Proton-Conductive Coordination Polymers Based on Diphenylsulfone-3,3'-disulfo-4,4'-dicarboxylate with Well-Defined Hydrogen Bonding Networks.

The diphenylsulfone-3,3'-disulfo-4,4'-dicarboxylic acid (H4-DPSDSDC) ligand and its coordination polymers, [K2Zn(C14H6S3O12)(H2O)4]n (1) and {[Cu3(µ3-OH)2(C14H6S3O12)(H2O)3(DMF)]·3(H2O)}n (2) (C14H6S3O12 = diphenylsulfone-3,3'-disulfo-4,4'-dicarboxylate), were synthesized. The Zn(H2O)4 units in 1 are connected by DPSDSDC4- ligands to generate a one-dimensional (1D) chain, which is bridged by K-O bonds associated with bridging water molecules and sulfonate groups to yield a two-dimensional (2D) layer. In 2, the 1D hydroxyl-bridging Cu(II) chains are connected by DPSDSDC4- ligands to give a 2D layer. The 2D layers in 1 and 2 are further connected by interlayered hydrogen bonds to give three-dimensional (3D) frameworks. Compounds 1 and 2 have good conductivities of 1.57 × 10-4 and 5.32 × 10-5 S cm-1, respectively. Continuous well-defined hydrogen bonding networks associated with water molecules, sulfonate groups, and carboxylate groups were observed in compounds 1 and 2. Such hydrogen bonding networks provide hydrophilic domains and effective transfer pathways for protons. Here, we present elegant examples of a precise determination of the pathways for proton transport.

Fluorinated Biphenyldicarboxylate-Based Metal-Organic Framework Exhibiting Efficient Propyne/Propylene Separation.

A novel fluorinated biphenyldicarboxylate ligand of 3,3',5,5'-tetrafluorobiphenyl-4,4'-dicarboxylic acid (H2-TFBPDC) and its terbium metal-organic framework, {[Tb2(TFBPDC)3(H2O)]·4.5DMF·0.5H2O}n (denoted as JXNU-6), were synthesized. JXNU-6 exhibits a three-dimensional (3D) framework built from one-dimensional (1D) terbium carboxylate helical chains bridged by TFBPDC2- linkers. The 3D framework of JXNU-6 features 1D fluorine-lined channels. The gas adsorption experiments show that the activated JXNU-6 (JXNU-6a) displays distinct adsorption behavior for propyne (C3H4) and propylene (C3H6) gases. The effective removal of a trace amount of C3H4 from C3H6 was achieved by JXNU-6a under ambient conditions, which is demonstrated by the column-breakthrough experiments. The modeling studies show that the preferential binding sites for C3H4 are the exposed F atoms on the pore surface in 1D channels. The strong C-H···F hydrogen bonds between C3H4 molecules and F atoms of TFBPDC2- ligands dominate the host-guest interactions, which mainly account for the excellent C3H4/C3H6 separation performance of JXNU-6a. This work provides a strategy for specific recognition toward C3H4 over C3H6 through the C-H···F hydrogen bond associated with the fluorinated organic ligand.

Lanthanide 5,7-Disulfonate-1,4-naphthalenedicarboxylate Frameworks Constructed from Trinuclear and Tetranuclear Lanthanide Carboxylate Clusters: Proton Conduction and Selective Fluorescent Sensing of Fe3.

The novel sulfonate-carboxylate ligand of 5,7-disulfonate-1,4-naphthalenedicarboxylic acid (H4-DSNPDC) was synthesized, and its series of lanthanide compounds {[Ln3(µ2-OH)(DSNPDC)2(H2O)x]·yH2O}n (JXNU-7; Ln = La3+, x = 10. y = 4; Ln = Nd3+, Sm3+ Eu3+, x = 9, y = 2) and {[Ln4(µ3-OH)4(DSNPDC)2(H2O)11]·28H2O}n (JXNU-8; Ln = Eu3+, Gd3+) are presented. JXNU-7 is a three-dimensional structure based on linear trinuclear Ln3 building units, while JXNU-8 has a two-dimensional layer constructed from tetranuclear Ln4(µ3-OH)4 building units. The representative Eu compounds of JXNU-7 and -8 show good proton conductive properties under high humidity. The hydrophilic sulfonate groups pointing to the pores and the water molecules included in the pores mainly contribute to the high proton conductivity for the materials. The presence of one-dimensional infinite hydrogen-bonded networks in channels of JXNU-7(Eu) facilitates a fast and efficient proton transfer, resulting in higher proton conductivity in comparison to that of JXNU-8(Eu). Additionally, JXNU-7(Eu) with a characteristic red emission exhibits a promising potential for selective sensing of Fe3+ ions in aqueous solution. Our work demonstrates the integration of functional organic components (sulfonate groups) and inorganic components (lanthanide centers) in MOFs for the successful preparation of multifunctional MOF materials.

Drug resistance. Population transcriptomics of human malaria parasites reveals the mechanism of artemisinin resistance.

Artemisinin resistance in Plasmodium falciparum threatens global efforts to control and eliminate malaria. Polymorphisms in the kelch domain-carrying protein K13 are associated with artemisinin resistance, but the underlying molecular mechanisms are unknown. We analyzed the in vivo transcriptomes of 1043 P. falciparum isolates from patients with acute malaria and found that artemisinin resistance is associated with increased expression of unfolded protein response (UPR) pathways involving the major PROSC and TRiC chaperone complexes. Artemisinin-resistant parasites also exhibit decelerated progression through the first part of the asexual intraerythrocytic development cycle. These findings suggest that artemisinin-resistant parasites remain in a state of decelerated development at the young ring stage, whereas their up-regulated UPR pathways mitigate protein damage caused by artemisinin. The expression profiles of UPR-related genes also associate with the geographical origin of parasite isolates, further suggesting their role in emerging artemisinin resistance in the Greater Mekong Subregion.