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1.
Pak J Med Sci ; 40(7): 1332-1337, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39092050

RESUMO

Objective: To evaluate the clinical efficacy of novel titania-nanoparticle reinforced bonding agent on post-restorative sensitivity in patients. Methods: This triple-blinded, randomized clinical trial included participants (n = 60) having Class- I and II cavitations with a minimum cavity depth of 3mm at Department of Operative Dentistry & Endodontics, School of Dentistry, Shaheed Zulfiqar Ali Bhutto Medical University, Islamabad from January 5, 2023, to June 20, 2023. They were randomly assigned into two groups A and B (n = 30). After informed consent, restorative intervention was accomplished using an etch-and-rinse adhesive strategy. In Group-A, titania-nanoparticle-incorporated bonding agent was used for composite restoration, while in Group-B, bonding agent without nanoparticles was used. The primary outcome was assessed using Visual Analogue Scale mean score. Participants were instructed to rate their sensitivity status at follow-ups: 24 hours, one week, and one month. Mann-Whitney U test was employed to compare sensitivity between the two groups. Results: According to results of this trial, a significant difference was observed between two groups after 24 hours (p = 0.004) and one week (p = 0.002). However, no discernible difference was observed after one month (p = 0.643). Conclusion: Post-restorative sensitivity in patients with composite restorations was reduced using titania-reinforced bonding agents as compared to bonding agents without nanoparticles. This shows that inclusion of titania nanoparticles into adhesive dentistry could be beneficial in resolving post-restorative sensitivity occurring with composite restorations.

2.
J Esthet Restor Dent ; 2024 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-39095872

RESUMO

OBJECTIVE: This clinical study aimed to evaluate the difference in the time of application phase, employing the conventional and modified direct orthodontic bonding method. MATERIALS AND METHODS: Thirty patients who needed orthodontic therapy with fixed appliances were randomly divided into two equal groups (n = 15): the control and experimental group, according to the bonding method applied. A total of 600 metal brackets inch slot 0.022 (Mini Sprint®, Forestadent, Germany) were bonded to incisors, canines, and premolars using the light-cured adhesive Transbond XT (3M Unitek, Monrovia, CA, USA). The failure rates of the brackets were evaluated within 12 months. The independent samples t-test was applied. The Chi-square test and Fisher exact test were used for statistical analysis. RESULTS: The initial bonding time using the modified method was significantly shorter (3.27 min or 17.1% per patient) compared with the conventional bonding method (p < 0.001). Number of failed brackets between the two methods did not differ significantly (p = 0.226). CONCLUSION: The time of the application phase in initial bonding using the modified method (experimental group) was shorter than in control group. There was no statistically significant difference in the number of bond failures between the two methods. CLINICAL SIGNIFICANCE: The modified application phase of direct orthodontic bracket placement shortens the total bonding time and facilitates the manual work of orthodontists.

3.
Artigo em Inglês | MEDLINE | ID: mdl-39087622

RESUMO

Most natural supporting tissues possess both exceptional mechanical strength, a significant amount of water, and the anisotropic structure, as well as nanoscale assembly. These properties are essential for biological processes, but have been challenging to emulate in synthetic materials. In an effort to achieve simultaneous improvement of these trade-off features, a hydrogen bonding-induced self-assembly strategy was introduced to create nanoporous plastic-like polymer hydrogels. Multiple hydrogen bonding-mediated networks and nanoporous orientation structures endow transparent hydrogels with remarkable mechanical robustness. They exhibit Young's modulus of up to 223.7 MPa and a breaking strength of up to 10.3 MPa, which are superior to those of most common polymer hydrogels. The uniform porous nanostructures of hydrogen-bonded hydrogels contribute to a significantly larger specific surface area compared to conventional hydrogels. This allows for the retention of high mechanical properties in environments with a high water content of 70 wt %. A rubbery stage is observed during the heating process, which can reverse and reshape the manufacture of objects with various desired 2D or 3D shapes using techniques such as origami and kirigami. Finally, as a proof-of-concept, the outstanding mechanical properties of poly(MAA-co-AA-co-NVCL) hydrogel, combined with its high water content, make it suitable for applications such as smart temperature monitors, multilevel information anticounterfeiting, and artificial muscles.

