The crystal structures and Hirshfeld surface analysis of three new bromo-substituted 3-methyl-1-(phenyl-sulfon-yl)-1H-indole derivatives.

Three new 1H-indole derivatives, namely, 2-(bromo-meth-yl)-3-methyl-1-(phenyl-sulfon-yl)-1H-indole, C16H14BrNO2S, (I), 2-[(E)-2-(2-bromo-5-meth-oxy-phen-yl)ethen-yl]-3-methyl-1-(phenyl-sulfon-yl)-1H-indole, C24H20BrNO3S, (II), and 2-[(E)-2-(2-bromo-phen-yl)ethen-yl]-3-methyl-1-(phenyl-sulfon-yl)-1H-indole, C23H18BrNO2S, (III), exhibit nearly orthogonal orientations of their indole ring systems and sulfonyl-bound phenyl rings. Such conformations are favourable for inter-molecular bonding involving sets of slipped π-π inter-actions between the indole systems and mutual C-H⋯π hydrogen bonds, with the generation of two-dimensional monoperiodic patterns. The latter are found in all three structures, in the form of supra-molecular columns with every pair of successive mol-ecules related by inversion. The crystal packing of the compounds is additionally stabilized by weaker slipped π-π inter-actions between the outer phenyl rings (in II and III) and by weak C-H⋯O, C-H⋯Br and C-H⋯π hydrogen bonds. The structural significance of the different kinds of inter-actions agree with the results of a Hirshfeld surface analysis and the calculated inter-action energies. In particular, the largest inter-action energies (up to -60.8 kJ mol-1) are associated with pairing of anti-parallel indole systems, while the energetics of weak hydrogen bonds and phenyl π-π inter-actions are comparable and account for 13-34 kJ mol-1.

Crystal-structure determination and Hirshfeld surface analysis of two new thio-phene derivatives: (E)-N-{2-[2-(benzo[b]thio-phen-2-yl)ethen-yl]-5-fluoro-phen-yl}benzene-sulfonamide and (E)-N-{2-[2-(benzo[b]thio-phen-2-yl)ethen-yl]-5-fluoro-phen-yl}-N-(but-2-yn-1-yl)benzene-sulfonamide.

In the title compounds, C22H16FNO2S2 (I) and C26H20FNO2S2 (II), the benzo-thio-phene rings are essentially planar with maximum deviations of 0.009 (1) and 0.001 (1) Šfor the carbon and sulfur atom in compounds I and II, respectively. In I, the thio-phene ring system is almost orthogonal to the phenyl ring attached to the sulfonyl group, with a dihedral angle of 77.7 (1)°. In compound I, the mol-ecular structure is stabilized by weak C-H⋯O intra-molecular inter-actions formed by the sulfone oxygen atoms, which generate two S(5) ring motifs. In the crystal of I, N-H⋯O hydrogen bonds link the mol-ecules into R 2 2(8) rings, which are connected into a C(10) chain via C-H⋯F hydrogen bonds. Inter-molecular C-H⋯π inter-actions are also observed. In compound II, the mol-ecules are linked via C-H⋯O and C-H⋯F hydrogen bonding, generating infinite C(11) and C(13) chains running parallel to [010].

The synthesis, crystal structure and Hirshfeld surface analysis of the thio-phene derivatives 5-(phenyl-sulfon-yl)-5,6-di-hydro-benzo[4,5]thieno[3,2-j]phenanthridine and (E)-N-{2-[2-(benzo[b]thiophen-2-yl)ethenyl]phen-yl}-N-(prop-2-yn-1-yl)benzene-sulfonamide.

In both of the title compounds, C26H19NO2S2, (I), and C25H19NO2S2, (II), the benzo-thio-phene rings are essentially planar with maximum deviations of 0.026 (1) and -0.016 (1) Šfor the carbon and sulfur atoms in compounds (I) and (II), respectively. In (I), the thio-phene ring system is almost orthogonal to the phenyl ring attached to the sulfonyl group, subtending a dihedral angle of 88.1 (1)°, and the di-hydro-pyridine ring adopts a screw-boat conformation. In both compounds, the mol-ecular structure is consolidated by weak C-H⋯O intra-molecular inter-actions formed by the sulfone oxygen atoms, which generate S(5) ring motifs. In the crystal of II, mol-ecules are linked via C-H⋯O hydrogen bonds, generating C(7) chains running along the [100] direction. No significant inter-molecular inter-actions are observed in I.

