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Oleanolic acid (OA) is a pentacyclic triterpenoid acid of natural abundance in plants which possesses important biological activities. However, its medicinal applications were severely impeded by the poor water solubility and resultant low bioavailability and potency. In this work, studies on solid inclusion complexes of OA with a series of amino-appended β-cyclodextrins (ACDs) were conducted in order to address this issue. These complexes were prepared by suspension method and were well characterized by NMR, SEM, XRD, TG, DSC and Zeta potential measurement. The 2:1 inclusion mode of ACDs/OA complexes was elucidated by elaborate 2D NMR (ROESY). Besides, water solubility of OA was dramatically promoted by inclusion complexation with ACDs. Moreover, in vitro anticancer activities of OA against human cancer cell lines HepG2, HT29 and HCT116 were significantly enhanced after formation of inclusion complexes, while the apoptotic response results indicated their induction of apoptosis of cancer cells. This could provide a novel approach to development of novel pharmaceutical formulations of OA.

The title chromenes are obtained by one-pot three-component reaction of various aldehydes, malononitrile, and dimedone using beta-cyclodextrin as catalyst under mild reaction conditions.

An economic four-step synthesis of 2,6-dimethoxy-1,4-benzoquinone was achieved in 68% overall yield starting from aniline. The reaction sequence involved conversion to 1,3,5-tribromoaniline, deamination, methoxylation, and oxidation. The procedure is operationally simple and amenable to scale-up production.

The MS n spectra of three bimetallic oxovanadium complexes were obtained using an ion trap. The fragmentation pathways were elucidated. Common features and major differences between ESI–QTOF–MS/MS and ESI–IT–MS n spectra were compared. Electron affinities of several radical molecular anions were calculated by DFT and these could be used as an indicator of the ions’ stability.

Scutellarein has been prepared by the hydrolysis of scutellarin with sulfuric acid to provide this biologically important rare flavone in up to > 90% yield and on the 5 g scale in minutes. This pro...

The practical synthetic preparation of glutaric acid has remained a major challenge to date. In the present study, glutaric acid was synthesised by way of one-pot diazoniation/hydrogenation of the readily available L-glutamic acid under aqueous conditions on a gram-scale with good yields. This is the first example of the deamination of the aliphatic primary amine via diazoniation and could afford a practical approach to the production of glutaric acid.

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 0.58, 1.62, and 5.18μmol/L, respectively. In addition, the supposition of better cytotoxicity was further supported by the control experiment of fluorescent cyclodextrin.

Hantzsch 1,4-dihydropyridines were converted to the corresponding pyridines efficiently by sodium chlorite under mild conditions in excellent yields.

The characterization, binding ability and inclusion complexation behavior of the inclusion complexes of norathyriol with β-cyclodextrin (β-CD) and its derivatives such as hydroxypropyl-β-cyclodextrin (HPβCD), sulfobutyl ether β-cyclodextrin (SBEβCD) and mono (6-ethylene-diamino-6-deoxy)-β-cyclodextrin (ENβCD) were investigated in both solution and solid state by means of femtosecond spectroscopy, (1)H and 2D nuclear magnetic resonance, powder X-ray diffraction. The results showed that the aqueous solubility of the complexes was much higher than that of norathyriol. The cytotoxicity of complexes on human colon cancer cell lines HT-29, SW480, Lovo and HCT116 indicated that the antitumor activities of the complexes were better than that of norathyriol. This high antitumor activity, along with the satisfactory aqueous solubility of the complexes, will be potentially useful for their application on cancer chemotherapies.

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 (1.03×10−6 and 1.01×10−6mol/L, respectively), which compared with those of free SCU (7.80×10−5 and 7.70×10−5mol/L, respectively), were lower. The valuable properties of SCU–PR will be potentially useful for its application on human colon cancer chemotherapies.

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. The cytotoxicity of SCU-CD conjugates on human colon cancer cell lines HT-29, SW480, Lovo and HTC116 indicated that the antitumor activities of the conjugates were better than that of scutellarin. This high antitumor activity, along with the satisfactory aqueous solubility and high stability of the conjugates, will be potentially useful for their application on human colon cancer chemotherapies.

The oxidation is mediated by chlorine dioxide, generated in situ, to give the corresponding pyridines in excellent yields.