Two new natural 10-membered macrolides (1, 2) and one chromene-4,5-dione derivative (3), named stagonolides J and K and stagochromene A, respectively, were isolated from the phytopathogenic fungus Stagonospora cirsii S-47, together with two known compounds, stagonolide A (4) and herbarumin I (5). Stagonolides J and K and stagochromene A were characterized as (5E,7R*,8S*,9R*)-7,8-dihydroxy-9-propyl-5-nonen-9-olide, (5E,7R,9S)-7-hydroxy-9-propyl-5-nonen-9-olide, and (2R*,3R*)-3-hydroxy-2-propyltetrahydro-2H-chromene-4,5­(3H,4aH)-dione, respectively, by spectroscopic (mostly by NMR and ESIMS) data. Compounds 1–5 showed different rates of phytotoxic activity on punctured leaf discs of Sonchus arvensis. The antimicrobial, cytotoxic, and antiprotozoal activity of isolated compounds was also evaluated. Based on our data, stagonolide K and herbarumin I can be proposed as a potential scaffold for the development of a new natural herbicide and estimated as possible selection/quality markers of a bioherbicide based on S. cirsii, while stagonolide A can be considered as a mycotoxin.

The crystal structure of quintinite-2H-3c, [Mg4Al2(OH)12](CO3)(H2O)3, from the Kovdor alkaline massif, Kola peninsula, Russia, was solved by direct methods and refined to an agreement index (R1) of 0.055 for 484 unique reflections with |Fo| ≥ 4σF. The mineral is rhombohedral, R32, a = 5.2745(7), c = 45.36(1) Å. The diffraction pattern of the crystal has strong and sharp Bragg reflections having h–k = 3n and l = 3n and lines of weak superstructure reflections extended parallel to c* and centred at h–k ≠ 3n. The structure contains six layers within the unit cell with the layer stacking sequence of …AC=CA=AC=CA=AC=CA… The Mg and Al atoms are ordered in metal hydroxide layers to form a honeycomb superstructure. The full superstructure is formed by the combination of two-layer stacking sequence and Mg-Al ordering. This is the first time that a long-range superstructure in carbonate-bearing layered double hydroxide (LDH) has been observed. Taking into account Mg-Al ordering, the unique layer sequence can be written as …=Ab1C=Cb1A=Ab2C=Cb2A=Ab3C=Cb3A=… The use of an additional suffix is proposed in order to distinguish between LDH polytypes having the same general stacking sequence but with different c parameters compared with the ‘standard’ polytype. According to this notation, the quintinite studied here can be described as quintinite-2H-3c or quintinite-2H-3c[6R], indicating the real symmetry.

Quintinite-1M, [Mg4Al2(OH)12](CO3)(H2O)3, is the first monoclinic representative of both synthetic and natural layered double hydroxides (LDHs) based on octahedrally coordinated di- and trivalent metal cations. It occurs in hydrothermal veins in the Kovdor alkaline massif, Kola peninsula, Russia. The structure was solved by direct methods and refined to R1 = 0.031 on the basis of 304 unique reflections. It is monoclinic, space group C2/m, a = 5.266(2), b = 9.114(2), c = 7.766(3) Å, β = 103.17(3)°, V = 362.9(2) Å3. The diffraction pattern of quintinite-1M contains sharp reflections corresponding to the layer stacking sequence characteristic of the 3R rhombohedral polytype, and rows of weak superlattice reflections superimposed upon a background of streaks of modulated diffuse intensity parallel to c*. These superlattice reflections indicate the formation of a 2-D superstructure due to Mg-Al ordering. The structure consists of ordered metal hydroxide layers and a disordered interlayer. As the unit cell contains exactly one layer, the polytype nomenclature dictates that the mineral be called quintinite-1M. The complete layer stacking sequence can be described as …=Ac1B=Ba1C=Cb1A=… Quintinite-1M is isostructural with the monoclinic polytype of [Li2Al4(OH)12](CO3)(H2O)3.

Reactions of (di-)bromo-substituted CF3-allyl alcohols with/without arenes with TfOH lead to CF3-alkenes or CF3-indenes.

