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1.
ACS Omega ; 9(27): 29310-29319, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39005785

RESUMO

The hydrothermal reaction of 2-MeIm (2-MeIm: 2-methylimidazole) with nickel sulfate hexahydrate in methanol afforded a mononuclear complex formulated as [Ni(SO4)(2-MeIm)2(H2O)3]·CH3OH (1). The title compound was described by X-ray single-crystal diffraction, thermal assessment, IR, and UV-vis spectroscopy. The crystal structure of 1 is composed of segregated [Ni(SO4)(2-MeIm)2(H2O)3] neutral entities and a solvent methanol molecule. Two (2-MeIm) ligands, a sulfate group, and a water molecule reside in the equatorial positions of the vertices in this 6-fold coordination. Two aqua ligands lay in the apical positions, resulting in a subtly distorted octahedral framework, as was supported by spectroscopic analysis. The complex's self-assembly is firmly governed by robust O-H···O/N-H···O interactions. Further details on these bonds have been furnished via Hirshfeld surface scrutiny and 2D fingerprint plots. As proven by TGA/DSC analysis, raising the temperature of 1 above 60 °C instigates progressive decomposition stages, which culminates in the production of metal oxide as the ultimate product at 700 °C. The optical analysis suggests the dielectric nature of the material with large direct and indirect gap energies of 5.25 and 4.96 eV, respectively. The results of magnetic studies suggest that 1 undergoes a transition to a magnetically ordered state below 6 K.

2.
ACS Omega ; 9(27): 29263-29273, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39005796

RESUMO

In this work, we use a combination of dispersion-corrected density functional theory (DFT-D3) and the TiberCAD framework for the first time to investigate a newly designed and synthesized class of (C6H10N2)[CuCl4] 2D-type perovskite. The inter- and intra-atomic reorganization in the crystal packing and the type of interaction forming in the active area have been discussed via Hirshfeld surface (HS) analyses. A distinct charge transfer from CuCl4 to [C6H10N2] is identified by frontier molecular orbitals (FMOs) and density of states (DOS). This newly designed narrow-band gap small-molecule perovskite, with an energy gap (E g) of 2.11 eV, exhibits a higher fill factor (FF = 81.34%), leading to an open-circuit voltage (V oc) of 1.738 V and a power conversion efficiency (PCE) approaching ∼10.20%. The interaction between a donor (D) and an acceptor (A) results in a charge transfer complex (CT) through the formation of hydrogen bonds (Cl-H), as revealed by QTAIM analysis. These findings were further supported by 2D-LOL and 3D-ELF analyses by visualizing excess electrons surrounding the acceptor entity. Finally, we performed numerical simulations of solar cell structures using TiberCAD software.

3.
RSC Adv ; 14(25): 17413-17433, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38818365

RESUMO

Colorless single crystals of the zero-dimensional hybrid compound, (C6H10N2)2[PdCl6]·2H2O were acquired through the slow evaporation technique. The crystal structure was explored using SC-XRD, which demonstrates that the material crystallizes in the centrosymmetric space group P1̄ of the triclinic system. The density functional theory method at the B3LYP/Lan2mb basis set level was employed to establish the optimized geometry and vibrational frequencies of the title compound. An acceptable correspondence was observed between the results obtained through calculation and the experimental data, including the structure, and IR spectra. The optical characteristics revealed a direct band gap energy of 2.35 eV, validating the semiconductor characteristics of this new material. The results suggest strong agreement with the experimental data and validate the involvement of metal orbitals in defining the HOMO-LUMO boundary. Simultaneous TGA-DTA shows that this material remains solid up to 210 °C. Beyond these temperatures, a gradual decomposition process occurs, extending up to 440 °C and unfolding in several steps. This process entails the liberation of diverse compounds, encompassing organic molecules, and the evaporation of chlorine ions, ultimately leading to the formation of palladium oxide (PdO) as the final product. When given to rats with gastric ulcers at a dose of 100 mg kg-1, these compounds inhibit the key enzyme responsible for neutrophil infiltration as myeloperoxidase (MPO) by 38.7%. The compound also alleviates cellular damage induced by free radicals, demonstrated by a notable 48.3% decrease in thiobarbituric acid reactive substance rates (TBARS) compared to untreated rats. Additionally, these compounds bring about a substantial 30.6% reduction in the surface area of ulcers.

