Aqua­[1,8-bis­(pyridin-2-yl)-3,6-dithia­octane-κ⁴N,S,S′,N′]copper(II) dinitrate acetonitrile monosolvate

In the title compound, [Cu(C₁₆H₂₀N₂S₂)(H₂O)](NO₃)₂·CH₃CN, the Cu^II atom displays a distorted square-pyramidal coordination, in which a water mol­ecule occupies the apical position and the basal plane is formed by two N atoms and two S atoms of a 1,8-bis­(pyridin-2-yl)-3,6-dithia­octane ligand. The crystal packing is stabilized by O—H...O and C—H...O hydrogen bonds.

(7aS)-(–)-Dimeth­yl(1-oxido-3-oxo-5,6,7,7a-tetra­hydro-3H-pyrrolizin-2-yl)sulfonium

In the zwitterionic title compound, C₉H₁₃NO₂S, the pyrrolidine heterocycle adopts an envelope conformation (with the C atom in the 7-position as the flap). The negative charge is delocalized over the two carbonyl groups and the C atom connecting them. The positive charge is located on the S atom. Two inter­molecular C—H...O inter­actions are observed. The molecular geometry at the S atom is trigonal pyramidal.

Tris(5,6-dimethyl-1,10-phenanthroline-κ²N,N′)copper(II) bis­(hexa­fluorido­phosphate) acetonitrile monosolvate

In the title compound, [Cu(C₁₄H₁₂N₂)₃](PF₆)₂·CH₃CN, the [Cu(5,6-dmp)₃]²⁺ cationic complex (5,6-dmp is 5,6-dimethyl-1,10-phenanthroline) is stabilized by two hexa­fluorido­phosphate anions and one acetonitrile solvent mol­ecule. The coordination geometry around the Cu^II atom can be described as distorted elongated octa­hedral with R_out = 2.277 (2) Å, R_in = 2.052 (2) Å and a tetra­gonality of 0.9011, acquiring a `static' stereochemistry. In the supra­molecular network, there are inter­molecular C—H...F and C—H...N inter­actions with R₃³(16), R₂²(7), R₁²(4), R₃³(16) and C₃²(7) motifs that lead to an infinite three-dimensional network.

Diaqua­tris­(nitrato-κ²O,O′){2,2′-[pyridine-2,6-diylbis(methyl­ene­oxy)]dibenzaldehyde-κO¹}dysprosium(III)–2,2′-[pyridine-2,6-diylbis(methyl­ene­oxy)]dibenzaldehyde (1/1)

The title compound, [Dy(NO₃)₃(C₂₁H₁₇NO₄)(H₂O)₂]·C₂₁H₁₇NO₄, may be considered as an organic–metalorganic 1:1 co-crystal, in which the two dialdehyde mol­ecules act as a ligand and as an organic moiety, respectively. The Dy^III atom coordinates nine O atoms from the organic ligand, bidentate nitrate ions and water mol­ecules, approximating a square-face-tricapped trigonal–prismatic geometry. The coordinated dialdehyde is not planar: the uncoordinated oxybenzaldehyde group is twisted by 39.96 (4)° from the rest of the ligand. In contrast, the free organic moiety is almost planar, with an r.m.s. deviation of 0.15 Å. In the crystal, segregated stacks of dialdehyde are formed in the [100] direction. For the complex, the shortest π–π contact is found at 3.781 (2) Å, and for the free ligand, at 3.785 (2) Å. The crystal structure is further stabilized by O—H...O and O—H...N hydrogen bonds in which coordinated water mol­ecules are the donor groups.

Tris[2-(2H-indazol-2-yl)eth­yl]amine

The title tertiary amine, C₂₇H₂₇N₇, a potential tripodal ligand for coordination chemistry, crystallizes with the central N atom located on a threefold axis of a trigonal cell. The gauche conformation of the N(amime)—CH₂—CH₂—N(indazole) chain [torsion angle = −64.2 (2)°] places the pendant 2H-indazole heterocycles surrounding the symmetry axis, affording a claw-like shaped mol­ecule. Two symmetry-related indazole planes in the mol­ecule make an acute angle of 60.39 (4)°. The lone pair of the tertiary N atom is located inside the cavity, and should thus be inactive (as a ligand). In the crystal, neither significant π–π nor C—H...π inter­actions between molecules are found.