The crystal structure of vigrishinite, an epistolite-group heterophyllosilicate with essential Zn, has been reinvestigated; the ideal end-member formula is revised to Zn 2 Ti 4-x (Si 2 O 7) 2 O 2 (OH,F,O) 2 (H 2 O,OH,&) 4 with x,1. Structure models of Zn-exchanged forms of murmanite after 5 and 24 hour experiments with 1N ZnSO 4 solution at 90 C have been obtained from single-crystal X-ray diffraction data. The structural formulae are [B1] Ca 0.04 {Na 1.22 (Ti 1.19 Mn 0.60 Nb 0.21)}{ [A1,A2] Zn 1.03 (Ti 1.64 Nb 0.36)[Si 2 O 7 ] 2 }O 2 (O,OH) 2 (H 2 O) 4 for vigrishinite and {Na 1.14 (Ti 1.45 Mn 0.50 Nb 0.05)}{ [A1] Ca 0.77 [A2] Zn 0.13 (Ti 1.85 Nb 0.15)[Si 2 O 7 ] 2 }O 2 (OH,O) 2 (H 2 O) 4 and [B1] Zn 0.15 [B2] Ca 0.18 {Na 1.06 (Ti 1.32 Mn 0.60 Nb 0.08)}{ [A1] Zn 0.70 [A2] Ca 0.12 (Ti 1.74 Nb 0.26)[Si 2 O 7 ] 2 }O 2 (OH,O) 2 (H 2 O) 4 for the 5 and 24 hour Zn-exchanged forms of murmanite, respectively (braces give successively the contents of the octahedral O and heteropolyhedral H sheets). The triclinic (PÀ1) unit-cell parameters are respectively:

Single crystals of Cs2BiAgBr6 lead-free perovskite were grown by crystallization from supersaturated solution. According to characterization by XRD and EBSD methods the double perovskite single crystal are of the cubic Fm-3m symmetry with the lattice constant a = 11.20 Å. DFT predictions based on the single crystal X-ray diffraction analysis reveal that the material is an indirect band gap semiconductor. Low temperature (1.4 K) photoluminescence spectra demonstrate three broadened bands that correspond to two lowest computed indirect and one direct band-to-band transitions.

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The fungus, Alternaria sonchi is considered to be a potential agent for the biocontrol of perennial sowthistle (Sonchus arvensis). A new chlorinated xanthone, methyl 8-hydroxy-3-methyl-4-chloro-9-oxo-9H-xanthene-1-carboxylate (1) and a new benzophenone derivative, 5-chloromoniliphenone (2), were isolated together with eleven structurally related compounds (3–13) from the solid culture of the fungus, which is used for the production of bioherbicidal inoculum of A. sonchi. Their structures were determined by spectroscopic (mostly by NMR and MS) methods. Alternethanoxins A and B, which were reported in A. sonchi earlier, were re-identified as moniliphenone and pinselin, respectively. The isolated compounds were tested for phytotoxic, antimicrobial, insecticidal, cytotoxic and esterase-inhibition activities. They did not demonstrate high phytotoxicity (lesions up to 2.5 mm in diameter/length at a concentration of 2 mg/mL) when tested on leaf disks/segments of perennial sowthistle (Sonchus arvensis) and couch grass (Elytrigia repens). They did not possess acute toxicity to Paramecium caudatum, and showed moderate to low cytotoxicity (IC50 > 25 µg/mL) for U937 and K562 tumor cell lines. However, chloromonilicin and methyl 3,8-dihydroxy-6-methyl-4-chloro-9-oxo-9H-xanthene-1-carboxylate (4) were shown to have antimicrobial properties with MIC 0.5–5 µg/disc. Compound 4 and chloromonilinic acid B were found to have contact insecticidal activity to wheat aphid (Schizaphis graminum) at 1 mg/mL. Compounds 2 and methyl 3,8-dihydroxy-6-methyl-9-oxo-9H-xanthene-1-carboxylate displayed selective carboxylesterase inhibition activity at concentration of 100 µg/mL. Therefore, the waste solid substrate for production of A. sonchi spores can be re-utilized for the isolation of a number of valuable natural products.