Zn3(C6H14N2)3[B6P12O39(OH)12] · (C6H14N2)[HPO4]: A Chiral Borophosphate – Triethylenediammonium Hydrogenphosphate Composite

A novel borophosphate, Zn₃(C₆H₁₄N₂)₃[B₆P₁₂O₃₉(OH)₁₂] · (C₆H₁₄N₂)[HPO₄] has been synthesised under mild hydrothermal conditions at T = 165 °C. The chiral crystal structure was determined by single crystal X‐ray diffraction data (trigonal, R3 (no. 146), Z = 3, a = 2089.55(4) pm, c = 1237.03(4) pm, V = 4677.5(2) · 10⁶ pm³, R₁ = 0.066, wR₂ = 0.164 for 5100 observed reflections). The title compound can be considered as an ordered composite of the two different and neutral structures which fit into each other: An open framework of composition Zn₃(C₆H₁₄N₂)₃[B₆P₁₂O₃₉(OH)₁₂] and columns of composition (C₆H₁₄N₂)[HPO₄]. The framework structure is formed by mixed octahedral‐tetrahedral secondary building units, in a three‐dimensional arrangement reflecting a hierarchical derivative of the NbO structure type. The underlying NbO topology is illustrated with the help of Periodic Nodal Surfaces. The composite nature of the compound is resolved in the spatial segregation of two frameworks with a separating surface.     

ZSM-5 zeolite single crystals with b-axis-aligned mesoporous channels as an efficient catalyst for conversion of bulky organic molecules

The relatively small and sole micropores in zeolite catalysts strongly influence the mass transfer and catalytic conversion of bulky molecules. We report here aluminosilicate zeolite ZSM-5 single crystals with b-axis-aligned mesopores, synthesized using a designed cationicamphiphilic copolymer as a mesoscale template. This sample exhibits excellent hydrothermal stability. The orientation of the mesopores was confirmed by scanning and transmission electron microscopy. More importantly, the b-axis-aligned mesoporous ZSM-5 shows much higher catalytic activities for bulky substrate conversion than conventional ZSM-5 and ZSM-5 with randomly oriented mesopores. The combination of good hydrothermal stability with high activities is important for design of novel zeolite catalysts. The b-axis-aligned mesoporous ZSM-5 reported here shows great potential for industrial applications.     

Relaxation of the rigid backbone of an oligoamide-foldamer-based α-helix mimetic: identification of potent Bcl-xL inhibitors

By conducting a structure-activity relationship study of the backbone of a series of oligoamide-foldamer-based α-helix mimetics of the Bak BH3 helix, we have identified especially potent inhibitors of Bcl-x(L). The most potent compound has a K(i) value of 94 nM in vitro, and single-digit micromolar IC(50) values against the proliferation of several Bcl-x(L)-overexpressing cancer cell lines.     

The ionic distribution in Mn2+ and Zn2+ β″-alumina

The ionic distributions in Mn²⁺ and Zn²⁺ β″-alumina (idealized formula: $\text{X}{}_{\mathrm{<mtext>5</mtext><mtext>6</mtext>}}\text{Mg}{}_{\mathrm{<mtext>2</mtext><mtext>3</mtext>}}\text{Al}{}_{\mathrm{<mtext>31</mtext><mtext>3</mtext>}}\text{O}{}_{17}\text{;}\text{X}\text{=}\text{Mn}\text{and}\text{Zn}\text{)}$ at 296 K are reported from single-crystal X-ray diffraction studies. Mn²⁺ β″-alumina exhibits the shortest c-axis found so far in any divalent β″-alumina: 33.141(3) Å;Zn²⁺ β″-alumina, which involves the smallest divalent ion studied in the frame-work, has a considerably longer c-axis: 33.517(3) Å. Both compounds show clear evidence of short-range correlation effects in the X²⁺ ion arrangement by way of departures from the centrosymmetric space-group $\text{R}\text{3}\text{m}$ of the β″-skeleton. Both 6c end-sites and 9d mO-sites ($\text{R}\text{3}\text{m}$ notation) are occupied for both ion-types, a significantly larger occupation (60% compared to 28% of the total) lying at or near the 9d mid-oxygen sites in Mn²⁺ β″-alumina compared to Zn²⁺ β″-alumina. Disorder is also found in the column-oxygen O(5) in both cases; the O(5) displacement from the 3b site in Mn²⁺ β″-alumina (0.59 Å) is the largest found in any divalent β″-alumina. The formula-unit/cell-layer, deduced on the basis of the amounts of X²⁺ ions refined, and assuming charge compensation through Mg substitution alone, are: Mn_0.79Mg_0.57Al_10.43O₁₇ and Zn_0.87Mg_0.74Al_10.26O₁₇.