4.
RSC Adv ; 13(43): 30168-30175, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37849697

RESUMO

A series of P5+ - doped La2Mo2O9 phases with different concentrations of P5+ were prepared using conventional solid-state reactions. The formation of phase-pure P5+-doped La2Mo2O9 has been monitored by powder X-ray diffraction, thermal analysis, conductivity measurements, Raman, and FT-IR absorption techniques. The structure and lattice parameters of La2Mo2-yPyO9-y/2 are obtained from Rietveld refinement. The effect of substituting P for Mo reveals that the phase transition which occurs in La2Mo2O9 around 560 °C disappears when y > 0.02, as demonstrated by thermal analysis. Pure P5+-doped phases with monoclinic structure (α-form, the space group P21) were observed for the concentration of optically active ions up to y = 0.02. When the concentration of P5+ ions is higher, a cubic structure (ß-form, the space group P213) starts to appear. However, up to the concentration of y = 0.03 of the P5+ ion a mixture of the monoclinic and cubic phases has been observed. From infrared and Raman analysis it is confirmed that different vibration modes arise from the vibration of molybdenum-oxygen bands. Mo-O bond lengths are also found to be independent of P-doping.

5.
RSC Adv ; 13(37): 26122-26133, 2023 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-37675187

RESUMO

In the present investigation, a new hybrid crystal, with the formula [(C4H9)4P]2Cd2Cl6 has been synthesized by the slow evaporation method at room temperature. It was characterized by X-ray diffraction (XRD), Hirshfeld surface, differential scanning calorimetry (DSC), optical measurement and complex impedance. Single crystal X-ray diffraction structural analysis revealed that the title compound crystallizes in the triclinic system with space group P1̄ and cell parameters: a = 11.972 (1) Å, b = 15.418 (1) Å, c = 15.426 (2) Å, αa = 68.71 (2) °, ß = 73.20 (3) ° and γ = 74.39 (2)°. The Hirshfeld surface analysis was conducted to investigate intermolecular interactions and associated 2D fingerprint plots, revealing quantitatively the relative contribution of these interactions in the crystal cohesion. DSC studies indicated one phase transition at about 348 K. Optical absorption spectra show that the band gap of [(C4H9)4P]2Cd2Cl6 is approximately 2.65 eV. The Nyquist plot showed only one semicircular arc, representing the grain effect in the electrical conduction. The thermal evolution of the conductivity of the grains presents an Arrhenius type behavior, demonstrating that charge carriers have to overcome different energy barriers while conducting and relaxing. Besides, the AC conductivity was analyzed by Jonscher's law and the conduction mechanism is well ensured by the correlated barrier hopping (CBH) model.

6.
ACS Omega ; 8(17): 15075-15082, 2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37151535

RESUMO

Crystals of the new organic-inorganic material (DAP-H2)[CuBr4] (1); (DAP = hexahydrodiazepine (C5H14N2)) were successfully synthesized by slow evaporation and characterized by single-crystal X-ray diffraction, infrared spectroscopy, thermal analysis, UV-Vis-NIR diffuse reflectance spectroscopy, and magnetic measurements. X-ray investigation demonstrates that 1 crystallizes in the monoclinic space group C2/c. The supramolecular crystal structure of 1 is guided by several types of hydrogen bonding which connect anions and cations together into a three-dimensional network. The optical band gap was determined by diffuse reflectance spectroscopy to be 1.78 eV for a direct allowed transition, implying that it is suitable for light harvesting in solar cells. The vibrational properties of this compound were studied by infrared spectroscopy, while its thermal stability was established by simultaneous TGA-DTA from ambient temperature to 600 °C. The study of the photoresponse behavior of an optoelectronic device, based on (C5H14N2)[CuBr4], has shown a power conversion efficiency (PCE) of 0.0017%, with J sc = 0.0208 mA/cm2, V oc = 313.7 mV, and FF = 25.46. Temperature dependent magnetic susceptibility measurements in the temperature range 1.8-310 K reveal weak antiferromagnetic interactions via the two-halide superexchange pathway [2J/k B = -8.4(3) K].

