Clostebol acetate

The title compound, C21H29ClO3 [systematic name (8R,9S,10R,13S,14S,17S)-4-chloro-3-oxoandrost-4-en-17β-yl acetate], is a 4-chloro derivative of testosterone, used as an anabolic androgenic agent or applied topically in ophthalmological and dermatological treatments. The absolute configurations at positions 8, 9, 10, 13, 14 and 17 were established by refinement of the Flack parameter as R, S, R, S, S, and S, respectively. Rings B and C of the steroid ring system adopt chair conformations, ring A has a half-chair conformation, while ring D is in a C13 envelope conformation. Ring B and C, and C and D are trans fused. In the crystal, molecules are linked by a weak C—H⋯O interaction

Inclusion complexes of β-cyclodextrin with tricyclic drugs: an X-ray diffraction, NMR and molecular dynamics study

Tricyclic fused-ring cyclobenzaprine (1) and amitriptyline (2) form 1:1 inclusion complexes with β-cyclodextrin (β-CD) in the solid state and in water solution. Rotating frame NOE experiments (ROESY) showed the same geometry of inclusion for both 1/β-CD and 2/β-CD complexes, with the aromatic ring system entering the cavity from the large rim of the cyclodextrin and the alkylammonium chain protruding out of the cavity and facing the secondary OH rim. These features matched those found in the molecular dynamics (MD) simulations in solution and in the solid state from single-crystal X-ray diffraction of 1/β-CD and 2/β-CD complexes. The latter complex was found in a single conformation in the solid state, whilst the MD simulations in explicit water reproduced the conformational transitions observed experimentally for the free molecule

Calcium acamprosate: a triclinic polymorph

The title compound, poly[bis­(μ3-4-acetamido­propane­sulfon­ato)­calcium], [Ca(C5H10NO4S)2]n, is a triclinic polymorph of the previously reported monoclinic structure [Toffoli et al. (1988 ▶). Acta Cryst. C44, 1493–1494]. The triclinic modification was found to have an all-trans configuration of the acetamido­propane chain, in contrast with the monoclinic polymorph which shows an angle of 74.66 (8)° between the S—C—C—C chain plane and that of the amide group. The Ca2+ cation is situated on an inversion centre and is hexa­coordinated by six O atoms belonging to different anions in a distorted octa­hedral geometry. This arrangement leads to a layered structure parallel to (011). The layers are held together by N—H⋯O hydrogen bonds and by short C—H⋯O inter­actions, both involving the sulfonate O atoms not coordinated to the Ca2+ cations. The structure was determined from a crystal twinned by non-merohedry [twin law (00, 00, −0.335 −0.85 1), with a fractional contribution of the minor twin domain of 46.7 (1)%]

Trihexyphenidyl hydro­chloride: a powder diffraction study

In the cation of the title compound [systematic name: 1-(3-cyclo­hexyl-3-hy­droxy-3-phenyl­prop­yl)piperidinium chloride], C20H32NO+·Cl−, the cyclo­hexyl and piperidine rings are in chair conformations. In the crystal structure, cations and anions are linked into chains along the c-axis direction via O—H⋯Cl and N—H⋯Cl hydrogen bonds. Weak inter­molecular C—H⋯Cl inter­actions link further these chains into layers parallel to the bc plane. The salt, obtained from a racemic solution, was found to crystallize in the chiral P21212 space group, indicating that, in the absence of any evident chirality-inducing process, the polycrystalline powders consist of an equivalent mixture of R and S enanti­omers, forming a racemic conglomerate

Crystal structure of methyl-2-hydroxy-2-phenyl-3-(4-bromophenyl)-3- phenylamino-propanoate, C22H20BrNO3

Abstract C22H20BrNO3, monoclinic, P121/c1 (no. 14), a = 17.643(1) Å, b = 5.935(1) Å, c = 18.782(1) Å, β = 90.13(1)°, V = 1966.7 Å3, Z = 4, Rgt(F) = 0.041, wRref(F2) = 0.117, T = 293 K.</jats:p

Polymorph of Atomoxetine Hydrochloride in Cristalline Form

Preparazione e caratterizzazione di un polimorfo del principio attivo farmaceutico atomoxitina HCl

Losartan potassium polymorphs and process for the preparation thereof

Preparazione e caratterizzazione di polimorfi del principio attivo farmaceutico losartan potassio