A monoclinic polymorph of cysteamine hydro­chloride

The title compound (systematic name: 2-mercaptoethan­aminium chloride), C2H8NS+·Cl−, the hydro­chloride salt of cysteamine, in contrast to the previously reported triclinic polymorph [Kim et al. (2002 ▶). Polyhedron, 21, 225–228], crystallized in the monoclinic crystal system. In the crystal, the cysteaminium cations are linked to the chloride anions via one S—H⋯Cl and three N—H⋯Cl hydrogen bonds. Two-dimensional slab-like networks are formed, which are stacked in [100]. This arrangement is similar to that observed in the triclinic polymorph

Dicyclo­hexyl­ammonium hydrogen phenyl­phospho­nate

In the title salt, [(C6H11)2NH2]+·[C6H5PO2(OH)]−, the anion is monodeprotonated and acts as both a hydrogen-bond donor and acceptor. The anions are linked by pairs of O—H⋯O inter­actions, forming inversion dimers with R 2 2(8) ring motifs. These dimers are bridged by two dicyclo­hexyl­aminium cations via pairs of N—H⋯O hydrogen bonds, giving R 4 4(12) ring motifs, forming chains propagating along [010]. The chains are bridged by C—H⋯O inter­actions, forming a two-dimensional network lying parallel to (101)

1,3-Benzothia­zol-2-amine

In the crystal structure of the title compound, C7H6N2S, mol­ecules related by an inversion center are linked via N—H⋯N hydrogen bonds involving the amino groups, forming dimers. In turn, these dimers are linked via a second N—H⋯N hydrogen bond, forming an infinite two-dimensional network parallel to (011)

2,2′-(Propane-2,2-di­yl)bis­(1H-pyrrole)

The title compound, C11H14N2, crystallized with two independent mol­ecules (A and B) in the asymmetric unit. The two mol­ecules differ only slightly, with the pyrrole rings being inclined to one another at a dihedral angle of 87.67 (8)° in mol­ecule A and 88.09 (7)° in mol­ecule B. In the crystal, there are no classical hydrogen bonds, but the two pyrrole NH groups of one mol­ecule are involved in N—H⋯π inter­actions with the pyrrole rings of the other mol­ecule. In this manner, a compact box-like arrangement of the two independent mol­ecules is formed

4,4-Bis(1H-pyrrol-2-yl)penta­nol

The title achiral compound, C13H18N2O, crystallized in the chiral monoclinic space group P21. The pyrrole rings are inclined to one another by 62.30 (11)°, and the propanol chain is in an extended conformation. In the crystal, the two pyrrole NH groups are involved in inter­molecular N—H⋯O hydrogen bonds, leading to the formation of a helical arrangement propagating along the b axis. An inter­esting feature of the crystal structure is the absence of any conventional hydrogen bonds involving the hydr­oxy H atom. There is, however, a weak inter­molecular O—H⋯π inter­action involving one of the pyrrole rings

Bis(tetra­ethyl­ammonium) bis­(hydrogen l-tartrate) l-tartaric acid monohydrate

In the title compound, 2C8H20N+·2C4H5O6 −·C4H6O6·H2O, the presence of the two tetra­ethyl­ammonium cations is balanced by two hydrogen l-tartrate anions. Also present in the asymmetric unit are a mol­ecule of l-tartaric acid and a water mol­ecule. The various components are linked by O—H⋯O hydrogen bonds. In the crystal, two-dimensional networks are formed via O—H⋯O hydrogen bonds and C—H⋯O inter­actions involving the water mol­ecule, the hydrogen l-tartrate anions and the l-tartaric acid mol­ecules. These layers, which stack along [001], are separated by tetra­ethyl­ammonium cations. The latter are also involved in C—H⋯O inter­actions with the anions and the l-tartaric acid and water mol­ecules participating in the two-dimensional network

Dicyclo­hexyl­ammonium 3-[(hy­droxy­meth­yl)carbamo­yl]propano­ate

The title compound, C12H24N+·C5H8NO4 −, contains one dicyclo­hexyl­ammonium cation and one 3-[(hy­droxy­meth­yl)carbamo­yl]propano­ate anion in the asymmetric unit. In the crystal, the ions are linked by inter­molecular N—H⋯O and O—H⋯O hydrogen bonds, forming chains propagating along [100]