7.
ChemSusChem ; 16(11): e202202313, 2023 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-37075747

RESUMO

Lead halide perovskites are attractive pigments to fabricate solar cells in the laboratory, owing to their high power conversion efficiency. However, given the presence of Pb, such materials also have a high level of toxicity and are carcinogenic for humans and aquatic life. Arguably, this hampers their acceptability for immediate commercialization. This study entails the synthesis, optoelectronic properties, and photovoltaic parameters of two-dimensional copper-based perovskites as an environmentally benign alternative to lead-based perovskites. The perovskites - (CH3 NH3 )2 CuCl4-x Brx with x=0.3 and 0.66 - are derivatives of the stable (CH3 NH3 )2 CuCl4 . The single crystals and powders diffractograms suggest compositions with variations in Cl/Br ratio and dissimilar bromine localization in the inorganic framework. The copper mixed halide perovskite exhibits a narrow absorption with a bandgap of 2.54-2.63 eV related to the halide ratio disparity (crystal color variation). These findings demonstrate the impact of halides to optimize the stability of methylammonium copper perovskites and provide an effective pathway to design eco-friendly perovskites for optoelectronic applications.


Assuntos
Compostos de Cálcio , Cobre , Humanos , Óxidos , Eletrônica
8.
RSC Adv ; 12(52): 33516-33524, 2022 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-36505725

RESUMO

A one dimensional (1D) perovskite-type (C6H7NBr)3[CdBr5] (abbreviated 4-BAPC) was synthesized by slow evaporation at room temperature (RT). 4-BAPC crystalizes in the monoclinic system with the space group P21/c. The 1D inorganic chains are formed by corner sharing CdBr6 octahedra. Thermal measurement shows that 4-BAPC is stable up to 190 °C. Optical characterization demonstrates that the grown crystal is an indirect bandgap material with a bandgap value of 3.93 eV, which is consistent with theoretical calculations. The electronic structure, calculated using density functional theory, reveals that the valence band originates from a combination of Br-4p orbitals and Cd-4d orbitals, whereas the conduction band originates from the Cd-5s orbitals. The photoluminescence spectroscopy shows that the obtained material exhibits a broad-band white light emission with extra-high CRI of 98 under λ exc = 380 nm. This emission is mainly resulting from the self-trapped exciton recombinations within the inorganic CdBr6 octahedron, and the fluorescence within the organic conjugated ammonium salt.

9.
3 Biotech ; 12(9): 191, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35910291

RESUMO

In the present study we focused on the anti-asthmatic and antioxidant effects of Zingiber officinalis roscoe L. (ZO) aqueous extract. This study includes 20 adult male rats, which were grouped into four; Group I: control group; Group II: asthmatic group (Ovalbumin sensitized/challenge model, Oval group); Group III: received ovalbumin sensitized/challenge associated a dose of 207 mg/kg body weight (BW) of ZO (Oval + D1 group); Group IV: received ovalbumin sensitized/challenge associated a dose of 414 mg/k BW of ZO (Oval + D2 group). After 21 days, blood and lung samples were collected for biochemical, hematological, and histopathological analyses. The ameliorative effect of ZO phytochemical compounds was also assessed by in silico approach on transducer and activator of transcription 6 (STAT6) and tumor necrosis factor-α (TNF-α) receptors. The oxidative/antioxidative status was evaluated in the lung tissues. Our results show that ZO extract alleviated the ovalbumin-induced hematological and biochemical disruptions associated oxidative injury. In fact, white and red blood cells (WBC and RBC, respectively), aspartate aminotransaminase (ASAT), malondialdehyde (MDA), glutathione (GSH), and glutathione peroxidase (GPx) were significantly disrupted (p < 0.05) in Oval group and alleviated following ZO treatment. Besides, several histopathological features were outlined in lung tissues of Oval group. Interestingly, ZO was found to exert ameliorative effects on tissue level. In silico analyses, particularly the binding affinities, the number of H-bonds, the embedding distance and the molecular interactions of ZO phytochemical compounds with either STAT6 or TNF-α supported the in vivo results. These findings confirm the potential ethno-pharmacological effects of ZO against asthma and its associated complications.