4.
Acad Pediatr ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39097000

RESUMO

OBJECTIVES: Given that infant development is influenced by caregiver mental health, we tested whether an intervention to reduce antenatal anxiety could affect infant development. A secondary aim was to test depressive symptoms, maternal responsiveness, and maternal infant bonding as mediators of this relationship. METHODS: Between 2020 and 2022, pregnant women participated in a randomized controlled trial of the Happy Mother-Healthy Baby (HMHB) program based on cognitive behavioral therapy. We collected data on child development from 202 intervention and 198 control participants in a public hospital in Pakistan. Child development was measured using the Ages and Stages Questionnaires-Version 3 at six weeks postpartum. Using intent-to-treat analyses, we examined whether the intervention was associated with performance on the five ASQ-3 domains. Causal mediation analysis was used to assess depressive symptoms, bonding, and maternal-infant responsiveness as mediators. RESULTS: Socio-demographic characteristics were evenly distributed between study arms. Intervention arm infants showed a 2.1-point increase (95% CI: 0.12, 4.17) in communication scores compared to controls. Though not achieving statistical significance, intervention infants also showed a 2.0-point increase (95% CI:-0.06, 4.09) in gross motor development performance. Bonding, depression, and responsiveness were mediators between the intervention and infant communication (Bindirect=1.94 (95%CI: 0.86, 3.25) depression; Bindirect=0.57 (95% CI: 0.09, 1.16) bonding; Bindirect=0.53 (95% CI: 0.01, 1.21) responsiveness; and Bindirect=1.94 (95%CI: 0.86, 3.25). Bonding, responsiveness, and depression mediated 25%, 23%, and 87% of the total association, respectively. CONCLUSIONS: HMHB positively affected infant communication at six-week follow-up. Larger studies with longer follow-up are needed to confirm and extend these findings. TRIAL REGISTRATION: ClinicalTrials.gov NCT03880032; https://clinicaltrials.gov/ct2/show/NCT03880032.

5.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 8): 845-851, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39108778

RESUMO

Two new [1-(phenyl-sulfon-yl)-1H-indol-2-yl]methanamine derivatives, namely, N-(3-meth-oxy-phen-yl)-N-{[1-(phenyl-sulfon-yl)-1H-indol-2-yl]meth-yl}acetamide, C24H22N2O4S, (I), and N-(2,5-di-meth-oxy-phen-yl)-N-{[1-(phenyl-sulfon-yl)-1H-indol-2-yl]meth-yl}benzene-sulfonamide, C29H26N2O6S2, (II), reveal a nearly orthogonal orientation of their indole ring systems and sulfonyl-bound phenyl rings. The sulfonyl moieties adopt the anti-periplanar conformation. For both compounds, the crystal packing is dominated by C-H⋯O bonding [C⋯O = 3.312 (4)-3.788 (8) Å], with the structure of II exhibiting a larger number, but weaker bonds of this type. Slipped π-π inter-actions of anti-parallel indole systems are specific for I, whereas the structure of II delivers two kinds of C-H⋯π inter-actions at both axial sides of the indole moiety. These findings agree with the results of Hirshfeld surface analysis. The primary contributions to the surface areas are associated with the contacts involving H atoms. Although II manifests a larger fraction of the O⋯H/H⋯O contacts (25.8 versus 22.4%), most of them are relatively distal and agree with the corresponding van der Waals separations.

6.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 8): 878-881, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39108780

RESUMO

This title compound, C20H26O2, was isolated from the benzene fraction of the stem bark of Staudtia kamerunensis Warb. (Myristicaceae) using column chromatography techniques over silica gel. The compound was fully characterized by single-crystal X-ray diffraction, one and two-dimensional NMR spectroscopy, IR and MS spectrometry. The compound has two fused cyclo-hexane rings attached to a benzene ring, with a carb-oxy-lic acid on C-4. This cyclo-hexene ring has a chair conformation while the other adopts a half-chair conformation. The benzene ring is substituted with a propenyl moiety. The structure is characterized by inter-molecular O-H⋯O hydrogen bonds, two C-H⋯O intra-molecular hydrogen bonds and two C-H⋯π inter-actions. The mol-ecular structure confirms previous studies carried out by spectroscopic techniques.