2,9-Dimethyl-1,10-phenanthrolin-1-ium (6-carb­oxy-4-hy­droxy­pyridine-2-carboxyl­ato-κ3 O 2,N,O 6)(4-hy­droxy­pyridine-2,6-dicarboxyl­ato-κ3 O 2,N,O 6)zincate(II) 2.35-hydrate: a proton-transfer compound

In the title compound, (C14H13N2)[Zn(C7H3NO5)(C7H4NO5)]·2.35H2O, the ZnII atom is coordinated by two N atoms and four O atoms from the carboxyl­ate groups of the 4-hy­droxy­pyridine-2,6-dicarboxyl­ate and 6-carb­oxy-4-hy­droxy­pyridine-2-carboxyl­ate ligands, forming a distored octa­hedral geometry. In the anion, the two pyridine rings are inclined to one another by 87.75 (13)°. Two types of robust O—H⋯O hydrogen bond synthons, viz. R 2 2(16) and R 6 6(42), link the anions to form a two-dimensional network parallel to the bc plane. Furthermore, O—H⋯O, N—H⋯O, N—H⋯N and weak C—H⋯O hydrogen bonds connect the two dimensional networks, forming a three-dimensional structure. In the crystal, there are also C—H⋯π and π–π inter­actions [centroid–centroid distances of 3.5554 (18) and 3.7681 (18) Å], and C=O⋯π inter­actions [O⋯centroid distance = 3.117 (2) Å] present. One of the three crystal water molecules shows an occupancy of 0.35

1,4-Bis(hex­yloxy)-2,5-diiodo­benzene

The centrosymmetric title compound, C18H28I2O2, crystallized in the monoclinic space group P21/c with the alkyl chains having extended all-trans conformations, similar to those in the centrosymmetric bromo analogue [Li et al. (2008 ▶). Acta Cryst. E64, o1930] that crystallized in the triclinic space group P . The difference between the two structures lies in the orientation of the two alkyl chains with respect to the C(aromatic)—O bond. In the title compound, the O—Calk­yl—Calk­yl—Calk­yl torsion angle is 55.8 (5)°, while in the bromo analogue this angle is −179.1 (2)°. In the title compound, the C-atoms of the alkyl chain are almost coplanar [maximum deviation of 0.052 (5) Å] and this mean plane is inclined to the benzene ring by 50.3 (3)°. In the bromo-analogue, these two mean planes are almost coplanar, making a dihedral angle of 4.1 (2)°. Another difference between the crystal structures of the two compounds is that in the title compound there are no halide⋯halide inter­actions. Instead, symmetry-related mol­ecules are linked via C—H⋯π contacts, forming a two-dimensional network

2,9-Dimethyl-1,10-phenanthrolin-1-ium (6-carb­oxy-4-hy­droxy­pyridine-2-carboxyl­ato-κ3 O 2,N,O 6)(4-hy­droxy­pyridine-2,6-dicarboxyl­ato-κ3 O 2,N,O 6)nickelate(II) 2.35-hydrate: a proton-transfer compound

The title proton-transfer compound, (C14H13N2)[Ni(C7H3NO5)(C7H4NO5)]·2.35H2O, consists of an [Ni(hypydc)(hypydcH)]− anion, a dmpH+ cation and 2.35 uncoordinated water mol­ecules (where hypydcH2 = 4-hy­droxy­pyridine-2,6-dicarb­oxy­lic acid and dmp = 2,9-dimethyl-1,10-phenanthroline). The NiII atom is coordinated by two N atoms and four O atoms from the carboxyl­ate groups of the (hypydc)2− and (hypydcH)− ligands, forming a distorted octa­hedral environment. In the anion, the two pyridine rings are inclined to one another by 89.24 (10)°. In the crystal, cations are linked via O—H⋯O hydrogen bonds forming dimers, graph-set [R 2 2(16)], centered about inversion centers. These dimers are further linked by other cation O—H⋯O hydrogen bonds, graph-set [R 6 6(42)], forming a two-dimensional network in (011). Additional inter­molecular O—H⋯O, N—H⋯O, N—H⋯N, and weak C—H⋯O hydrogen bonds, and π–π inter­actions [shortest centroid–centroid distance = 3.5442 (14) Å], connect the two dimensional networks, forming a three-dimensional arrangement. The H atoms of one of the methyl groups are disordered over two sites with equal occupancy