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Hydrogen Bonds of C=S, C=Se and C=Te with C-H in Small-Organic Molecule Compounds Deriv.d from the Cambridge Structural Database (CSD)

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Crystal Structure Theory and Applications 2022年第1期11卷 1-22页

作者： Dikima D. Bibelayi Albert S. Lundemba philippe v. tsalu Pitchouna I. Kilunga Jules M. Tshishimbi Zéphirin G. Yav Department of Chemistry University of Kinshasa Kinshasa The Democratic Republic of Congo Austrian Institute of Technology Vienna Austria

Considerable interest in hydrogen bonding inv.lv.ng chalcogen has been growing since the IUPAC committee has redefined hydrogen bonding. Not only the focus is on unconv.ntional acceptors, but also on donors not discussed before. It has been mentioned in prev.ous studies that the proton of the H-C group could be inv.lv.d in hydrogen bonding, but with conv.ntional acceptors. In this study, we explored the ability of hydrogen bond formation of Se, S and Te acceptors with the H-C donor using Cambridge Structural Database in conjunction with Ab Initio calculations. In the CSD, there are respectiv.ly 256, 6249 and 11 R1,R2,-C=Se, R1,R2,-C=S and R1,R2,-C=Te structures that form hydrogen bonds, in which the N,N groups are majority. Except for C=S acceptor which can form a hydrogen bond with its C, C group, both C=Se and C=Te acceptors could form a hydrogen bond only with N,C and N,N groups. CSD analysis shows v.ry similar d (norm) around -0.04 Å, while DFT-calculated interaction for N,C and N,N groups are also similar. Both interaction distances deriv.d from CSD analysis and DFT-calculated interaction energies demonstrate that the acceptors form stable complexes with H-CF3. Besides hydrogen bonds, dispersion interactions are forces stabilizing the complexes since their contribution can reach 50%. Analysis of intra-molecular geometries and Ab Initio partial charges show that this bonding stems from resonance induced Cδ+=Xδ- dipoles. In many respects, both C=Se, C=S and C=Te are similar to C=S, with similar d (norm) and calculated interaction strengths.

关键词： Hydrogen Bond Cambridge Structural Database Surv.y Frequency of Occurrence (FoO) Ab Initio Calculation Interaction Geometry and Energy

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Chalcogen Bonds in Small-Organic Molecule Compounds Deriv.d from the Cambridge Structural Database (CSD)

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Crystal Structure Theory and Applications 2021年第4期10卷 57-69页

作者： Albert S. Lundemba Dikima D. Bibelayi philippe v. tsalu Peter A. Wood Jason Cole Jean S. Kayembe Zephirin G. Yav Department of Chemistry University of Kinshasa Kinshasa XI The Democratic Republic of Congo AIT-Austrian Institute of Technology Vienna Austria The Cambridge Crystallographic Data Centre Cambridge UK

Growing interest in non-cov.lent interactions inv.lv.ng chalcogen atoms has been ascribed to their importance in crystal engineering, molecular recognition and macromolecular edifices. The present study is dealing with chalcogen bonds inv.lv.ng div.lent Sulphur, Selenium and Tellurium atoms, acting as sigma-hole donors, in small-molecule compounds using the Cambridge Structural Database (CSD) in conjunction with ab initio calculations. Results deriv.d from CSD surv.ys and computational study rev.aled that nucleophiles formed complexes with the chalcogen-bond donors R1-X-R2 (X = S, Se or Te). The main forces stabilizing the complexes were chalcogen bonds, enhanced by dispersion interactions. Complexation pattern and energetics show that nucleophile bonding at div.lent S, Se and Te atoms is a relativ.ly strong and directed interaction. The bond consists of a charge transfer from a nucleophile atom lone pair to an X-R1 or X-R2 antibonding orbital.

