Fifteen unreported compounds in Anemarrhena asphodeloides, iriflophene (3), hostaplantagineoside C (7), tuberoside G (8), spicatoside B (9), platycodin D (14), platycoside A (15), platycodin D2 (16), polygalacin D2 (17), platycodin D3 (18), isovitexin (20), vitexin (21), 3,4-dihydroxyallylbenzene-3-O-α-l-rhamnopyranosyl(1→6)-β-d-glucopyranoside (22), iryptophan (24), adenosine (25), α-d-Glucose monoallyl ether (26), together with eleven known compounds (1, 2, 4–6, 10–13, 19 and 23), were isolated from the rhizomes of Anemarrhena asphodeloides. The chemical structures of these compounds were characterized using HRMS and NMR. The anti-inflammatory activities of the compounds were evaluated by investigating their ability to inhibit LPS-induced NO production in N9 microglial cells. Timosaponin BIII (TBIII) and trans-hinokiresinol (t-HL) exhibited significant inhibitory effects on the NO production in a dose-dependent manner with IC50 values of 11.91 and 39.08 μM, respectively. Immunoblotting demonstrated that TBIII and t-HL suppressed NO production by inhibiting the expressions of iNOS in LPS-stimulated N9 microglial cells. Further results revealed that pretreatment of N9 microglial cells with TBIII and t-HL attenuated the LPS-induced expression tumor necrosis factor (TNF)-α and interleukin-6 (IL-6) at mRNAs and protein levels. Moreover, the activation of nuclear factor-κB (NF-κB) and phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathways were inhibited by TBIII and t-HL, respectively. Our findings indicate that the therapeutic implication of TBIII and t-HL for neurogenerative disease associated with neuroinflammation.

Novel chiral ionic liquid stationary phases based on chiral imidazolium were prepared. The ionic liquid chiral selector was synthesized by ring opening of cyclohexene oxide with imidazole or 5,6-dimethylbenzimidazole, and then chemically modified by different substitute groups. Chiral stationary phases were prepared by bonding to the surface of silica sphere through thioene "click" reaction. Their enantioselective separations of chiral acids were evaluated by high-performance liquid chromatography. The retention of acid sample was related to the counterion concentration and showed a typical ion exchange process. The chiral separation abilities of chiral stationary phases were greatly influenced by the substituent group on the chiral selector as well as the mobile phase, which indicated that, besides ion exchange, other interactions such as steric hindrance, π-π interaction, and hydrogen bonding are important for the enantioselectivity. In this report, the influence of bulk solvent components, the effects of varying concentration, and the type of the counterion as well as the proportion of acid and basic additives were investigated in detail.

A new one-pot, three component reaction involving the use of Julia reagent, aldehyde, and sodium azide was developed for the efficient synthesis of N-unsubstituted 1,2,3-triazoles. This reaction could be carried out under mild reaction conditions without any precaution, and broad scope of substrates, both respect to Julia reagents and aldehydes, could be applied in this reaction system in generation of a small library of title compounds.

6-(4-Aminophenyl)-5-methyl-4,5-dihydro-3(2H)-pyridazinone is a key synthetic intermediate for cardiotonic agent levosimendan. Very few studies address the use of chiral stationary phases in chromatography for the enantioseparation of this intermediate. This study presents two efficient preparative methods for the isolation of (R)(−)-6-(4-aminophenyl)-5-methyl-4,5-dihydro-3(2H)-pyridazinone in polar organic solvent chromatography and supercritical fluid chromatography using polysaccharide-based chiral stationary phases and volatile organic mobile phases without additives in isocratic mode. Under optimum conditions, Chiralcel OJ column showed the best performance (α = 1.71, Rs = 5.47) in polar organic solvent chromatography, while Chiralpak AS column exhibited remarkable separations (α = 1.81 and Rs = 6.51) in supercritical fluid chromatography with an opposite enantiomer elution order. Considering the sample solubility, runtime and solvent cost, the preparations were carried out on Chiralcel OJ column and Chiralpak AS column (250 × 20 mm i.d.; 10 μm) in polar organic mode and supercritical fluid chromatography mode with methanol and CO 2 /methanol as mobile phases, respectively. By utilizing the advantages of chromatographic techniques and polysaccharide-based chiral stationary phases, this work provides two methods for the fast and economic preparation of (R)(−)-6-(4-aminophenyl)-5-methyl-4,5-dihydro-3(2H)-pyridazinone, which are suitable for the pharmaceutical industry. K E Y W O R D S chiral separation, enantiomers, levosimendan, polar organic solvent chromatography, supercritical fluid chromatography 2482

