74447-76-0Relevant academic research and scientific papers
Molecular recognition of isomeric protonated amino acid esters monitored by ESI-mass spectrometry
Liesenfeld, Andrea,Lutzen, Arne
, p. 825 - 831 (2014)
Two new 9,9'-spirobifluorene-derived crown ethers were prepared and used to recognise constitutionally isomeric amino acid derivatives. The performance of the receptors was evaluated by ESI-mass spectrometry using the isomer labelled guest method (ILGM).
Palladium-catalyzed dynamic kinetic asymmetric transformation of racemic biaryls: Axial-to-central chirality transfer
Yang, Liu,Zheng, Huayu,Luo, Lei,Nan, Jiang,Liu, Jingjing,Wang, Yaoyu,Luan, Xinjun
, p. 4876 - 4879 (2015)
The first dynamic kinetic asymmetric transformation of racemic biaryl substrates on the basis of axial-to-central chirality transfer has been realized. Chiral Pd-NHC complexes were found to catalyze the dynamic kinetic asymmetric spiroannulation of 4-(2-bromoaryl)-naphthalen-1-ols (or 2′-bromo-[1,1′-biphenyl]-4-ols) with internal alkynes, affording a series of enantioenriched spirocyclic products bearing an all-carbon quaternary stereocenter in good yields (up to 95%) with excellent enantioselectivities (up to 97% ee).
Construction of Chiral Tetraorganosilicons by Tandem Desymmetrization of Silacyclobutanes/Intermolecular Dehydrogenative Silylation
Zhang, Qing-Wei,An, Kun,Liu, Li-Chuan,Zhang, Qi,Guo, Huifang,He, Wei
, p. 1125 - 1129 (2017)
We report a method to construct chiral tetraorganosilicons by tandem silacyclobutane (SCB) desymmetrization–dehydrogenative silylations. A wide array of dibenzosiloles with stereogenic quaternary silicon centers were obtained in good yields and enantioselectivities up to 93 % ee. Chiral TMS-segphos was found to be a superior ligand in terms of reactivity and enantioselectivity.
Rhodium-Catalyzed Synthesis of Chiral Monohydrosilanes by Intramolecular C?H Functionalization of Dihydrosilanes
Ma, Wenpeng,Liu, Li-Chuan,An, Kun,He, Tao,He, Wei
supporting information, p. 4245 - 4251 (2020/12/25)
The preparation of chiral monohydrosilanes remains a rarely achieved goal. To this end a Rh-catalyzed desymmetrization of dihydrosilanes by way of intramolecular C(sp2)?H functionalization under simple and mild conditions has now been developed
Further lead optimization on Bax activators: Design, synthesis and pharmacological evaluation of 2-fluoro-fluorene derivatives for the treatment of breast cancer
Liu, Gang,Kim, Hyejin,Wang, Pingyuan,Fricke, Doerte R.,Chen, Haiying,Wang, Tianzhi,Shen, Qiang,Zhou, Jia
, (2021/04/19)
To further pursue potent Bax activators with better safety profiles for the treatment of breast cancer, structural optimization was conducted based on lead compound CYD-4-61 through several strategies, including scaffold hopping on the 2-nitro-fluorene ring, replacement of the nitro group with bioisosteres to avoid potential toxicity, and further optimization on the upper pyridine by exploring diverse alkylamine linkers as a tail or replacing the pyridine with bioisosteric heterocycles. F-containing compound 22d (GL0388) exhibited a good balance between the activity and toxicity, displaying submicromolar activities against a variety of cancer cell lines with 5.8–10.7-fold selectivity of decreased activity to MCF-10A human mammary epithelial cell line. Compound 22d dose-dependently blocked colony formation of breast cancer cells and prevented the migration and invasion of MDA-MB-231 cells. Mechanism of action studies indicate that 22d activated Bax, rendering its insertion into mitochondrial membrane, thereby leading to cytochrome c release from the mitochondria into the cytoplasm, subsequently inducing release of apoptotic biomarkers. Further in vivo efficacy studies of 22d in human breast cancer xenografts arisen from MDA-MB-231 cells demonstrated that this drug candidate significantly suppressed tumor growth, indicating the therapeutic promise of this class of compounds for the treatment of breast cancer as well as the potential for developing F-radiolabeled imaging ligands as anticancer chemical probes.