7.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 8): 816-819, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39108786

RESUMO

The reaction of cadmium iodide with 3-amino-pyrazole (3-apz) in ethano-lic solution leads to tautomerization of the ligand and the formation of crystals of the title compound, catena-poly[[di-iodido-cadmium(II)]-bis-(µ-3-amino-1H-pyrazole)-κ2 N 2:N 3;κ2 N 3:N 2], [CdI2(C3H5N3)2] n or [CdI2(3-apz)2] n . Its asymmetric unit consists of a half of a Cd2+ cation, an iodide anion and a 3-apz mol-ecule. The Cd2+ cations are coordinated by two iodide anions and two 3-apz ligands, generating trans-CdN4I2 octa-hedra, which are linked into chains by pairs of the bridging ligands. In the crystal, the ligand mol-ecules and iodide anions of neighboring chains are linked through inter-chain hydrogen bonds into a di-periodic network. The inter-molecular contacts were qu-anti-fied using Hirshfeld surface analysis and two-dimensional fingerprint plots, revealing the relative qu-anti-tative contributions of the weak inter-molecular contacts.

8.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 8): 852-856, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39108784

RESUMO

In the title complex, [U(C10H7N3O3)O2(CH3OH)] n , the UVI cation has a typical penta-gonal-bipyramidal environment with the equatorial plane defined by one N and two O atoms of one doubly deprotonated 2-[5-(2-hy-droxy-phen-yl)-1H-1,2,4-triazol-3-yl]acetic acid ligand, a carboxyl-ate O atom of the symmetry-related ligand and the O atom of the methanol mol-ecule [U-N/Oeq 2.256 (4)-2.504 (5) Å]. The axial positions are occupied by two oxide O atoms. The equatorial atoms are almost coplanar, with the largest deviation from the mean plane being 0.121 Šfor one of the O atoms. The benzene and triazole rings of the tetra-dentate chelating-bridging ligand are twisted by approximately 21.6 (2)° with respect to each other. The carboxyl-ate group of the ligand bridges two uranyl cations, forming a neutral zigzag chain reinforced by a strong O-H⋯O hydrogen bond. In the crystal, adjacent chains are linked into two-dimensional sheets parallel to the ac plane by C/N-H⋯N/O hydrogen bonding and π-π inter-actions. Further weak C-H⋯O contacts consolidate the three-dimensional supra-molecular architecture. In the solid state, the compound shows a broad medium intensity LMCT transition centred around 463 nm, which is responsible for its red colour.

9.
Beilstein J Org Chem ; 20: 1785-1793, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39109295

RESUMO

The ability to investigate hypervalent iodine(V) fluorides has been limited primarily by their difficult preparation traditionally using harsh fluorinating reagents such as trifluoromethyl hypofluorite and bromine trifluoride. Here, we report a mild and efficient route using Selectfluor to deliver hypervalent iodine(V) fluorides in good isolated yields (72-90%). Stability studies revealed that bicyclic difluoro(aryl)-λ5-iodane 6 was much more stable in acetonitrile-d 3 than in chloroform-d 1, presumably due to acetonitrile coordinating to the iodine(V) centre and stabilising it via halogen bonding.

10.
Qual Health Res ; : 10497323241266750, 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39110147

RESUMO

Phenylketonuria (PKU) is a rare metabolic condition characterised by an inability to metabolise phenylalanine (Phe), found in many foods. When pregnant with PKU, women must adhere to a strict low-Phe diet. If they do not, foetal abnormalities or pregnancy loss can occur. Pregnancies are therefore closely clinically monitored and dominated by dietary management, leaving little "space" for women's emotional experience. This article explores the emotional impact of PKU during pregnancy and how this effects pre-natal bonding. Based on interviews with six women with PKU, conducted whilst they were pregnant, this article explores their unusual and previously undocumented experience. Image-making during interviews allowed women to uncover aspects of their experience that might otherwise have remained hidden. Interpretative phenomenological analysis of the transcripts and images generated five themes summarising the women's experiences. Some themes reiterated findings from previous studies, for example, the huge cognitive burden associated with PKU pregnancies and the importance of both expert and informal support to successful pregnancy management. However, new understanding also emerged, including rich description of the emotional load of these pregnancies and strategies that women use to manage this. Anxiety about baby safety was central to their experiences, and the effect of this on pre-natal bonding was explored. This article calls for increased formal and informal support for women with the emotional aspects of their PKU pregnancies, for example, the creation of "attachment-aware" services that support women with their anxiety, promoting strong pre-natal attachment and subsequently protecting maternal and infant mental health throughout pregnancy and beyond.