The crystal structures and Hirshfeld surface analyses of four 3,5-diacetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl derivatives.

The title compounds, 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl benzoate, C20H19N3O4S (I), 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl isobutyrate 0.25-hydrate, C17H21N3O4S·0.25H2O (II), 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl propionate, C16H19N3O4S (III) and 4-(5-acetamido-3-acetyl-2-methyl-2,3-di-hydro-1,3,4-thia-diazol-2-yl)phenyl cinnamate chloro-form hemisolvate, C22H21N3O4S·0.5CHCl3 (IV), all crystallize with two independent mol-ecules (A and B) in the asymmetric unit in the triclinic P space group. Compound II crystallizes as a quaterhydrate, while compound IV crystallizes as a chloro-form hemisolvate. In compounds I, II, III (mol-ecules A and B) and IV (mol-ecule A) the five-membered thia-diazole ring adopts an envelope conformation, with the tetra-substituted C atom as the flap. In mol-ecule B of IV this ring is flat (r.m.s. deviation 0.044 Å). The central benzene ring is in general almost normal to the mean plane of the thia-diazole ring in each mol-ecule, with dihedral angles ranging from 75.8 (1) to 85.5 (2)°. In the crystals of all four compounds, the A and B mol-ecules are linked via strong N-H⋯O hydrogen bonds and generate centrosymmetric four-membered R 4 4(28) ring motifs. There are C-H⋯O hydrogen bonds present in the crystals of all four compounds, and in I and II there are also C-H⋯π inter-actions present. The inter-molecular contacts in the crystals of all four compounds were analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.

The crystal structures and Hirshfeld surface analysis of 6-(naphthalen-1-yl)-6a-nitro-6,6a,6b,7,9,11a-hexa-hydro-spiro-[chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zole-11,11'-indeno-[1,2-b]quinoxaline] and 6'-(naphthalen-1-yl)-6a'-nitro-6',6a',6b',7',8',9',10',12a'-octa-hydro-2H-spiro-[ace-naphthyl-ene-1,12'-chromeno[3,4-a]indolizin]-2-one.

The title compounds, 6-(naphthalen-1-yl)-6a-nitro-6,6a,6 b,7,9,11a-hexa-hydro-spiro-[chromeno[3',4':3,4]pyrrolo-[1,2-c]thia-zole-11,11'-indeno-[1,2-b]quinoxaline], C37H26N4O3S, (I), and 6'-(naphthalen-1-yl)-6a'-nitro-6',6a',6b',7',8',9',10',12a'-octa-hydro-2H-spiro-[ace-naphthyl-ene-1,12'-chromeno[3,4-a]indolizin]-2-one, C36H28N2O4, (II), are new spiro derivatives, in which both the pyrrolidine rings adopt twisted conformations. In (I), the five-membered thia-zole ring adopts an envelope conformation, while the eight-membered pyrrolidine-thia-zole ring adopts a boat conformation. An intra-molecular C-H⋯N hydrogen bond occurs, involving a C atom of the pyran ring and an N atom of the pyrazine ring. In (II), the six-membered piperidine ring adopts a chair conformation. An intra-molecular C-H⋯O hydrogen bond occurs, involving a C atom of the pyrrolidine ring and the keto O atom. For both compounds, the crystal structure is stabilized by inter-molecular C-H⋯O hydrogen bonds. In (I), the C-H⋯O hydrogen bonds link adjacent mol-ecules, forming R 2 2(16) loops propagating along the b-axis direction, while in (II) they form zigzag chains along the b-axis direction. In both compounds, C-H⋯π inter-actions help to consolidate the structure, but no significant π-π inter-actions with centroid-centroid distances of less than 4 Šare observed.

Crystal structures of two new isocoumarin derivatives: 8-amino-6-methyl-3,4-diphenyl-1H-isochromen-1-one and 8-amino-3,4-diethyl-6-methyl-1H-isochromen-1-one.