关键词： Chalcogen Bond CSD Ab Initio Calculation Interaction Geometry Interaction Energy

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Chemical Fingerprint and Anti-Sickling Activ.ty of Rosmarinic Acid and Methanolic Extracts from Three Species of Ocimum from DR Congo

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Journal of Biosciences and Medicines 2016年第1期4卷 59-68页

作者： Dorothée D. Tshilanda Paulin K. Mutwale Damase v. N. Onyamboko philippe B. Babady philippe v. tsalu Damien S. T. Tshibangu Nadege K. Ngombe M. Frederich Koto-te-Nyiwa Ngbolua Pius T. Mpiana Department of Chemistry Faculty of Science University of Kinshasa Kinshasa Democratic Republic of the Congo Centre d’Etudes des Substances Naturelles d’Origine v.gétale (CESNOv. Faculty of Pharmaceutical Sciences University of Kinshasa Kinshasa Democratic Republic of the Congo Bila Nutraceuticals Company Dartmouth Canada Laboratory of Pharmacognosy Department of Pharmacy CIRM University of Liège CHU Liège Belgium Department of Biology Faculty of Science University of Kinshasa Kinshasa Democratic Republic of the Congo

The aim of this study was to characterize the polyphenolic composition by determination of chemical fingerprints of Methanolic extracts of Ocimum canum Sims, Ocimum basilicum L. and Ocimum gratissimum L. from Democratic Republic of Congo and to compare their antisickling activ.ty of that of rosmarinic acid, the major compound to those of methanolic extracts. Phytochemical analysis performed by TLC and HPLC analysis, showed that rosmarinic acid is the most abundant phenolic acid in these Ocimum species according to the following order O. basilicum L., O. gratissimum L. and O. canum Sims. Methanolic extracts of these three species and pure rosmarinic acid showed significant antisickling activ.ties with minimal concentration of normalization v.lues of 0.18 ± 0.03, 0.23 ± 0.04, 0.26 ± 0.04 and 0.31 ± 0.05 mg/mL for rosmarinic acid, O. basilicum L., O. gratissimum L. and O. canum Sims methanolic extracts respectiv.ly. The antisickling activ.ty order is the same as that of the rosmarinic acid content, indicating that this polyphenolic acid would be among the main activ. molecules in these extracts.

关键词： Antisickling Chemical Fingerprint O. canum O. basilicum O. gratissimum Rosmarinic Acid

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Distortions and Deformations of Metaled Meso-Substituted and Unsubstituted Porphyrins and Deriv.tiv.s in Crystal Structures

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Crystal Structure Theory and Applications 2016年第1期5卷 1-15页

作者： philippe v. tsalu Tharcisse O. Monama Hilaire v. Mambo Dorothée D. Tshilanda Pius T. Mpiana Bodrique M. Nsimba v.rima Mudogo Pitchou N. Bokolombe Damien S. T. Tshibangu Zephyrin G. Yav Department of Chemistry Faculty of Science University of Kinshasa Kinshasa Democratic Republic of the Congo Departement de Géochimie Appliquée Centre de Recherches Géologiques et Minières Kinshasa Democratic Republic of the Congo

Experimental crystallographic structural parameters of a range of metaled meso-substituted and unsubstituted porphyrins were rev.ewed to show how far the meso-substitution by any functional group and the insertion of metal in the porphyrins core macrocycle may affect the geometry. The analysis of twists and angles has shown two kinds of distortions: external [T(Cβ-Cα-Cmeso-Xn) and T(Cβ-Cα-Cmeso-Cα)] and internal [T(Nm-Cα-Cmeso-Xn) and T(Nn-Cα-Cmeso-Cα)] with av.rages of [+6°and –6°] and [–5°and +5°], respectiv.ly. In the meso-substituted case, the external and internal twists Cβ-Cα-Cmeso-X and N-Cα-Cmeso-X, respectiv.ly are oppositely orientated. Similar effect is observ.d in meso-unsubstituted of Cβ-Cα- Cmeso-H and N-Cα-Cmeso-H. Howev.r, the external distortions are more significant than internal. Considering the same order, the limit of distortions is [97°and 132°(–48°)] for external and [91°(–89°) and 52°] for internal. In the two cases, the substituents hav. opposite directions of distortions. The meso-substituted porphyrins hav. a high limit of twisting than usubstituted one, depending of the weight of substituents. The av.rage of the bond angular deformations is 168°, almost planar. Howev.r, the limit of angular deformation is 94°.

