. On the other hand, both dione and epoxide (2?:?1) are shown to be formed with MeOH as solvent. The second important finding is that epoxide and dione interconvert in the dark, depending upon the environment. With ACN as solvent, pure dione in the dark is kinetically and partially converted to epoxide. With MeOH as solvent, epoxide is instantly and partially converted to dione until both are in equilibrium. However, a solution of dione in MeOH remains stable in the dark. The photoformation of epoxide is quantitative with ACN as solvent and it is sufficiently stable. It has been further observed that epoxide solutions of 3HF and Cl-3HF in ACN are quantitatively converted into 3-phenylisobenzofuran-1(3H)-one and 6-chloro-3-phenylisobenzofuran-1(3H)-one, i.e., the corresponding phthalides, through the loss of CO when kept in the dark for some days. A mechanism has been proposed where epoxide has been shown to give dione and/or phthalide via selective C-O or C-C bond cleavage in the oxiranyl ring, respectively. The selection of this cleavage depends mainly on the solvent system and the substituents in the parent flavones.
5′-Chloro-2,2′-dihydroxychalcone and related flavanoids as treatments for prostate cancer
Saito, Yohei,Mizokami, Atsushi,Tsurimoto, Hiroyuki,Izumi, Kouji,Goto, Masuo,Nakagawa-Goto, Kyoko
, p. 1143 - 1152 (2018/09/10)
Several flavonoids and their biosynthetic precursor chalcones were designed and synthesized to improve the biological effects of the lead compound 2′-hydroxyflavonone against androgen receptor (AR)-dependent transcriptional stimulation. Newly synthesized chalcones 19 and 26 suppressed AR-dependent transcription as well as DHT-dependent growth stimulation at a low micromolar level. These compounds were also effective against ligand-independent constitutively active mutant AR derived from castration-resistant PCa (CRPC). Compounds 19 and 26 showed broad spectrum antiproliferative activity at 5–10 μM against multiple tumor cell lines including androgen-independent and taxane-resistant prostate cancer as well as a multidrug-resistant subline. Mode of action studies suggested that 19 induced sub-G1 accumulation in PC-3 cells by disrupting the microtubule network without affecting cell cycle progression. Furthermore, the in vivo effectiveness of chalcone 19 was confirmed in a xenograft model antitumor assay. Thus, chalcone 19 has the potential to be a bifunctional lead for treatment of AR-dependent PCa at lower doses as well as AR-independent PCa, including CRPC, at higher doses.
Design of a New Bimetallic Catalyst for Asymmetric Epoxidation and Sulfoxidation
Bhadra, Sukalyan,Akakura, Matsujiro,Yamamoto, Hisashi
supporting information, p. 15612 - 15615 (2016/01/09)
A new chiral tethered 8-quinolinol-based ligand class is developed. The binuclear titanium complex of the ligand operates through a novel mechanism allowing for the regio- and stereoselective epoxidation of primary and tertiary homoallylic alcohols (up to 98% ee), as well as first examples of 2-allylic phenols (up to 92% ee). The new catalyst system also promotes the asymmetric oxidation of γ-hydroxypropyl sulfides giving an important class of chiral sulfoxides that have been inaccessible to date (up to 95% ee).
Absorption and fluorescent studies of 3-hydroxychromones
Khanna, Radhika,Kumar, Ramesh,Dalal, Aarti,Kamboj, Ramesh C.
, p. 1159 - 1163 (2015/10/20)
The synthesis and spectral studies of variously substituted 3-hydroxychromones have been carried out. A key relationship between the structural motif of synthesized 3-hydroxychromones (3-HCs) and their fluorescent properties was found. The chromones substituted with electron-donating group at 4′-position expressed the red shift of the N and T band and also exhibited the increased fluorescent intensity ratio while the chromones with electron-withdrawing group showed the blue shift of the N and T band. Therefore, these 3-HCs may behave as the possible fluorescent probes.