The title compounds, 8-amino-6-methyl-3,4-diphenyl-1H-isochromen-1-one, C22H17NO2, (I), and 8-amino-3,4-diethyl-6-methyl-1H-isochromen-1-one, C14H17NO2, (II), are new isocoumarin derivatives in which the isochromene ring systems are planar. Compound II crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In I, the two phenyl rings are inclined to each other by 56.41 (7)° and to the mean plane of the 1H-isochromene ring system by 67.64 (6) and 44.92 (6)°. In both compounds, there is an intra-molecular N-H⋯O hydrogen bond present forming an S(6) ring motif. In the crystal of I, mol-ecules are linked by N-H⋯π inter-actions, forming chains along the b-axis direction. A C-H⋯π inter-action links the chains to form layers parallel to (100). The layers are then linked by a second C-H⋯π inter-action, forming a three-dimensional structure. In the crystal of II, the two independent mol-ecules (A and B) are linked by N-H⋯O hydrogen bonds, forming -A-B-A-B- chains along the [101] direction. The chains are linked into ribbons by C-H⋯π inter-actions involving inversion-related A mol-ecules. The latter are linked by offset π-π inter-actions [inter-centroid distances vary from 3.506 (1) to 3.870 (2) Å], forming a three-dimensional structure.

Crystal structure and Hirshfeld surface analysis of 2-[(2-oxo-2H-chromen-4-yl)-oxy]acetic acid dimethyl sulfoxide monosolvate.

The title compound, C11H8O5·(CH3)2SO, is a new coumarin derivative. The asymmetric unit contains two coumarin mol-ecules (A and B) and two di-methyl-sulfoxide solvent mol-ecules (A and B). The dihedral angle between the pyran and benzene rings in the chromene moiety is 3.56 (2)° for mol-ecule A and 1.83 (2)° for mol-ecule B. In mol-ecule A, the dimethyl sulfoxide sulfur atom is disordered over two positions with a refined occupancy ratio of 0.782 (5):0.218 (5). In the crystal, mol-ecules are linked by O-H⋯O hydrogen bonds, forming chains running along the c-axis direction. The chains are linked by C-H⋯O hydrogen bonds, forming layers parallel to the ac plane. In addition, there are also C-H⋯π and π-π inter-actions present within the layers. The inter-molecular contacts in the crystal have been analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots, which indicate that the most important contributions to the packing are from H⋯H (33.9%) and O⋯H/H⋯O (41.2%) contacts.

The crystal structures of two new coumarin derivatives: 2-(4-{2-[(2-oxo-2H-chromen-4-yl)-oxy]acet-yl}piperazin-1-yl)acetamide and N-(2,4-di-meth-oxy-benz-yl)-2-[(2-oxo-2H-chromen-4-yl)-oxy]acetamide.

The title compounds, 2-(4-{2-[(2-oxo-2H-chromen-4-yl)-oxy]acet-yl}piperazin-1-yl)acetamide, C17H19N3O5, (I), and N-(2,4-di-meth-oxy-benz-yl)-2-[(2-oxo-2H-chromen-4-yl)-oxy]acetamide, C20H19NO6, (II), are new coumarin derivatives. In compound (I), the six-membered piperazine adopts a chair conformation. The dihedral angles between the mean planes of the chromene ring and amide plane is 82.65 (7)° in (I) and 26.2 (4)° in (II). The dihedral angles between the mean planes of the chromene ring and the four planar C atoms of the piperazine ring in (I) and the benzene ring in (II) are 87.66 (6) and 65.0 (4)°, respectively. There are short intra-molecular contacts in both mol-ecules forming S(5) ring motifs, viz. N-H⋯N and C-H⋯O in (I), and N-H⋯O and C-H⋯N in (II). In the crystals of both compounds, mol-ecules are linked by N-H⋯O hydrogen bonds, forming chains along [10] in (I) and [010] in (II). The chains are linked by C-H⋯O hydrogen bonds, forming layers parallel to the ab plane in the crystals of both compounds. In the crystal of (I), there are also C-H⋯π and offset π-π inter-actions [inter-centroid distance = 3.691 (1) Å] present within the layers. In the crystal of (II), there are only weak offset π-π inter-actions [inter-centroid distance = 3.981 (6) Å] present within the layers. The inter-molecular contacts in the crystals of both compounds have been analysed using Hirshfeld surface analysis and two-dimensional fingerprint plots.

The crystal structures and Hirshfeld surface analysis of N',N'''-((1E,1'E)-{[methyl-enebis(-oxy)]bis-(6-bromo-3,1-phenyl-ene)}bis-(methan-ylyl-idene))bis-(isonicotinohydrazide) dihydrate and N',N'''-((1E,1'E)-{[butane-1,4-diylbis(-oxy)]bis-(2,1-phenyl-ene)}bis-(methan-ylyl-idene))bis-(isonicotino-hydrazide) [+ solvent].