(R)-3,3-Diethyl-1-(2-hy­droxy-1-phenyl­eth­yl)piperidin-2-one

In the title compound C₁₇H₂₅NO₂, the piperidin-2-one ring adopts an envelope conformation with the C atom in the 5-position as the flap. The crystal packing is stabilized by inter­molecular O—H...O hydrogen bonds, building a infinite chain along the b-axis direction. C—H...π inter­actions further stabilize the crystal packing.

Diosgenin hemihydrate

Diosgenin [or (22R,25R)-spirost-5-en-3β-ol] is the starting material of the Marker degradation, a cheap semi-synthesis of progesterone, which has been designated as an Inter­national Historic Chemical Landmark. Thus far, a single X-ray structure for diosgenin is known, namely its dimethyl sulfoxide solvate [Zhang et al. (2005). Acta Cryst. E61, o2324–o2325]. We have now determined the structure of the hemihydrate, C₂₇H₄₂O₃·0.5H₂O. The asymmetric unit contains two diosgenin mol­ecules, with quite similar conformations, and one water mol­ecule. Hy­droxy groups in steroids and water mol­ecules form O—H...O hydrogen-bonded R₅⁴(10) ring motifs. Fused edge-sharing R(10) rings form a backbone oriented along [100], which aggregates the diosgenin mol­ecules in the crystal structure.

Diosgenone: a second P2₁ polymorph

Diosgenone [(20S,22R,25R)-spirost-4-en-3-one, C₂₇H₄₀O₃] has been proposed as a new therapeutic alternative for the treatment of malaria. The first X-ray structure report for diosgenone was by Piro et al. [(2002). Z. Naturforsch. Teil C, 57, 947–950] in the space group P2₁ (Z′ = 2). We now report a new polymorph in the same space group, with two mol­ecules in the asymmetric unit. Both mol­ecules have similar conformations, characterized by a skewed envelope A ring, which contains the C=C bond conjugated with the ketone functionality at C3. The dimorphism results from a modification of the relative orientation of the mol­ecules in the asymmetric unit: two independent mol­ecules were arranged anti­parallel in the Piro report, while they are parallel in the present determination.

4,4′-[(2R*,3R*,4R*,5R*)-3,4-Dimethyl­tetra­hydro­furan-2,5-di­yl]diphenol

The title mol­ecule, C₁₈H₂₀O₃, is a furan­oid lignan extracted from the leaves of Larrea tridentata. The relative absolute configuration for the four chiral centers was established, showing that this compound is 4-epi-larreatricin, which has been previously reported in the literature. The mol­ecule displays noncrystallographic C₂ symmetry, with the methyl and phenol substituents alternating above and below the mean plane of the furan ring. The conformation of this ring is described by the pseudorotation phase angle P = 171.3° and the maximum out-of-plane pucker ν_m = 37.7°. These parameters indicate that the furan ring adopts the same conformation as the ribose residues in B-DNA. The packing is dominated by inter­molecular O—H...O hydrogen bonds. The phenol hy­droxy groups form chains in the [110] direction and these chains inter­act via O—H...O(furan) contacts.

(E)-1-(4-Nitro­benzyl­idene)-2,2-diphenyl­hydrazine

The asymmetric unit of the title compound, C₁₉H₁₅N₃O₂, contains two mol­ecules, both of which show an E conformation of the imine bond. The dihedral angles between the phenyl rings in the phenyl­hydrazine groups are 86.09 (6) and 83.41 (5)° in the two mol­ecules. The 4-nitrobenzene rings show torsion angles of 4.4 (2) and 10.9 (2)° from the two C=N—N planes. In the crystal, C—H...π inter­actions and C—H...O hydrogen bonds are observed growing along the a, b and c axes, resulting in a complex supramolecular array.