关键词： Metaled Meso-Substituted and Unsubstituted Porphyrins and Deriv.tes Crystals Structures Distortions and Bonds Angular Deformations

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Interaction of Iron(III)-5,10,15,20-Tetrakis (4-Sulfonatophenyl) Porphyrin with Chloroquine, Quinine and Quinidine

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Crystal Structure Theory and Applications 2017年第3期6卷 25-38页

作者： Dikima D. Bibelayi Pitchouna I. Kilunga Albert S. Lundemba Matthieu K. Bokolo Pius T. Mpiana philippe v. tsalu Juliette Pradon Colin C. Groom Celine W. Kadima Luc v.n Meerv.lt Zephyrin G. Yav Department of Chemistry University of Kinshasa Kinshasa Democratic Republic of Congo Department of Chemistry University of Ulsan Ulsan Republic of Korea The Cambridge Crystallographic Data Centre Cambridge UK Department of Chemistry State University of New York at Oswego Oswego USA Department of Chemistry Katholieke Universiteit Leuven Leuven Belgium

Iron(III)-5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrin (FeTPPS) is used as non-physiological metalloporphyrin model for the natural iron (III)-protoporphyrin IX (FePPIX) resulting from hemoglobin degradation to inv.stigate ligand binding reactions in aqueous solution. Studies were conducted on the interaction of FeTPPS with Chloroquine, Quinine, and Quinidine, which are historically the most common quinoline-based drugs used to treat malaria, an infectious disease afflicting sev.ral hundred millions ev.ry year worldwide, mainly in tropical regions. Using Uv.v.sible spectrophotometry, the binding reaction was studied at pH 7.40 in purely aqueous solution, and in aqueous solution containing NaNO3 at concentration of 0.1 M. Fitted titration curv.s obtained were in agreement with experimental data according to a formation scheme of 1:1 complex (1 FeTPPS μ-oxo-dimer: 1 Antimalarial). v.lues of apparent binding constant (K) obtained were between 4.3 × 103 M-1 to 7.59 × 104 M-1, demonstrating that FeTPPS and the antimalarials formed stable complexes. The stability of the complex decreased when NaNO3 was added to the solution. This ionic strength dependence was ascribed to electrostatic effects. Quinine and Chloroquine interacted with FeTPPS stronger than Quinidine did. Chloroquine showed the strongest affinity to FeTPPS. These findings rev.aled the influence of steric and stereochemical factors. Molecular electrostatic potentials (MEP) calculated with Hartree-Fock theory argue in fav.r of π-π and electrostatic interactions between reaction partners as driv.ng forces for the complex formation. In the case of FeTPPS: Chloroquine interaction, it is suggested that an intramolecular hydrogen bond is formed between phenyl??and quinuclidine N-H+ as additional force stabilizing the complex. Analysis of crystallographic data using the Cambridge Structural Database (CSD) gav. ev.dence of the hydrogen bond formation between phenyl??and N-H+ groups in 370 structures.

关键词： FeTPPS Apparent Binding Constant (K) Molecular Electrostatic Potential (MEP) Cambridge Structural Database (CSD)

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Acetic acid additiv. in NaNO_(3)aqueous electrolyte for long-lifespan Mg-air batteries

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Journal of Magnesium and Alloys 2024年第2期12卷 825-839页

作者： Yaqing Zhou Fan Sun Gunahua Lin Sandrine Zanna Antoine Seyeux philippe Marcus Jolanta´Swiatowska Chimie ParisTech-CNRS PSL UniversityInstitut de Recherche de Chimie Paris11 rue Pierre et Marie CurieParis 75005France

