CRYSTENGCOMM
·
2021
·Vol. 24
·期 1
·95-106
·
IF 3.545
Yunping Zhoujin,Yang Tao,Panpan Zhou,Sean Parkin,Tonglei Li,Ju Guo,Faquan Yu,Sihui Long
Addition of methyl group(s) to either or both aromatic rings of fenamic acid (FA) afforded three FA derivatives (1–3), designed to investigate the effect on the polymorphic behavior of these compounds exerted by substitution. A relatively comprehensive polymorph screen led to the discovery of four polymorphs for compound 3, for which substitution took place on both aromatic rings, in contrast to the production of either two or one form(s) for compounds 1 and 2, both of which are mono-substituted. The observation indicated that both substitution position and pattern are important in the polymorphism of these compounds. The thermal properties of each system were investigated by differential scanning calorimetry (DSC). Conformational scans and Hirshfeld surface analyses were performed to study the mechanism of polymorphism and the intermolecular interactions contributing to the stability of each crystal form.
研究领域:
药物化学
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晶体学
·
材料科学
✓ 已验证
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2022
·
IF 4.01
Yunping Zhoujin,Yuping Li,Peng-Yu Liang,Pan-Pan Zhou,Sean Parkin,Tonglei Li,Faquan Yu,Sihui Long
A series of homologues (1–4) of fenamic acid have been synthesized by varying the length of the linker between the two aromatic rings, and their polymorphism has been investigated. Under the same crystallization conditions, each of the newly synthesized compounds leads to two forms, except for compound 1, which indicates that additional flexibility due to homologation does not necessarily lead to more polymorphs. The molecules in each polymorphic system show different conformations due to the rotation about specific sigma bonds. Phase transitions are observed between the polymorphs of each system. Conformational analysis and Hirshfeld surface analysis were applied to investigate the effect of conformational flexibility on the polymorphism of these compounds.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2018
·
IF 3.649
Somboon Chaemchuen,Kui Zhou,Mekhman S. Yusubov,Pavel S. Postnikov,Nikom Klomkliang,Francis Verpoort
A first time report on a solid-state polymorphic transformation of MOF materials [Zn 2 (bdc) 2 (dabco)] n (ZnBD) and [Co 2 (bdc) 2 (dabco)] n (CoBD) from a pillared kagomé-lattice form (ZnBD kgm or CoBD kgm ) to a pillared square-lattice form (ZnBD sql or CoBD sql ) at ambient condition is given. Several solvents were applied as a guest-driven molecule to trigger the solid-to-solid transformation while only methanol demonstrated to be able to perform this transformation. The methanol-driven solid-state transformation behavior was observed by using powder X-ray diffraction. The morphology investigated that the rod-like Kagomé form rapidly transformed into a tubular square lattice upon addition of methanol at room temperature. The characteristic porosity reconfirmed the transformation was complete. A transformation mechanism of disconnection-deformation-rebuilding was elucidated based on the experiment.
研究领域:
材料科学
·
化学
✓ 已验证
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2020
·
IF 4.089
Wei Du,Huifen Wang,Runpu Wang,Xuemin Wang,Penggao Cheng,Jianping Zhang,Na Tang,Liang Zhu,Penglei Cui
To further understand the relationship among molecular conformational flexibility, thermodynamics, nucleation, and the polymorphic outcomes, the homogeneous nucleation and heterogeneous nucleation from fast cooling crystallization, evaporative crystallization, antisolvent crystallization, and solution-mediated polymorphic transformation were studied, considering the effects of temperature, supersaturation, and solvent. The conformers can rapidly fluctuate in solution with either monomers solvated by solvent molecules or carboxylic acid dimers and stacked dimers. No links between conformational flexibility and polymorphic outcome were found from both the experiment results and DFT calculation, though conformational polymorphs were obtained during the crystallization of 4-hexyloxybenzoic acid (HOBA). The stability relationship of HOBA polymorphs was confirmed, and the desolvation process was found to play a vital role in the overall self-assembly during crystallization. Finally, a process-control chart to prepare different polymorphs of HOBA was drawn to summarize the polymorphic differences caused by conformation.
