Publications by authors named "Xia-Li Liao"

Outlined herein is a novel and scalable synthesis of (-)-vindorosine based on two key transformations. A highly diastereoselective vinylogous Mannich addition of dioxinone-derived lithium dienolates with indolyl N-tert-butanesulfinyl imines has been developed. In addition, an intramolecular Heathcock/aza-Prins cyclization was introduced to construct both the C, and the highly substituted E rings for the synthesis of (-)-vindorosine and related alkaloids.

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Article Synopsis
  • Six new grayanane diterpenoids (neopierisoids G-L) were discovered in Pieris japonica flowers, along with ten known compounds.
  • The structures of the new compounds were determined using advanced techniques like NMR spectroscopy and mass analysis, with absolute configurations established through X-ray diffraction and CD spectrum comparison.
  • The new compounds exhibited significant antifeedant activity against the pest Pieris brassicae, with the study analyzing the relationship between their structures and effectiveness as deterrents.
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A series of novel artesunate-polyrotaxanes (ATS-PRs) with folic acid capped, in which artesunate (ATS) was covalently bound to a cyclodextrin (CD) of the polyrotaxane (PR), were synthesized and were characterized by NMR, XRD, TG and DSC. The cytotoxicities of ATS-PRs on human colon cancer cell lines HT-29, SW480, HTC116 and DLD-1 showed that their antitumor activities were better than that of artesunate (ATS) and dihydroartemisinin (DHA). These ATS-PRs may provide a useful approach to the development of a highly effective drug candidate for the chemotherapy of human colon cancer.

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A novel series of artesunate-β-cyclodextrin (ATS-β-CD) conjugates, in which artesunate (ATS) was coupled covalently to one of the primary hydroxyl groups of β-cyclodextrin (β-CD) through amino bond formation, were synthesized and characterized by (1)H NMR, HRMS, 2D NMR (ROESY), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The results showed that the aqueous solubility of ATS-β-CD conjugates was 26-45 times better than that of free ATS. The cytotoxicity of the ATS-β-CD conjugates was evaluated on human colon cancer cell lines HCT116, LOVO, SW480, and HT-29, and the results indicated that ATS-2NβCD exhibited a very high cytotoxicity against HCT116, LOVO, and HT-29 with IC50 values of 0.

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The safe and effective polyrotaxane-based drug delivery system could potentially increase the antiproliferative activity of antitumor medicine. A novel scutellarin-polyrotaxane (SCU-PR), in which scutellarin (SCU) was covalently bound to one of the hydroxyl groups of polyrotaxane (PR), was synthesized, and its characterization was further investigated by NMR, XRD, TG, DSC. The cytotoxicity of SCU-PR was assessed in vitro using human HCT116 and LOVO cell lines in results that the IC50 values of SCU-PR (1.

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A series of scutellarin-cyclodextrin conjugates (SCU-CD conjugates), in which scutellarin was covalently bound to one of the primary hydroxyl groups of β-CD, were prepared, and their structures were determined using NMR and MS. These conjugates were further characterized by XRD and TG. The results showed that the aqueous solubility of the conjugates was much higher than that of scutellarin, and the conjugates could hardly be hydrolyzed to scutellarin in aqueous solutions.

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16-O-Methyl-cafestol.

Acta Crystallogr Sect E Struct Rep Online

March 2010

THE TITLE COMPOUND [SYSTEMATIC NAME: (3bS,5aS,7R,8R,10aR,10bS)-7-meth-oxy-10b-methyl-3b,4,5,6,7,8,9,10,10a,10b,11,12-dodeca-hydro-5a,8-methano-5aH-cyclo-hepta-l[5,6]naph-tho[2,1-b]furan-7-methanol], C(21)H(30)O(3), was isolated from the beans of Coffea robusta. The mol-ecule contains five fused rings including a furan ring. The two six-membered rings are in chair conformations, but the third six-membered ring and the five-membered aliphatic ring adopt envelope conformations.

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