The title compounds, C27H20Br2N6O4·2H2O, (I), and C30H28N6O4·[+ solvent], (II), both crystallize with one half-mol-ecule in the asymmetric unit. The whole mol-ecule of (I) is generated by twofold rotation symmetry, with the twofold rotation axis bis-ecting the C atom of the -O-CH2-O- bridge. This results in a folded or U-shaped conformation of the mol-ecule. The whole mol-ecule of (II) is generated by inversion symmetry, with the central CH2-CH2 bond of the -O-(CH2)4-O- bridge being located about a center of inversion. This results in a step-like conformation of the mol-ecule. The central C(=O)N-N=C regions of the isonicotinohydrazide moieties in both compounds are planar and the configuration about the imine C=N bonds is E. In compound (I), the benzene and pyridine rings are inclined to each other by 37.60 (6)°. The two symmetry-related pyridine rings are inclined to each other by 74.24 (6)°, and the two symmetry-related benzene rings by 7.69 (6)°. In compound (II), the benzene and pyridine rings are inclined to each other by 25.56 (11)°. The symmetry-related pyridine rings are parallel, as are the two symmetry-related benzene rings. In the crystal of (I), a pair of water mol-ecules link the organic mol-ecules via Owater-H⋯O and Owater-H⋯N hydrogen bonds, forming chains along [001], and enclosing an R 4 2(8) and two R 1 2(5) ring motifs. The chains are linked by N-H⋯Npyridine hydrogen bonds, forming a supra-molecular framework. There are also a number of C-H⋯O hydrogen bonds, and C-H⋯π and offset π-π inter-actions [inter-planar distance = 3.294 (1) Å] present reinforcing the framework. In the crystal of (II), mol-ecules are linked by N-H⋯Npyridine hydrogen bonds, forming a supra-molecular framework. Here too there are also a number of C-H⋯O hydrogen bonds present, and a C-H⋯π inter-action, reinforcing the framework. For compound (II), a region of disordered electron density was corrected for using the SQUEEZE [Spek (2015 ▸). Acta Cryst. C71, 9-18] routine in PLATON. Their formula mass and unit-cell characteristics were not taken into account during refinement.

The crystal structures of 6'-(4-chloro-phen-yl)- and 6'-(4-meth-oxy-phen-yl)-6a'-nitro-6a',6b',7',9',10',12a'-hexa-hydro-2H,6'H,8'H-spiro-[ace-naphthyl-ene-1,12'-chromeno[3,4-a]indolizin]-2-one.

In the title compounds, C32H25ClN2O4 (I) and C33H28N2O5 (II), the six-membered pyran and piperidine rings adopt envelope and chair conformations, respectively. The five-membered pyrrolidine rings adopt twist conformations. Compound (II) crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. In all three mol-ecules there is a C-H⋯O intra-molecular hydrogen bond present enclosing an S(7) ring motif. In (I), both oxygen atoms of the nitro group are disordered, while in (II) the meth-oxy-benzene group is disordered in mol-ecule B. The geometries were regularized by soft restraints. In the crystal of (I), mol-ecules are linked by C-H⋯O hydrogen bonds, forming chains along [010]. The chains are linked by C-H⋯Cl hydrogen bonds, forming layers parallel to (10). Within the layer there are C-H⋯π inter-actions present. In the crystal of (II), the A and B mol-ecules are linked via C-H⋯O hydrogen bonds, forming a square four-membered A-B-A-B unit. These units are linked by a number of C-H⋯π inter-actions, forming a three-dimensional supra-molecular structure.

Crystal structure of 6-(4-chloro-phen-yl)-6a-nitro-6a,6b,8,9,10,12a-hexa-hydro-6H,7H-spiro[chromeno[3,4-a]indolizine-12,11'-indeno-[1,2-b]quinoxaline].

The title compound, C35H27ClN4O3, crystallized with two independent mol-ecules (A and B) in the asymmetric unit. In both mol-ecules, the pyran and pyridine rings adopt envelope and chair conformations, respectively. The conformation of the pyrrolidine and cyclo-pentene rings differ in the two mol-ecules; twisted and flat, respectively, in mol-ecule A, but envelope and twisted, respectively, in mol-ecule B. In both mol-ecules, there is a C-H⋯N intra-molecular hydrogen bond present. In both mol-ecules, the oxygen atoms of the nitro groups are disordered as is the chlorine atom in mol-ecule B. In the crystal, the B mol-ecules are linked by C-H⋯O hydrogen bonds, forming -B-B-B- chains along [010], and by C-H⋯π inter-actions. The A and B mol-ecules are also linked by a number of C-H⋯π inter-actions, resulting in the formation a supra-molecular three-dimensional structure. In mol-ecule A, the nitro group oxygen atoms are disordered over two positions with refined occupancy ratios of the nitro group oxygen atoms O3A and O4A in 0.59 (2):0.41 (2) while in molecule B one of the nitro O atoms is disordered over two positions with a refined occupancy ratio of 0.686 (13):0.314 (13) and the chlorine atoms is disordered over two positions with a refined occupancy ratio of 0.72 (3):0.28 (3).