10.
3 Biotech ; 12(5): 112, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35462952

RESUMO

Ginger (Zingiber officinale) is considered as a nutraceutical spice, which possesses several health promotion and benefits. This study was carried out to investigate the phyto-chemical composition, the antioxidant capacities, the drug-likeness, and pharmacokinetic properties of ginger extract on kidney injury-associated osteoporosis in rats. Phenolic and flavonoid contents were assessed by standard chemical analysis methods and HPLC. In vivo protective effect was based on the use of female rats to evaluate the effect on renal injury as a result of combined osteoporosis using biochemical markers, oxidative status, and histological analyses. Results showed that ZO contained appreciable amounts of phenolics and flavonoids and it exhibited high scavenging activity. Ovariectomy-associated corticotherapy induced severe renal injury marked by altered biochemical markers (creatinine, urea, and uric acid), reduced GFR, significative oxidative damage signs, and disrupted antioxidant status in the combined osteoporotic rats. The histopathological examination revealed structural modifications of kidney tissues. However, all these changes were reversed following the use of ZO. These results confirm the renoprotective and antioxidant potential of ginger against renal injuries in osteoporotic rats.

11.
RSC Adv ; 12(17): 10431-10442, 2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35425012

RESUMO

In this work, we report two zero-dimensional Cd-based hybrid compounds, denoted CdACP and CdODA, where the Cd atoms adopt tetrahedral geometry. The optical analysis reveals that these materials are classified as wide-gap semi-conductors which makes them suitable for optoelectronic applications. The photoluminescence analysis proves the wavelength dependent white-light emission behavior of the investigated materials. The structural-optical property studies show that, thanks to the heavy halide effect, the CdACP exhibits both fluorescence and room temperature phosphorescence through harvesting triplet states. Meanwhile, in contrast to CdACP, the white light emission from CdODA is purely fluorescence in nature. In fact, within CdODA, both C-H⋯π and N-H⋯N interactions facilitate the intramolecular proton transfer (ESIPT) between the different cations which leads to ultra-fast fluorescence through excited state ESIPT. Under sub-gap excitations, the inorganic sub-lattice is responsible for the blue-green emission through the STE mechanism, while the organic cations contribute by an intense red emission.

12.
Pharmaceuticals (Basel) ; 15(2)2022 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-35215242

RESUMO

Fighting against the emergent coronavirus disease (COVID-19) remains a big challenge at the front of the world communities. Recent research has outlined the potential of various medicinal herbs to counteract the infection. This study aimed to evaluate the interaction of artemisinin, a sesquiterpene lactone extracted from the Artemisia genus, and its derivatives with the SARS-CoV-2 main protease. To assess their potential use against COVID-19, the interactions of the main active principle of Artemisia with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) main protease (Mpro) was investigated through in silico probing. Our results showed that artemesinin and its derivatives manifested good oral absorption and bioavailability scores (0.55). They potently bound to the Mpro site of action-specifically, to its Cys145 residue. The selected compounds established two to three conventional hydrogen bonds with binding affinities ranging between -5.2 and -8.1 kcal/mol. Furthermore, artemisinin interactions with angiotensin converting enzyme 2 (ACE2) were dependent on the ACE2 allelic variants. The best score was recorded with rs961360700. A molecular dynamic simulation showed sufficient stability of the artemisinin-Mpro complex on the trajectory of 100 ns simulation frame. These binding interactions, together with drug-likeness and pharmacokinetic findings, confirmed that artemisinin might inhibit Mpro activity and explain the ethnopharmacological use of the herb and its possible antiviral activity against SARS-CoV-2 infection inducing COVID-19. Nevertheless, it interacted differently with the various ACE2 allelic variants reported to bind with the SARS-CoV-2 spike protein.