11.
Front Dent ; 21: 24, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39104788

RESUMO

Objectives: This study aimed to investigate the effect of different reinforcement techniques on the push-out bond strength of fiber posts to over-flared root canals. Materials and Methods: Forty-eight extracted human single-canal premolars were endodontically treated, over-flared, and randomly divided into four groups (N=12) including SARC: luting with self-adhesive resin cement, DCC: luting with dual-cure core build-up resin composite, CRR: relining root canal walls with bulk-fill resin composite, and DAP: relining fiber post with bulk-fill resin composite. After 24 hours, the roots were sectioned to obtain three cervical, middle, and apical 3mm slices. The push-out test was performed and failure pattern was examined. Kruskal-Wallis and post-hoc Dunn-Bonferroni tests were used for statistical analysis (P<0.05). Results: In all three regions, the lowest and highest bond strength was found in the SARC and DAP groups, respectively. In the middle region, there was a statistically significant difference between the bond strength of the SARC group and that of the DCC (P=0.044), CRR (P=0.021), and DAP (P<0.001) groups. There was no significant difference in the apical region. The lowest bond strength was observed in the apical region, and the highest was related to the cervical region. Adhesive failure was the most common failure pattern in all groups. Conclusion: Based on our results DCC, CRR and DAP methods increased bond strength in the middle and cervical sections of over-flared root regions. Considering that DCC is the easiest and most practical method, we propose that CRR and DAP can be replaced with this method in clinical procedures.

12.
Cureus ; 16(8): e66210, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39105206

RESUMO

BACKGROUND: Enamel conditioning with 37% phosphoric acid is the most common technique during orthodontic bracket bonding procedures. However, due to the repeated de-bonding of the orthodontic brackets during treatment, other methods were needed to condition the enamel surface and increase the bond strength. This study aimed to compare the effect of conditioning the enamel surface by sandblasting with aluminum oxide particles or 5.25% sodium hypochlorite gel in combination with acid etching compared to acid etching alone on shear bond strength (SBS). MATERIAL AND METHODS: One hundred eight extracted upper premolars were randomly divided into three groups according to the conditioning enamel surface method. After the first and second bonding of metal brackets, new metal brackets were bonded with a total-etching adhesive after enamel conditioning using different methods: acid etching only (37% phosphoric acid for 30 seconds) (AE group), sodium hypochlorite associated with acid etching (5.25% NaOCl gel for 60 seconds and then acid etching for 30 seconds) (NaOCl-AE group), and sandblasting associated with acid etching (sandblasting for five seconds and then acid etching for 30 seconds) (SB-AE group). The shear bond strengths of the brackets were tested with a universal testing machine. One-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) tests were used to detect significant differences in shear bond strength among groups at the third bonding. Repeated-measure ANOVA and Bonferroni's tests were used to detect significant differences in shear bond strength among the bonding attempts within each group. RESULTS: 5.25% sodium hypochlorite associated with the acid etching method produced significantly greater shear bond strength than sandblasting associated with acid etching and acid etching only methods at the third bonding (16.40 ± 5.80 MPa, 13.60.47 ± 6.40 MPa, and 9.90 ± 4.40 MPa, respectively; P < 0.001). However, there was no significant difference between the AE and SB-AE groups (P = 0.247). In addition, we found a significant decrease in the shear bond strength within each group after each bonding attempt. CONCLUSION: Conditioning the enamel surface with 5.25% sodium hypochlorite associated with acid etching produced greater bond strength than conditioning by sandblasting associated with acid etching and acid etching only at the third bonding. The bond strength of the metal bracket decreased with increasing bonding attempts, even with the application of enamel surface conditioning methods.