Crystal structure of 1,4-bis-(3-ammonio-prop-yl)piperazine-1,4-diium bis-[dichromate(VI)].

The asymmetric unit of the organic-inorganic title salt, (C10H28N4)[Cr2O7]2, comprises one half of an 1,4-bis-(3-ammonio-prop-yl)piperazinediium cation (the other half being generated by the application of inversion symmetry) and a dichromate anion. The piperazine ring of the cation adopts a chair conformation, and the two CrO4 tetra-hedra of the anion are in an almost eclipsed conformation. In the crystal, the cations and anions form a layered arrangement parallel to (001). N-H⋯O hydrogen bonds between the cations and anions and additional C-H⋯O inter-actions lead to the formation of a three-dimensional network structure.

Crystal structure of 2-amino-5-nitro-pyridinium sulfamate.

The title mol-ecular salt, C5H6N3O2 (+) ·H2NO3S(-), was obtained from the reaction of sulfamic acid with 2-amino-5-nitro-pyridine. A proton transfer from sulfamic acid to the pyridine N atom occurred, resulting in the formation of a salt. As expected, this protonation leads to the widening of the C-N-C angle of the pyridine ring, to 122.9 (3)°, with the pyridinium ring being essentially planar (r.m.s. deviation = 0.025 Å). In the crystal, the ion pairs are joined by three N-H⋯O and one N-H⋯N hydrogen bonds in which the pyridinium N atom and the amino N atom act as donors, and are hydrogen bonded to the carboxyl-ate O atoms and the N atom of the sulfamate anion, thus generating an R (3) 3(22) ring motif. These motifs are linked by further N-H⋯O hydrogen bonds enclosing R (3) 3(8) loops, forming sheets parallel to (100). The sheets are linked via weak C-H⋯O hydrogen bonds, forming a three-dimensional structure. The O atoms of the nitro group are disordered over two sets of sites with a refined occupancy ratio of 0.737 (19):0.263 (19).

Crystal structure of bis-(thio-cyanato-κS)bis-(thio-urea-κS)mercury(II).

In the title complex, [Hg(NCS)2(CH4N2S)2], the Hg(II) atom is four-coordinated having an irregular four-coordinate geometry composed of four thione S atoms of two thio-cyanate groups and two thio-urea groups. The S-Hg-S angles are 172.02 (9)° for the trans-thio-cyanate S atoms and 90.14 (5)° for the cis-thio-urea S atoms. The mol-ecular structure is stabilized by an intra-molecular N-H⋯S hydrogen bond, which forms an S(6) ring motif. In the crystal, mol-ecules are linked by a number of N-H⋯N and N-H⋯S hydrogen bonds, forming a three-dimensional framework. The first report of the crystal structure of this compound appeared in 1966 [Korczynski (1966 ▶). Rocz. Chem. 40, 547-569] with an extremely high R factor of 17.2%, and no mention of how the data were collected.

Synthesis, growth, structural and optical studies of a novel organic Piperazine (bis) p-toluenesulfonate single crystal.

A novel organic single crystal of Piperazinium (bis) p-toluenesulfonate (PPTS) was grown by a slow evaporation solution growth technique. The structure of the grown crystal was determined using single crystal X-ray diffraction analysis. The PPTS crystal belongs to the triclinic crystal system with space group of P1¯. The presence of functional groups was confirmed by FTIR spectral analysis. The optical transmittance range and cut-off wavelength were identified by UV-vis-NIR spectral studies. The luminescent properties of PPTS crystal were investigated. The thermal behavior of PPTS crystal was studied by TG-DT analyses.

2-Amino-6-methyl-pyridinium 4-methyl-benzene-sulfonate.

