The preparation, characterization, structure and dissolution analysis of apremilast solvatomorphs

The ability of apremilast (AP) to form solvates has been investigated and three solvatomorphs of AP, namely, with ethyl acetate, toluene and di­chloro­methane, were obtained. The three AP solvatomorphs were characterized and dissolution analyses were performed to study the dissolution rates of different AP solvatomorph tablets in vitro and to make comparisons with commercial apremilast tablets.

Two new isostructural mercury(II) complexes involving the N-heterocyclic 1-[(benzotriazol-1-yl)meth­yl]-1H-1,3-imidazole ligand: syntheses, structures and properties

Two new isostructural mercury(II) halide complexes based on 1-[(benzotriazol-1-yl)meth­yl]-1H-1,3-imidazole (bmi) have been prepared and structurally characterized. Both complexes exhibit a mononuclear structure, in which the bmi ligands coordinate to Hg^II ions in monodentate modes.

Crystal structure of 5,6-bis­(9H-carbazol-9-yl)benzo[c][1,2,5]thia­diazole: distortion from a hypothetical higher-symmetry structure

The crystal structures of 5,6-bis­(9H-carbazol-9-yl)benzo[c][1,2,5]thia­diazole (DCBT) and its hydrate were investigated using single-crystal X-ray analysis. The analysis of the crystal packing of DCBT revealed that the experimental triclinic structure could be described as a distortion from a hypothetical higher-symmetry monoclinic structure. The quantum chemical calculations of two possible monoclinic structures showed that the proposed structures are higher in energy by 5.4 and 10.1 kcal mol⁻¹.

Unusual 4-arsonoanilinium cationic species in the hydro­chloride salt of (4-amino­phenyl)­arsonic acid and formed in the reaction of the acid with copper(II) sulfate, copper(II) chloride and cadmium chloride

The structure of the hydro­chloride salt of p-arsanilic acid is reported, (I), together with the products from its reaction with copper(II) sulfate, (II), copper(II) chloride, (III), or cadmium chloride, (IV), all featuring the unusual protonated 4-arsonoanilinium species, viz. in (II), along with the [Cu(H₂O)₆]²⁺ species in a 'double' salt, and as counter-cation to [CuCl₄]²⁻ or [CdCl₄]²⁻ in the coordination polymeric sheet structures of isotypic (III) and (IV), respectively.

The influence of P/As substitution in the melilite-like Na₂Co(P_2–xAs_x)O₇ (x = 0.40 and 0.93) solid solutions

Crystal structures of the solid solutions Na₂CoP_1.60As_0.40O₇ and Na₂CoP_1.07As_0.93O₇ have been determined and investigated by BVS (bond valence sum) and CHARDI (charge distribution) validation tools. The BVS model also allowed simulation of the sodium conduction pathways in the studied structural type.

Li₉Al₄Sn₅ as a new ordered superstructure of the Li₁₃Sn₅ type

The crystal structure of the trigonal ternary stannide Li₉Al₄Sn₅ has been determined by the single-crystal method. Li₉Al₄Sn₅ is a new ordered superstructure of the Li₁₃Sn₅ type and represents the stucture family in which the parent structure belongs to the W-type.

Weak hydrogen bonding and fluorous inter­actions in the chloride and bromide salts of 4-[(2,2,3,3-tetra­fluoro­prop­oxy)meth­yl]pyridinium

The halide anions in 4-[(2,2,3,3-tetra­fluoro­prop­oxy)meth­yl]pyridinium chloride and bromide accept four hydrogen bonds from N—H, ortho-C—H and CF₂—H groups. Two cations and two anions form a centrosymmetric dimeric building block, utilizing complimentary N—H⋯X⋯H—Csp³ connections. These dimers are further crosslinked, utilizing another complimentary Csp²—H⋯X⋯H—Csp² connection.

Synthesis and characterization of a novel long-alkyl-chain ester-substituted benzimidazole gelator and its octan-1-ol solvate

The synthesis, gelation and aggregation properties of methyl 8-[4-(1H-benzimidazol-2-yl)phen­oxy]octa­noate and the crystal structure of its octan-1-ol solvate are reported. A four-mol­ecule hydrogen-bonded motif consisting of two benzimidazole mol­ecules and two octan-1-ol mol­ecules is observed in the solid state.

Synthesis and structures of photoactive manganese–carbonyl complexes derived from 2-(pyridin-2-yl)-1,3-benzo­thia­zole and 2-(quinolin-2-yl)-1,3-benzo­thia­zole

Two photoactive Mn^I–carbonyl complexes have been synthesized and their crystal structures are reported. These complexes can be utilized as trackable CO-releasing mol­ecules within biological milieu.

A World From Dust. How the Periodic Table Shaped Life