Two drimane lactones, valdiviolide and 11-epivaldiviolide, in the form of a 1:1 cocrystal obtained from Drimys winteri extracts

A cocrystal, obtained from Drimys winteri, is composed of two isomeric drimane sesquiterpene lactones, namely valdiviolide and 11-epivaldiviolide, neither of which has been reported in the crystal form. Both diastereoisomers present three chiral centres at sites 5, 10 and 11, with an SSR sequence in (Ia) and an SSS sequence in (Ib).

The structure of {[Co(pht)(bpy)(H₂O)]·3H₂O}_n (pht is phthalate and bpy is 4,4′-bi­pyridine) and the role of solvent water clusters in structure stability

In a two-dimensional cobalt(II) coordination polymer of benzene-1,2-di­carboxyl­ate and 4,4′-bi­pyridine, inter­planar cohesion is achieved via oligomeric solvent water clusters.

Two nickel(II) bis­[(pyridin-2-yl)meth­yl]amine complexes with homophthalic and benzene-1,2,4,5-tetra­carb­oxy­lic acids

Two new Ni^II complexes are presented, i.e. a one-dimensional polymeric complex incorporating homophthalate, where the anion acts as the bridging ligand, and a complex incorporating benzene-1,2,4,5-tetra­carboxyl­ate, with two independent Ni centres in different environments, one of them a centrosymmetric 4- dinuclear complex and the other a 2+ mononuclear unit, appearing in a 1:2 ratio. The supra­molecular structure is supported by a profuse hydrogen-bonding network.

An ethanol-solvated centrosymmetric dimer of bismuth(III) and thiosaccharinate resulting from `semicoordination' contacts

In an ethanol-solvated centrosymmetric dimer of bismuth(III) and thiosaccharinate, the Bi³⁺ cation is coordinated by three thio­saccharinate ligands, all of them acting as bidentate chelates through the N and exocyclic S atoms (in a [kappa]²N,S mode). Centrosymmetric dimers result from the association of molecules via [pi]-[pi] interactions.

On substituted pyrazole derivatives. I. 3-Methyl-4-[(Z)-2-(4-methyl­phenyl)hydrazin-1-yl­idene]-1-(3-nitro­phenyl)-1H-pyrazol-5(4H)-one and 3-methyl-4-[(Z)-2-(4-methyl­phenyl)hydrazin-1-yl­idene]-1-[4-(tri­fluoro­methyl)phenyl]-1H-pyrazol-5(4H)-one

The title substituted pyrazolone compounds, one of them presenting two mol­ecules in the asymmetric unit, differ in the substituents on two terminal benzene rings. The three-dimensional supra­molecular structure is achieved in both cases via a number of C-H...O, C-H...[pi] and [pi]-[pi] weak inter­actions, linking the mol­ecules into more or less compact supra­molecular structures.

The topotactic dehydration of monoclinic {[Co(pht)(bpy)(H₂O)₂]·2H₂O}_n into ortho­rhom­bic [Co(pht)(bpy)(H₂O)₂]_n (pht is phthalate and bpy is 4,4'-bi­pyridine)

{[Co(pht)(bpy)(H₂O)₂]·2H₂O}_n (P2/n) single crystals (where pht is phthalate and bpy is 4,4'-bi­pyridine) dehydrate in a topotactic fashion into an anhydrate formulated as [Co(pht)(bpy)(H₂O)₂]_n, which organizes in the ortho­rhom­bic system (Pmn2₁) in a disordered fashion, where two mirror-related 0.50:0.50 occupancy two-dimensional planar substructures are mirrored in a plane perpendicular to [100]. These two-dimensional substructures are also present in the parent hydrate, and have been found in topologically related structures with different anions and cations.

Dendocarbin A: a sesquiterpene lactone from Drimys winteri

Natural dendocarbin A is a sesquiterpene lactone isolated from Drimys winteri. X-ray crystal structure analysis confirmed the S/R character of the chiral centres at C-5/C-10 and C-9/C-11, respectively. The α-OH group at C-11 was found to be involved in inter­molecular hydrogen bonding, defining chains along the <100> 2₁ screw axis.

Hobartine: a tetra­cyclic indole alkaloid extracted from Aristotelia chilensis (maqui)

In the crystal structure of the natural compound hobartine, a tetra­cyclic alkaloid isolated from Aristotelia chilensis, the supra­molecular structure in strongly related to the twofold screw axis, around which isolated chains build up, inter­nally linked by an N—H...N hydrogen bond which is the only significant inter­molecular inter­action present in the structure.