71898-84-5Relevant academic research and scientific papers
Structural Revision of Hyperibrin B and Hyperscabrones H and I by Biosynthetic Considerations, NMR Analysis, and Chemical Synthesis
Wang, Xiaohui,Nie, Xiao-Bin,Grossman, Robert B.,Ji, Teng-Fei,Yang, Xing-Wei
, p. 2059 - 2064 (2021)
Previously, Gao et al. reported the isolation and structural determination of three natural products, hyperibrin B (HB), hyperscabrone H (HH), and hyperscabrone I (HI), fromHypericum scabrum. HB and HH had different NMR spectroscopic data, but they were assigned identical structures. Furthermore, these compounds should be derived from bicyclic polyprenylated acylphloroglucinols (BPAPs) via degradation, but the assigned structural features of the prenyl and prenylmethyl groups being cis and meta-substituted on the cyclohexanone core were not consistent with their biosynthetic origin. In this note, we revise the structures of HB, HH, and HI via NMR and MS spectroscopic analyses and biosynthetic considerations. We also complete a total synthesis of the revised structure of HB as well as its analogue, hyperibrin A, to further confirm the revision. The revised structures of HB, HH, and HI have not been reported.
Photoredox-Catalyzed Cascade Reactions Involving Aryl Radical: Total Synthesis of (±)-Norascyronone A and (±)-Eudesmol
Xu, Ze-Jun,Liu, Xu-Yuan,Zhu, Ming-Zhu,Xu, Yu-Liang,Yu, Yue,Xu, Hai-Ruo,Cheng, Ai-Xia,Lou, Hong-Xiang
supporting information, p. 9073 - 9077 (2021/12/06)
Herein, we have developed two types of photoredox-catalyzed cascade reactions using diaryliodonium salts for the concise synthesis of norascyronone A and β-eudesmol. A rationally designed photoredox-catalyzed arylation/cyclization/Friedel-Crafts cascade reaction of enone was exploited to generate the norascyronone polycyclic skeleton. A visible-light-induced radical cyclization/acyloxy-migration reaction was explored to forge the decalin skeleton of eudesmol, and mechanistic studies indicated the reaction was initiated by one-electron oxidation of the enol ester.
Synthetic Strategy for Construction of Highly Congested Tetracyclic Core (6-5-7-4) of Harziane Diterpenoids
Tu, Qian,Wang, Zheyuan,Zhang, Zhongchao,Huang, Jun,Yang, Zhen
supporting information, p. 4088 - 4093 (2021/05/26)
The structurally intriguing tetracyclic core of complex harziane diterpenoid was constructed in 14 steps from commercially available 3-ethoxycyclohex-2-en-1-one. The key steps were a Mn/Cu-mediated oxidative 1,3-dicarbonyl radical cascade cyclization reac
Protecting-Group-Free Total Syntheses of (±)-Norascyronones A and B
Cao, Tingting,Zhu, Lei,Lan, Yu,Huang, Jun,Yang, Zhen
, p. 2517 - 2521 (2020/03/13)
Protecting-group-free total syntheses of natural products norascyronone A and norascyronone B were accomplished in eight steps from the commercially available starting material 1-bromo-4-methoxy-2-methylbenzene. The key step was a Mn/Cu-mediated oxidative
Synthesis and evaluation of tetrahydroquinolin-2(1H)-one derivatives as novel anti-pancreatic cancer agents via targeting autophagy
Shen, Qi,Wang, Jie,Liu, Chen-Xi,Cui, Wei,Zhang, Lei,Zhang, Yu-chao,Wang, Yue,Wu, Jing,Li, Jian-Xin
, p. 28 - 44 (2019/03/19)
Pancreatic cancer is one of the most deadly neoplasm with a 5-year survival rate of less than 6% owing to its remarkable tolerance to nutrient starvation, and new drugs and treatment strategies are urgently needed. During a project aiming at discovery of anticancer agents, we performed a structure modification on polycyclic polyprenylated acylphloroglucinols (PPAPs) skeleton, and discovered that PPAP rearranged to a tetrahydroquinolin-2(1H)-one feature. Here, series of tetrahydroquinolin-2(1H)-one derivatives were designed, synthesized and evaluated against a highly metastatic human pancreatic cancer cell line (PANC-1), and the structure-activity relationship was also discussed. Among them, derivative 11k showed the most potent inhibitory activity with an IC50 value of 4.9 μM under nutrient-deprived condition. In contrast, all these derivatives exhibited low cytotoxicity against PANC-1 cells under normal nutrient condition, suggesting that the derivatives appeared to allow alternative tumor cell death mechanisms, and led to less toxicity. Further evaluations demonstrated that 11k decreased colony formation and induced the apoptosis of PANC-1 under nutrient-deprived condition in a concentration dependent manner. In in vivo study, 11k significantly suppressed the tumor development and weight in nude mice. Preliminary mechanism research revealed that 11k clearly downregulated LC3-II expression and increased the level of p62, two key autophagy markers and critical signals for pancreatic tumor growth and progression. Our current findings demonstrated that 11k might be a promising candidate for the new chemotherapeutic molecule of pancreatic cancer, and deserve further study.