To improve the chiral recognition capability of a cinchona alkaloid crown ether chiral stationary phase, the crown ether moiety was modified by the chiral group of (1S, 2S)-2-aminocyclohexyl phenylcarbamate. Both quinine and quinidine-based stationary phases were evaluated by chiral acids, chiral primary amines and amino acids. The quinine/quinidine and crown ether provided ion-exchange sites and complex interaction site for carboxyl group and primary amine group in amino acids, respectively, which were necessary for the chiral discrimination of amino acid enantiomers. The introduction of the chiral group greatly improved the chiral recognition for chiral primary amines. The structure of crown ether moiety was proved to play a dominant role in the chiral recognitions for chiral primary amines and amino acids.

Ketorolac has been widely applied in clinical medicine for its antipyretic, analgesic and anti‐inflammatory pharmacological activity. Research showed that the analgesic effect of the S enantiomer is 230 times stronger than that of the R enantiomer. Getting the high‐purity S enantiomer of Ketorolac has profound significance but still remains a challenging topic. In this work, the separation of the R and S enantiomers of Ketorolac was investigated on polysaccharide‐based chiral stationary phases. Chiralcel AD‐H, OD‐H, OJ‐H and AS‐H columns were evaluated using polar organic and normal phase mode, respectively, in which the OJ‐H column showed the best performance with high selectivity and resolution for Ketorolac with α = 2.43 and RS = 9.04 by using methanol/formic acid (100:0.1, v/v) as the mobile phase. The influences of acid additive, composition of mobile phase and temperature were examined. The coating amount of cellulose tris‐(4‐methylbenzoate) has significant influence on the sample loadability. The high loadability of chiral stationary phases coated with 40% of cellulose tris‐(4‐methylbenzoate) allows preparative separation up to 16 mg on an analytical column of 250 × 4.6 mm id in a single run for Ketoroac using methanol/formic acid (100:0.1, v/v) as mobile phase, which shows a potential application in industrial preparation.

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Novel chiral selectors based on 3,5‐dimethyl phenylcarbamoylated β‐cyclodextrin connecting quinine (QN) or quinidine (QD) moiety were synthesized and immobilized on silica gel. Their chromatographic performances were investigated by comparing to the 3,5‐dimethyl phenylcarbamoylated β‐cyclodextrin (β‐CD) chiral stationary phase (CSP) and 9‐O‐(tert‐butylcarbamoyl)‐QN‐based CSP (QN‐AX). Fmoc‐protected amino acids, chiral drug cloprostenol (which has been successfully employed in veterinary medicine), and neutral chiral analytes were evaluated on CSPs, and the results showed that the novel CSPs characterized as both enantioseparation capabilities of CD‐based CSP and QN/QD‐based CSPs have broader application range than β‐CD‐based CSP or QN/QD‐based CSPs. It was found that QN/QD moieties play a dominant role in the overall enantioseparation process of Fmoc‐amino acids accompanied by the synergistic effect of β‐CD moiety, which lead to the different enantioseparation of β‐CD‐QN‐based CSP and β‐CD‐QD‐based CSP. Furthermore, new CSPs retain extraordinary enantioseparation of cyclodextrin‐based CSP for some neutral analytes on normal phase and even exhibit better enantioseparation than the corresponding β‐CD‐based CSP for certain samples.