In the asymmetric unit of the title salt, C6H9N2 (+)·C7H7O3S(-), there are two independent 2-amino-6-methyl-pyridinium cations and two independent 4-methyl-benzene-sulfonate anions. Both cations are protonated at their pyridine N atoms and their geometries reveal amine-imine tautomerism. In the 4-methyl-benzene-sulfonate anions, the carboxyl-ate groups are twisted out of the benzene ring planes by 88.4 (1) and 86.2 (2)°. In the crystal, the sulfonate O atoms of an anion inter-act with the protonated N atoms and the 2-amino groups of a cation via a pair of N-H⋯O hydrogen bonds, forming an R 2 (2)(8) ring motif. These motifs are connected via N-H⋯O hydrogen bonds, forming chains running along the a-axis direction. Within the chains there are weak C-H⋯O hydrogen bonds present. In addition, aromatic π-π stacking inter-actions [centroid-centroid distances = 3.771 (2), 3.599 (2), 3.599 (2) and 3.497 (2) Å] involving neighbouring chains are also observed.

2-Amino-6-methyl-pyridinium 2,2,2-tri-chloro-acetate.

In the asymmetric unit of the title mol-ecular salt, C6H9N2 (+)·C2Cl3O2 (-), there are two independent 2-amino-6-methyl-pyridinium cations and two independent tri-chloro-acetate anions. The pyridine N atom of the 2-amino-6-methyl-pyridine mol-ecule is protonated and the geometries of these cations reveal amine-imine tautomerism. Both protonated 2-amino-6-methyl-pyridinium cations are essentially planar [maximum deviations = 0.026 (2) and 0.012 (2) Å]. In the crystal, the protonated N atom and the 2-amino group of the cation are hydrogen bonded to the carboxyl-ate O atoms of the anion via a pair of N-H⋯O hydrogen bonds, forming an R 2 (2)(8) ring motif. These motifs are connected via N-H⋯O and C-H⋯O hydrogen bonds to form slabs parallel to (101).

2-Amino-5-nitro-pyridinium hydrogen oxalate.

In the cation of the title mol-ecular salt, C5H6N3O2 (+)·C2HO4 (-), the dihedral angle between the aromatic ring and the nitro group is 3.5 (3)°; in the anion, the dihedral angle between the CO2 and CO2H planes is 10.5 (2)°. In the crystal, the anions are linked into [100] chains by O-H⋯O hydrogen bonds. The cations cross-link the chains by way of N-H⋯O hydrogen bonds and the structure is consolidated by C-H⋯O inter-actions.

Diammonium tetra-kis-(iso-thio-cyanato)-zincate-1,4,10,13,16-hexa-oxa-cyclo-octa-deca-ne-water (1/2/1).

The title compound, (NH4)2[Zn(NCS)4]·2C12H24O6·H2O, the result of the reaction of ammonium thio-cyanate, 18-crown-6 and zinc(II) chloride in aqueous solution, exhibits an unusual supra-molecular structure. The Zn atom, two of the thio-cyanate chains and a water mol-ecule, disordered over two positions, lie on a mirror plane. The macrocycle adopts a conformation with approximate D 3d symmetry. The ammonium mol-ecules are contained within the bowl of the macrocycle via extensive N-H⋯O hydrogen bonds and the complex mol-ecules are linked via N-H⋯S hydrogen bonds, forming chains along the c-axis direction. The macrocycle is disordered over two positions [refined occupancy ratio = 0.666 (8):0.334 (8)]. The S atoms of two iso-thio-cyanate ligands are disordered within and about the mirror plane.

N (2)-(4-Meth-oxy-salicyl-idene)arginine hemihydrate.

The title compound, C14H20N4O4·0.5H2O [systematic name: (2S)-5-{[amino-(iminium-yl)meth-yl]amino}-2-{[(1Z)-4-meth-oxy-2-oxido-benzyl-idene]aza-nium-yl}penta-noate hemihydrate], has been synthesized by the reaction of l-arginine and 4-meth-oxy-salicyl-aldehyde and crystallizes with two independent substituted l-arginine mol-ecules and one water mol-ecule of solvation in the asymmetric unit. Each mol-ecule exists as a zwitterion and adopts a Z configuration about the central C=N. The mol-ecular conformation is stabilized by strong intra-molecular N-H⋯O hydrogen bonds that generate S(6) and S(10) ring motifs. Inter-molecular N-H⋯O and O-H⋯O hydrogen bonds involving also the water mol-ecule and weak inter-molecular C-H⋯Owater inter-actions link the mol-ecules into an infinite one-dimensional ribbon structure extending along the b axis. The known (2S) absolute configuration for l-arginine was invoked. Weak intermolecular C-H⋯π interactions are also present.