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The mixed‐metal pillar‐layered metal–organic frameworks of Zn(bdc)(DABCO)0.5, Zn0.5Cu0.5(bdc)(DABCO)0.5 and Cu(bdc)(DABCO)0.5 (bdc = 1,4‐benzenedicarboxylate, DABCO = 1,4‐diazabicyclo[2.2.2]octane) are investigated for their local structures and gas adsorption properties. According to the obtained electron paramagnetic resonance (EPR) spectra, the distorted structures around Cu2+ are proposed to be tetragonally and orthorhombically elongated [CuO4N] with the well fitted high‐order perturbation formulae of the EPR parameters. Due to the doped Cu2+, the adsorption isotherms of industrially relevant gases (CO2, CO, CH4 and N2) and lower alkanes (CH4, C2H6, C3H8, C4H10 and C5H12) are different, especially at different temperatures. By combining the structural properties and adsorption isotherms, a comprehensive study suggests that the ZnDABCO series can be a controllable tool in gas storage and separation. [ABSTRACT FROM AUTHOR]

Two new furostanol saponins ophiopogonins J (1) and K (2) were isolated from the fibrous roots ofOphiopogon japonicus. The structures of1and2were established as (25R)-26-O-[(β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl)]-14-hydroxy-furost-5,20(22)-diene 3-O-[α-l-rhamnopyranosyl-(1 → 2)]-β-d-glucopyranoside (1), and (25R)-26-O-[(β-d-glucopyranosyl-(1 → 2)-β-d-glucopyranosyl)]-furost-5,20(22)-diene 3-O-α-l-rhamnopyranosyl-(1 → 2)[(β-d-xylopyranosyl-(1 → 4)-β-d-glucopyranoside)] (2) on the basis of spectroscopic means including HRESIMS, 1D, and 2D NMR experiments. [ABSTRACT FROM PUBLISHER]

Molecular tools of double or multimeric G-quadruplexes have been given higher requirements on detection sensitivity, thermal stabilization and cell imaging to establish functions of these G-quadruplex aggregates and biological mechanisms as anticancer reagents. Here, two smart berberine-bisquinolinium conjugates (Ber-360A and Ber-PDS) by linking the berberine fluorophore ligand and an established G-quadruplex binder (i.e. bisquinolinium scaffold), have been designed and evaluated their activities and mechanisms for G-quadruplex aggregation. Two conjugates, especially Ber-PDS, are two highly selective, sensitive and fluorescent sensors which can distinguish human telomere double G-quadruplexes from other type G-quadruplexes and ds DNA. These two ligands could be the first example to stack two adjacent G-quadruplex units and fluorescently recognize human telomere double G-quadruplexes. Furthermore, conjugate Ber-PDS could enter the nucleoli and target G-quadruplex DNA through microscopy experiments, and also display strong telomerase inhibition and antitumor activities., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2020. Published by Elsevier B.V.)