13.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124900, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39098294

RESUMO

The atmospheric partitioning of trifluoroacetic acid (TFA) in aerosol is a complex function of the size of suspended water droplets and their pH value. The unraveling of the affinity of TFA towards basic but not acidic conditions may be accomplished by providing an insight into the hydration pattern of undissociated TFA. Owing to rather scarce details on very dilute aqueous solutions of trifluoroacetic acid (TFA), we examined CF3COOD and CF3COONa solutions in D2O in the concentration range 0.001-0.1 mol dm-3 using transmission FTIR spectroscopy and computational methods. Besides detecting the signals originated from undissociated species in both CF3COOD (1787 cm-1 and 1766 cm-1 at c0 = 0.1 mol dm-3) and CF3COONa (1807 cm-1 at c0 = 0.1 mol dm-3) D2O solutions, through computational techniques we identified different TFA hydrates that contribute to the complexity of the spectral appearance. The combination of experimental and computational data suggested the concentration dependence of the predominant hydrogen bonding pattern of TFA. The results obtained in this work should help in understanding the partitioning of TFA into micron-size water droplets in the atmosphere in molecular and structural terms, i.e. the eventual stability of a hydrated complex for a particular TFA conformer.

14.
Small ; : e2400671, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-39101624

RESUMO

Brain lipidic peroxidation is closely associated with the pathophysiology of various psychiatric diseases including depression. Malondialdehyde (MDA), a reactive aldehyde produced in lipid region, serves as a crucial biomarker for lipid peroxidation. However, techniques enabling real-time detection of MDA are still lacking due to the inherent trade-off between recognition dynamics and robustness. Inspired by the structure of phospholipid bilayers, amphiphilic carbon dots named as CG-CDs targeted to cell membrane are designed for real-time monitoring of MDA fluctuations. The design principle relies on the synergy of dynamic hydrogen bonding recognition and cell membrane targetability. The latter facilitates the insertion of CG-CDs into lipid regions and provides a hydrophobic environment to stabilize the labile hydrogen bonding between CG-CDs and MDA. As a result, recognition robustness and dynamics are simultaneously achieved for CG-CDs/MDA, allowing for in situ visualization of MDA kinetics in cell membrane due to the instant response (<5 s), high sensitivity (9-fold fluorescence enhancement), intrinsic reversibility (fluorescence on/off), and superior selectivity. Subsequently, CG-CDs are explored to visualize nerve cell membrane impairment in depression models of living cells and zebrafish, unveiling the extensive heterogeneity of the lipid peroxidation process and indicating a positive correlation between MDA levels and depression.

15.
Chempluschem ; : e202400405, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39104329

RESUMO

Carbon dioxide (CO2) is one of the most abundant greenhouse gases in Earth's atmosphere and responsible for global warming. Therefore, aerial CO2 capture and sequestration has become a major task for human community. Though several adsorbents for CO2 including activated carbon, zeolites, metal-organic frameworks (MOFs), and other surface-modified porous materials are well developed, the supramolecular approaches using synthetic hydrogen-bonding receptors are less explored. This review article highlights the synthetic development of various artificial receptors and their properties toward fixation of aerial CO2 as carbonate (CO32-), bicarbonate (HCO3-), or carbamate (-NHCOO-/>NCOO-) ions, induced by excess fluoride (F-) or hydroxide (OH-) ions as their tetrabutylammonium salts. The utilization of encapsulated carbonate/bicarbonate/carbamate complexes in anion exchange metathesis for separation of oxyanions from aqueous solutions are also discussed. In addition, the release of CO2 and regeneration of receptor molecules are described in a number of occasions. Most importantly, the formation of anion complexes as crystalline materials in solid-state is described in terms of supramolecular chemistry and correlated with their solution-state properties. Finally, the types of receptors containing various functional groups are scrutinized in CO2 uptake, storage, and release processes and hints of endeavours for future research are delineated.

16.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 7): 800-805, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38974147

RESUMO

The crystal structures of 4-benzyl-1H-pyrazole (C10H10N2, 1) and 3,5-di-amino-4-benzyl-1H-pyrazole (C10H12N4, 2) were measured at 150 K. Although its different conformers and atropenanti-omers easily inter-convert in solution by annular tautomerism and/or rotation of the benzyl substituent around the C(pyrazole)-C(CH2) single bond (as revealed by 1H NMR spectroscopy), 1 crystallizes in the non-centrosymmetric space group P21. Within its crystal structure, the pyrazole and phenyl aromatic moieties are organized into alternating bilayers. Both pyrazole and phenyl layers consist of aromatic rings stacked into columns in two orthogonal directions. Within the pyrazole layer, the pyrazole rings form parallel catemers by N-H⋯N hydrogen bonding. Compound 2 adopts a similar bilayer structure, albeit in the centrosymmetric space group P21/c, with pyrazole N-H protons as donors in N-H⋯π hydrogen bonds with neighboring pyrazole rings, and NH2 protons as donors in N-H⋯N hydrogen bonds with adjacent pyrazoles and other NH2 moieties. The crystal structures and supra-molecular features of 1 and 2 are contrasted with the two known structures of their analogs, 3,5-dimethyl-4-benzyl-1H-pyrazole and 3,5-diphenyl-4-benzyl-1H-pyrazole.