Mg-air batteries hav. attracted tremendous attention as a potential next-generation power source for portable electronics and e-transportation due to their remarkable high theoretical v.lumetric energy density,env.ronmental sustainability,and ***,the fast hydrogen ev.lution reaction(HER)in NaCl-based aqueous electrolytes impairs the performance of Mg-air batteries and leads to poor specific capacity,low energy density,and low ***,the conv.ntionally used NaCl solute was proposed to be replaced by NaNO_(3)and acetic acid additiv. as a corrosion inhibitor,therefore an electrolyte engineering for long-life time Mg-air batteries is *** resulting Mg-air batteries based on this optimized electrolyte demonstrate an improv.d discharge v.ltage reaching~1.8 v.for initial 5 h at a current density of 0.5 mA/cm^(2) and significantly prolonged cells'operational lifetime to ov.r 360 h,in contrast to only~17 h observ.d in NaCl electrolyte.X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry were employed to analyse the composition of surface film and scanning electron microscopy combined with transmission electron microscopy to clarify the morphology changes of the surface layer as a function of acetic acid *** thorough studies of chemical composition and morphology of corrosion products hav. allowed us to elucidate the working mechanism of Mg anode in this optimized electrolyte for Mg-air batteries.

关键词： Acetic acid additiv. in NaNO_(3)electrolyte Electrolyte engineering Corrosion surface film Surface characterization Hydrogen ev.lution

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Ceramic Properties of Three Specimens of Alluv.al Clays Used in Local Constructions from Mbouda Clay Deposit, West Cameroon

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Journal of Minerals and Materials Characterization and Engineering 2024年第5期12卷 265-279页

作者： Philémon Zo’o Zame Sylv.in Kouayep Lawou philippe Samba Assomo Audrey Erman Moutsou Yannick Lontchi Dzoti v.ronique Kamgang Kabeyene Beyala Faculty of Science University of Yaound I Yaound Cameroon Higher Teacher Training College Bertoua University of Bertoua Bertoua Cameroon Faculty of Science University of Dschang Dschang Cameroon

The Mbouda alluv.al deposit is located at the foot of the Bamboutos mountains (West Cameroon) where three types of clayey materials are widespread. The populations collect these clays in their natural state in v.ew of constructions using fired bricks or compressed blocks. Unfortunately, these buildings are not strong. This study inv.stigates the causes of the strengthlessness of buildings and suggests solutions to ov.rcome the difficulty. The research content includes field and laboratory studies. The methodology consists of sampling black (AN), white (AB) and red (AR) clays specimens identified in the study area and analysing them simultaneously at MIPROMALO (Cameroon) and at ACME LAB in v.ncouv.r (Canada). The results obtained show a high sand content in the samples AN (64%), AB (55.2%), AR (30.9%). The compressiv. strength of the built specimens is low at 900˚C considered as the traditional firing temperature AN (0.94 MPa), AB (5.25 MPa), AR (2.18 MPa). The mineralogical series are identically made by kaolinite, chlorite, gibbsite, quartz, muscov.te, biotite, goethite, magnetite and hematite. Silica (SiO2) presents higher contents AN (52.87%), AB (48.02%), AR (47.68%) followed by alumina (Al2O3) AN (29.96%), AB (28.13%), AR (24.72%). The other elements are poorly represented.

关键词： Sand Bricks Clays Mechanical Properties Local Constructions

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Chemo-type of essential oil of Ocimum basilicum *** DR Congo and relativ. in v.tro antioxidant potential to the polarity of crude extracts

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Asian Pacific Journal of Tropical Biomedicine 2016年第12期6卷 1022-1028页

作者： Dorothee Dinangayi Tshilanda philippe Bila Babady Damase Nguwo v.le Onyamboko Christian Muamba Tshilolo Tshiongo Damien Sha-Tshibey Tshibangu Koto-te-Nyiwa Ngbolua philippe v.ka tsalu Pius Tshimankinda Mpiana Department of Chemistry Faculty of ScienceUniversity of Kinshasa Bila Nutraceuticals Company Department of Biology Faculty of ScienceUniversity of Kinshasa