13.
Inorg Chem ; 60(18): 14294-14301, 2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34472330

RESUMO

We report a novel synthetic procedure for the high-yield synthesis of metal-organic frameworks (MOFs) with fcu topology with a UiO-66-like structure starting from a range of commercial ZrIV precursors and various substituted dicarboxylic linkers. The syntheses are carried out by grinding in a ball mill the starting reagents, namely, Zr salts and the dicarboxylic linkers, in the presence of a small amount of acetic acid and water (1 mL total volume for 1 mmol of each reagent), followed by incubation at either room temperature or 120 °C. Such a simple "shake 'n bake" procedure, inspired by the solid-state reaction of inorganic materials, such as oxides, avoids the use of large amounts of solvents generally used for the syntheses of Zr-MOF. Acidity of the linkers and the amount of water are found to be crucial factors in affording materials of quality comparable to that of products obtained under solvo- or hydrothermal conditions.

14.
Molecules ; 25(22)2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-33238608

RESUMO

A series of neutral mixed-ligand [HB(pz)3]Ag(PR3) silver(I) complexes (PR3 = tertiary phosphine, [HB(pz)3]- = tris(pyrazolyl)borate anion), and the corresponding homoleptic [Ag(PR3)4]BF4 compounds have been synthesized and fully characterized. Silver compounds were screened for their antiproliferative activities against a wide panel of human cancer cells derived from solid tumors and endowed with different platinum drug sensitivity. Mixed-ligand complexes were generally more effective than the corresponding homoleptic derivatives, but the most active compounds were [HB(pz)3]Ag(PPh3) (5) and [Ag(PPh3)4]BF4 (10), both comprising the lipophilic PPh3 phosphine ligand. Detailed mechanistic studies revealed that both homoleptic and heteroleptic silver complexes strongly and selectively inhibit the selenoenzyme thioredoxin reductase both as isolated enzyme and in human ovarian cancer cells (half inhibition concentration values in the nanomolar range) causing the disruption of cellular thiol-redox homeostasis, and leading to apoptotic cell death. Moreover, for heteroleptic Ag(I) derivatives, an additional ability to damage nuclear DNA has been detected. These results confirm the importance of the type of silver ion coordinating ligands in affecting the biological behavior of the overall corresponding silver complexes, besides in terms of hydrophilic-lipophilic balance, also in terms of biological mechanism of action, such as interaction with DNA and/or thioredoxin reductase.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Fosfinas/química , Prata/química , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , Complexos de Coordenação/síntese química , Relação Dose-Resposta a Droga , Humanos , Ligantes , Estrutura Molecular
15.
RSC Adv ; 10(10): 5864-5873, 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35497437

RESUMO

A slow evaporation method has permitted the crystallization of two novel crystals of (2-aminomethyl)pyridindiumdihalide C6H10N2,2Br (1) and C6H10N2,2Cl·H2O (2). The structures of the prepared compounds (1) and (2) were elucidated by single-crystal X-ray diffraction which revealed that they crystallize, respectively, with triclinic and monoclinic symmetries. Their crystal packing was stabilized by non-covalent interactions, including N-H⋯Br, C-H⋯Br, N-H⋯Cl, O-H⋯Cl and N-H⋯O hydrogen bonds. 3-D Hirshfeld surface analysis followed by 2-D fingerprint schemes gives insights into the intermolecular interactions in the crystalline structure. Furthermore, the FT-IR spectroscopy of these two compounds was carried out. The synthesized products were also screened for in vitro antioxidant and antimicrobial activities, which reveals their favourable antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) as well as the discolouration of ß-carotene.