Synthesis of Dibenzosiloles through Electrocatalytic Sila-Friedel-Crafts Reaction
Han, Pan,Yin, Mengyun,Li, Haiqiong,Yi, Jundan,Jing, Linhai,Wei, Bangguo
supporting information, p. 2757 - 2761 (2021/04/16)
A novel electrocatalyzed method for the preparation of dibenzosiloles was developed through intramolecular C?H/Si?H dehydrogenative coupling strategy starting from biarylhydrosilanes. Both electro-donating and electro-withdrawing substitution groups were tolerated for this transformation, and the desired dibenzosilole products could be obtained in moderate to excellent yields. A sila-Friedel-Crafts reaction mechanism was proposed on the basis of previous literature and our controlled experiments. (Figure presented.).
Palladium-catalyzed relay C–H functionalization to construct novel hybrid-arylcyclophosphorus ligand precursors
Bai, Peng-Bo,Wang, Juan,Yang, Shang-Dong
supporting information, (2021/11/17)
A new relay C–H functionalization of di([1,1′-biphenyl]-2-yl)phosphine oxide to obtain esterified and hydroxylated products with different hypervalent iodines as oxidants under palladium catalysis is disclosed. This reaction provides a more effective and concise strategy for the synthesis of novel structural hybrid-arylcyclophosphorus ligand precursors with a wide range of substrates and good functional group tolerance.
Dephosphinylative [4 + 2] Benzannulation of Phosphinyl Ynamines: Application to the Modular Synthesis of Polycyclic Aromatic Amines
Okuda, Yasuhiro,Fujimoto, Mayo,Akashi, Haruo,Orita, Akihiro
supporting information, p. 17651 - 17666 (2021/12/13)
A series of 9-amino-10-halophenanthrenes were synthesized through a one-pot process, including dephosphinylative Sonogashira–Hagihara coupling of 2-bromobiphenyls with air-stable phosphinyl ynamines, followed by halonium-promoted [4 + 2] benzannulation of the resulting 2-(aminoethynyl)biphenyls. Nonsubstituted and methyl-substituted 2-bromobiphenyls rapidly underwent the Sonogashira–Hagihara aminoethynylation and the halogenative Friedel–Crafts benzannulation to provide the corresponding amino(halo)phenanthrenes in high yields, while electron-sufficient and -deficient substrates did slowly undergo the former and the latter to result in low yields, respectively. This protocol worked well for the syntheses of highly π-extended aminophenanthrenes and aminobenzonaphthothiophenes with different optical properties. Further application of this approach between 2,2″- and 2′,5′-dibromo-p-terphenyls with phosphinyl ynamines led to the regioselective formation of 6,13-diamino-5,12-dihalo- and 5,12-diamino-6,13-dihalo-dibenz[a,h]anthracenes via dual aminoethynylation and [4 + 2] benzannulation. The obtained analogues showed different ultraviolet–visible absorption and photoluminescence spectra with different emission quantum yields in CH2Cl2 solution and the powder state.
Ag-Catalyzed Cyclization of Arylboronic Acids with Elemental Selenium for the Synthesis of Selenaheterocycles
Gao, Wen-Xia,Huang, Xiao-Bo,Liu, Miao-Chang,Wu, Hua-Yue,Zhang, Xue,Zhou, Yun-Bing
supporting information, p. 5639 - 5644 (2020/11/30)
A general method for the synthesis of five-membered and six-membered selenaheterocycles through Ag-catalyzed C?Se bond-forming reaction is reported. This reaction proceeds via intramolecular cyclization of arylboronic acids with selenium powder. Preliminary mechanism studies demonstrate that this transformation involves a selenium-centred radical intermediate. (Figure presented.).
Carbonylative Suzuki-Miyaura couplings of sterically hindered aryl halides: Synthesis of 2-aroylbenzoate derivatives
Bayer, Annette,Ismael, Aya,Skrydstrup, Troels
supporting information, p. 1754 - 1759 (2020/03/17)
We have developed a carbonylative approach to the synthesis of diversely substituted 2-aroylbenzoate esters featuring a new protocol for the carbonylative coupling of aryl bromides with boronic acids and a new strategy to favour carbonylative over non-carbonylative reactions. Two different synthetic pathways-(i) the alkoxycarbonylation of 2-bromo benzophenones and (ii) the carbonylative Suzuki-Miyaura coupling of 2-bromobenzoate esters-were evaluated. The latter approach provided a broader substrate tolerance, and thus was the preferred pathway. We observed that 2-substituted aryl bromides were challenging substrates for carbonylative chemistry favouring the non-carbonylative pathway. However, we found that carbonylative Suzuki-Miyaura couplings can be improved by slow addition of the boronic acid, suppressing the unwanted direct Suzuki coupling and, thus increasing the yield of the carbonylative reaction.