A Unique Skeletal Rearrangement of a Bicyclo[33.1]nonanetrione to a Tetrahydroquinolin-2(1 H)-one System
Shen, Qi,Liu, Fang,Zhang, Yu-Chao,Wang, Jie,Zhang, Lei,Wang, Yue,Xu, Hong-Xi,Shao, Zhuzhou,Cao, Yang,Wu, Jing,Liang, Yong,Li, Jian-Xin
supporting information, p. 1711 - 1716 (2018/07/06)
The unexpected formation of a 4-hydroxytetrahydroquinolin-2(1 H)-one from a bicyclo[3.3.1]nonanetrione system and an amino alcohol in the presence of TsOH is reported. The mechanism of this transformation was studied by DFT calculations. The reaction provides an entry to the synthesis of highly functionalized 4-hydroxytetrahydroquinolin-2(1 H)-ones.
Systemic study on the biogenic pathways of Yezo'otogirins: Total synthesis and antitumor activities of (±)-Yezo'otogirin C and its structural analogues
Yang, Wei,Cao, Jingming,Zhang, Mengxun,Lan, Rongfeng,Zhu, Lizhi,Du, Guangyan,He, Shuzhong,Lee, Chi-Sing
, p. 836 - 846 (2015/03/05)
A systematic study of the biomimetic pathways to yezootogirin C under aerobic and anaerobic conditions has been investigated, and both are found to be feasible pathways to the natural product depending on the physiological conditions. Because of the lower activation energy, the aerobic process would be more favorable when the in vivo oxygen level is high. In the course of this study, a highly efficient synthetic route to (±)-yezootogirin C has been established in four steps (31% overall yield) from a readily available compound without using any protecting groups. The natural product and its structural analogues exhibited antitumor activities against several human cancer cell lines and appeared to arrest cell cycles in different phases.
Synthesis of (±) debenzoyl analogs of norsampsones as potential anticancer agents
Jadhav, Amol R.,Thombal, Raju S.,Nigam, Preeti,Jadhav, Vrushali H.
, p. 5235 - 5237 (2015/08/19)
Synthesis of (±) debenzoyl analogs of norsampsones 1 and 2 is reported starting from commercially available 1,3-cyclohexadione in six steps with overall yields of 37% and 36%, respectively. Compounds 1 and 2 were tested for their anticancer activity and showed moderate anticancer activity against HeLa cell lines.
Total synthesis of (±)-garsubellin A
Kuramochi, Akiyoshi,Usuda, Hiroyuki,Yamatsugu, Kenzo,Kanai, Motomu,Shibasaki, Masakatsu
, p. 14200 - 14201 (2007/10/03)
The first total synthesis of garsubellin A, a neurotrophic compound with potent choline acetyltransferase-inducing activity, is described. Keys for success were (1) stereoselective intermolecular aldol reaction at the C-4 position with acetaldehyde, (2) stereoelective Claisen rearrangement to introduce an allyl group to the most sterically crowded position at C-6, (3) ring-closing metathesis to construct the B-ring, and (4) Wacker-type oxidative C-ring formation. This synthetic route can be extended to an asymmetric synthesis of garsubellin A using the Koga catalytic enantioselective alkylation, which produced enantioenriched α-prenyl cyclohexenone with excellent enantioselectivity (95% ee). Copyright
Progress toward the Synthesis of garsubellin A and related phloroglucins: the direct diastereoselective synthesis of the bicyclo[3.3.1]nonane core.
Spessard, Sarah J,Stoltz, Brian M
, p. 1943 - 1946 (2007/10/03)
[reaction: see text] A highly diastereoselective single-step cyclization reaction provides access to the bicyclo[3.3.1]nonane core of the polyprenylated phloroglucin natural product garsubellin A. Further elaboration to a more functionalized analogue involves a sequential Claisen rearrangement/Grubbs olefin cross-metathesis strategy. Additionally, this strategy was extended to the preparation of the bis-quaternary carbon array found at the bridgehead positions of the phloroglucin natural products.