16.
Chem Cent J ; 12(1): 24, 2018 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-29497955

RESUMO

BACKGROUND: Complexes of imidazole derivatives with transition metal ions have attracted much attention because of their biological and pharmacological activities, such as antimicrobial, antifungal, antiallergic, antitumoural and antimetastatic properties. In addition, imidazoles occupy an important place owing to their meaningful catalytic activity in several processes, such as in hydroamination, hydrosilylation, Heck reaction and Henry reaction. In this work, we describe the crystallization of two halogenometallate based on 2-methylimidazole. Their IR, thermal analysis, catalytic properties and antibacterial activities have also been investigated. RESULTS: Two new isostructural organic-inorganic hybrid materials, based on 2-methyl-1H-imidazole, 1 and 2, were synthesized and fully structurally characterized. The analysis of their crystal packing reveals non-covalent interactions, including C/N-H···Cl hydrogen bonds and π···π stacking interactions, to be the main factor governing the supramolecular assembly of the crystalline complexes. The thermal decomposition of the complexes is a mono-stage process, confirmed by the three-dimensional representation of the powder diffraction patterns (TDXD). The catalytic structure exhibited promising activity using MeOH as solvent and as the unique source of acetalization. Moreover, the antimicrobial results suggested that metal-complexes exhibit significant antimicrobial activity. CONCLUSION: This study highlights again the structural and the biological diversities within the field of inorganic-organic hybrids.

17.
Acta Crystallogr Sect E Struct Rep Online ; 70(Pt 2): o204, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24764912

RESUMO

In the crystal structure of the title salt, C7H12N2 (2+)·2NO3 (-), the nitrate ions are located in the vicinity of the protonated amine groups, accepting strong N-H⋯O hydrogen bonds. Each ammonium group is involved in a total of three such inter-actions with neighbouring nitrate ions, generating a three-dimensional network. In addition, there are π-π inter-actions between the aromatic rings of centrosymmetrically related di-ammonium moieties, with a centroid-centroid distance of 3.682 (1) Å.

18.
Inorg Chem ; 53(5): 2619-27, 2014 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-24533651

RESUMO

The synthesis of a series of supramolecular double sulfate salts using transition metals and the aromatic amine α-methylbenzylamine afforded an unexpected hybrid lamellar structure type. (C8H12N)2[M(H2O)4(SO4)2]·2H2O (M = Fe to Zn) crystallizes with a monoclinic structure (S.G. P21/n), with a significant interlamellar distance of more than 16 Å. While comparable to common clay materials, the crystal structure is actually supramolecular; in particular, the mineral layer is built from hydrogen bonds only. The interlayer space is filled with aromatic amines that form chains through C-H···π interactions. The thermal study of all metal compounds revealed good stability of the filled compounds up to 200 °C. The dehydration proceeds differently according to the metal incorporated into the structure. In particular, the stepped release of water drastically modifies the interlayer space, which is able to vary from 14.8 to 18.8 Å, in an opposite way for the Zn-related compound compared to other metals.

19.
Artigo em Inglês | MEDLINE | ID: mdl-24109360

RESUMO

In the title salt, C10H28N4 (4+)·4HSO4 (-), the cation lies about an inversion center. In the crystal, O-H⋯O and N-H⋯O hydrogen bonds connect the anions and cations, forming a three-dimensional network.

20.
Dalton Trans ; 42(2): 399-406, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23059799

RESUMO

A series of double dihydromethylpiperazinediium metallic sulfates 1-7 [H(2)mpz]M(II)(SO(4))(2)·nH(2)O (mpz = 2-methylpiperazine, C(5)H(12)N(2)) are prepared by slow evaporation using a racemic (R/S)-mpz (for 1, 2) or enantiopure R-mpz (for 3), S-mpz (for 4-7) and sulfates of Cu(II) (for 5), Fe(II) (for 1, 4), Co(II) (for 7) and Zn(II) (for 2, 3, 6), and characterized by infrared spectroscopy, elemental analysis and single crystal X-ray diffraction. The [M(II)(H(2)O)(6)](2+), [(R/S)-H(2)mpz](2+), [(R)-H(2)mpz](2+) or [(S)-H(2)mpz](2+) cations and 2SO(4)(2-) anions are linked together via two types of hydrogen bonds, Ow-Hw···O and N-H···O, leading to supramolecular arrangements. The use of the racemic 2-mpz provides alternatives in crystallization: a centrosymmetric structure where the enantiomers are related by an appropriate crystallographic symmetry operation or one where the enantiomers occupy the same crystallographic position, generating disorder. Compounds 1-7 act as diastereoselective catalysts for the nitroaldol (Henry) reaction. The diastereoselectivity can be regulated from exclusive threo to exclusive erythro isomer preparation with typical yields of 50-99%, depending on the catalyst and the substrate used.

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