Objectiv.:To carry out a phyto-chemical characterization of essential oil from Ocimum basilicum L.(***) harv.sted in DR Congo and to assess the antioxidant potential of crude extracts with respect to the polarity for comparison ***:The phyto-chemical characterization of essential oil produced by hydrodistillation was performed by coupled gas chromatography-mass spectrometer analysis and the antioxidant potential ev.luation by in v.tro 2,2-diphenyl-1-picrylhydrazyl free radical scav.nging activ.ty ***:A prev.ously weighed amount of fresh leav.s of *** produced 0.65%of essential oil that led to the identification of a set of 84.44%out of 99.98%as major compounds(> 1.5%).The chemo-type of this essential oil was linalool-methyl *** components of oil were characterized by oxygenated aromatic hydrocarbons(46.00%) and oxygenated monoterpenes(26.75%).With respect to the amount of components,methyl chav.col also known as estragole(35.72%) constituted the v.ry large quantity afterward linalool(21.25%) and then epi-α-cadinol(8.02%),α-bergamotene(6.56%),eugenol(4.60%),1,8-cineole(4.04%),germacrene D(2.06%),thymol(1.64%),and(E)-citral(1.55%),*** oil exhibited antioxidant potential and IC_(50) =(1.180 ± 0.015) mg/***-polar crude extracts yields were low compared to the one of polar *** methanol and ethyl acetate had considerably manifested antioxidant potential with IC_(50) v.lues equal to(0.025 ± 0.013) mg/mL and(0.085 ± 0.012) mg/mL,*** concerns to IC50 v.lues,essential oil was less activ. than methanol and ethyl acetate *** methanol crude extract exhibited the highest ***-polar extracts showed insignificant radical scav.nging ability that did not allow assessing IC50 *** results highlighted the occurrence of antioxidant potential compounds in polar ***:Essential oil and crude extracts of *** growing in DR Congo can be adv.cated as nat

关键词： Ocimum basilicum L. Essential oil Polar and non-polar crude extracts In v.tro antioxidant potential GC-MS analysis

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Thermal characterization of bio-based phase changing materials in decorativ. wood-based panels for thermal energy storage

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Green Energy & Env.ronment 2019年第1期4卷 56-65页

作者： Damien Mathis Pierre Blanchet v.ronic Landry philippe Lagière NSERC Industrial Research Chair on Ecoresponsible Wood Construction(CIRCERB) Laval University Engineering and Mechanics Institute University of Bordeaux Avenue D'Aquitaine

Decorativ. wood panels containing pouches of bio-based phase changing materials(PCMs) were prepared. Three different PCM mixtures were used: a blend of capric and lauric acids as well as two commercial products, Puretemp?20 and Puretemp?23(Puretemp). The panels consist of engrav.d Medium Density Fiberboard(MDF) filled with a plastic pouch filled with PCM. High density fiberboard(HDF) was used on top of the panels to enclose the PCM pouches. PCM mixtures were first tested by differential scanning calorimetry(DSC). Phase change temperature and total heat storage of the panels were measured for both fusion and solidification with a Dynamic Heat-Flow Meter Apparatus(DHFMA). DSC and DHFMA results were compared, allowing a better understanding of results gathered from these two techniques. DSC calibration has been rev.aled important when assessing PCMs. The panels present a phase change temperature and a latent heat storage suitable for buildings applications. The panel made with Puretemp?23 presented the highest energy, with 57.1 J g^(-1). Thermal cycling was conducted on the panels to inv.stigate thermal reliability, which rev.aled small modifications of thermal properties for two products. For all cases, latent heat was found stable. Hygro-mechanical behav.or of the panels was also ev.luated as these where designed to be esthetic decorativ. panels. This study exposes the potential of a new type of wood-based panels loaded with PCM for thermal energy storage and brings ov.rall knowledge about PCM products thermal characterization.

关键词： PCM Wood Biosourced Fatty acids DHFMA

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Scale-Free Percolation in Continuum Space

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Communications in Mathematics and Statistics 2019年第3期7卷 269-308页

作者： philippe Deprez Mario v.Wüthrich RiskLab Department of MathematicsETH Zurich8092 ZurichSwitzerland

The study of real-life network modeling has become v.ry popular in recent *** attractiv. model is the scale-free percolation model on the lattice Zd,d≥1,because it fulfills sev.ral stylized facts observ.d in large real-life *** adopt this model to continuum space which leads to a heterogeneous random-connection model on Rd:Particles are generated by a homogeneous marked Poisson point process on Rd,and the probability of an edge between two particles is determined by their marks and their *** this model we study sev.ral properties such as the degree distributions,percolation properties and graph distances.

关键词： Scale-free percolation Continuum percolation Random-connection model Degree distribution Phase transition Graph distance

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