17.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 7): 695-698, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38974157

RESUMO

The crystal structures of 2-[1'-(carb-oxy-meth-yl)-4,4'-bi-pyridine-1,1'-diium-1-yl]acetate tetra-fluoro-borate, C14H13N2O4 +·BF4 - or (Hbcbpy)(BF4), and neutral 1,1'-bis-(carboxyl-atometh-yl)-4,4'-bi-pyridine-1,1'-diium (bcbpy), C14H20N2O8, are reported. The asymmetric unit of the (Hbcbpy)(BF4) consists of a Hbcbpy+ monocation, a BF4 - anion, and one-half of a water mol-ecule. The BF4 - anion is disordered. Two pyridinium rings of the Hbcbpy+ monocation are twisted at a torsion angle of 30.3 (2)° with respect to each other. The Hbcbpy monocation contains a carb-oxy-lic acid group and a deprotonated carboxyl-ate group. Both groups exhibit both a long and a short C-O bond. The cations are linked by inter-molecular hydrogen-bonding inter-actions between the carb-oxy-lic acid and the deprotonated carboxyl-ate group to give one-dimensional zigzag chains. The asymmetric unit of the neutral bcbpy consists of one-half of the bcbpy and two water mol-ecules. In contrast to the Hbcbpy+ monocation, the neutral bcbpy mol-ecule contains two pyridinium rings that are coplanar with each other and a carboxyl-ate group with similar C-O bond lengths. The mol-ecules are connected by inter-molecular hydrogen-bonding inter-actions between water mol-ecules and carboxyl-ate groups, forming a three-dimensional hydrogen-bonding network.

18.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 7): 751-754, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38974156

RESUMO

The structure of polymeric catena-poly[2-amino-benzimidazolium [[dioxidovanadium(V)]-µ-oxido]], {(C7H8N3)2[V2O6]} n , has monoclinic symmetry. The title compound is of inter-est with respect to anti-cancer activity. In the crystal structure, infinite linear zigzag vanadate (V2O6)2- chains, constructed from corner-sharing VO4 tetra-hedra and that run parallel to the a axis, are present. Two different protonated 2-amino-benzimidazole mol-ecules are located between the (V2O6)2- chains and form classical N-H⋯O hydrogen bonds with the vanadate oxygen atoms, which contribute to the cohesion of the structure.

19.
Acta Crystallogr E Crystallogr Commun ; 80(Pt 7): 763-766, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38974163

RESUMO

The crystal structure of 1,2,3,4-tetra-hydro-isoquinolin-2-ium (2S,3S)-3-carb-oxy-2,3-di-hydroxy-propano-ate monohydrate, C9H12N+·C4H5O6 -·H2O, at 115 K shows ortho-rhom-bic symmetry (space group P212121). The hydrogen tartrate anions and solvent water mol-ecules form an intricate diperiodic O-H⋯O hydrogen-bond network parallel to (001). The tetra-hydro-isoquinolinium cations are tethered to the anionic hydrogen-bonded layers through N-H⋯O hydrogen bonds. The crystal packing in the third direction is achieved through van der Waals contacts between the hydro-carbon tails of the tetra-hydro-isoquinolinium cations, resulting in hydro-phobic and hydro-philic regions in the crystal structure.

20.
IUCrdata ; 9(Pt 6): x240620, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38974850

RESUMO

The title compound, [Fe(C4H8O)4(H2O)2][Fe4Ga4(C2H6O2Si)Cl4(CO)15]·4C4H8O, consists of an iron(II) cation octa-hedrally coordinated by two water mol-ecules (trans) with four tetra-hydro-furans (THF) at equatorial sites. Two additional THF mol-ecules are hydrogen bonded to each of the water mol-ecules. The dianion of the title compound is an organometallic butterfly complex with a dimethyl siloxane core and two iron-gallium fragments. The lengths of the iron to gallium metal-metal bonds range from 2.3875 (6) to 2.4912 (6) Å.

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