研究领域:
物理化学
·
材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2011
·
IF 1.599
Bin Peng,Yong Nie,Jinling Miao,Zhenwei Zhang,Meiling Xu,Guoxin Sun
The reaction of o -carboranyllithium with two equiv. of 2-pyridinecarboxaldehyde affords 1-[(hydroxy)(pyridyl)methyl]- o -carborane ( 1 ) and 1,2-bis[(hydroxy)(pyridyl)methyl]- o -carborane ( 2 ), which have been characterized by IR and NMR spectroscopy, mass spectrometry and single-crystal X-ray diffraction. Compound 2 exhibits interesting polymorphism (monoclinic 2a and triclinic 2b ). The solid state structures of the new carboranes feature intermolecular and intramolecular hydrogen bonding interactions involving all the N and O atoms, leading to one dimensional ( 1 , 2b ) or two-dimensional ( 2a ) supramolecular structures. The photoluminescence of 1 and 2b was investigated in the solid and solution states at room temperature, respectively.
研究领域:
化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CRYSTAL GROWTH & DESIGN
·
2019
·
IF 4.153
Yuting Liu,Mingtao Zhang,Danrui Xu,Sean Parkin,Tonglei Li,Conggang Li,Zhaoyong Yang,Faquan Yu,Sihui Long
To probe the effect of substituent size and isomerization on the polymorphism of fenamic acid (FA) derivatives, we synthesized two FA analogues, namely, 2-(naphthalen-1-ylamino)-benzoic acid and 2-(naphthalen-2-ylamino)-benzoic acid (NBAs), and investigated their polymorphism. Contrary to the lack of polymorphism in FA, we discovered two crystal forms (1-I, 1-II, 2-I, and 2-II) for each of the two compounds. We characterized the two polymorphic systems with single-crystal X-ray diffraction, powder X-ray diffraction, and infrared and Raman spectroscopy, and observed certain structural similarities between 1-I and 2-I. The phase behavior of these two systems were studied with differential scanning calorimetry. Computational studies such as the search for stable conformers, lattice-energy calculations, and Hirshfeld surface analysis were performed to shed light on the polymorphism, relative stability of the forms in each system, and contribution of intermolecular interactions to the overall stability of the systems. The study confirmed the effect of substituent size on the polymorphism of the compounds.
研究领域:
化学
·
材料科学
·
药物化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2017
·
IF 3.255
Wen-Peng Zhang,Dong-Ying Chen
The purpose of this work was to investigate the crystal structures and physicochemical properties of amisulpride polymorphs. Except of the previously reported polymorph (named as Form I), a new polymorphic form (named as Form II) was discovered through comprehensive solid-state screening experiments. Both polymorphic forms were characterized by single crystal X-ray structure analysis (SXRD), powder X-ray diffraction (PXRD), dynamic vapor sorption (DVS) and thermal analysis (TGA and DSC) as well. It has been found that the Forms I and II are of conformational polymorph with the main conformational difference around ethylsulfonyl group. Form II possesses lower hygroscopicity and better solubility compared with that of Form I, indicating Form II could be an alternate solid form for formulation development.
研究领域:
药学
·
材料科学
·
药物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 10
·期 4
·1119-1126
·
IF 7.779
Xin Zhao,Chensheng Lin,Shunda Yang,Haotian Tian,Chao Wang,Tao Yan,Jian Zhang,Bingxuan Li,Ning Ye,Min Luo
A non-centrosymmetric metal-free thiophosphate, γ-P4S3I2, was successfully synthesized utilizing polymorphism strategy in this study. γ-P4S3I2 crystallized in the space group of P43 and featured paralleled (P4S3I2)n molecular clusters. Importantly, it exhibited promising nonlinear optical (NLO) performances, such as a phase-matchable second harmonic generation (SHG) efficiency (0.5 × AgGaS2), wide band gap (2.38 eV), large birefringence (0.118@2050 nm), and wide infrared transparency, suggesting that γ-P4S3I2 may be a potential IR NLO candidate.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
Chemistry-An Asian Journal
·
2019
·Vol. 14
·期 6
·884-889
·
IF 3.698
Tingting Zhang,Zihao Zhao,Huili Ma,Yongming Zhang,Wang Zhang Yuan
Graphical Spatial relations : A pure organic luminogen (AN-MA) with isolated small conjugates and effective through-space conjugation was obtained through facile Diels–Alder cycloaddition. Owing to its flexible structure, two polymorphs were readily obtained. These exhibit bright visible emission and persistent room-temperature phosphorescence ( p -RTP) (see figure). Pure organic luminogens with persistent room-temperature phosphorescence ( p -RTP) have attracted increasing attention owing to their vital significance and potential applications in security inks, bioimaging, and photodynamic therapy. Previously reported p -RTP luminogens normally possessed through-bond conjugation. In this work, we report a pure organic luminogen, AN-MA, the Diels–Alder cycloaddition adduct of anthracene (AN) and maleic anhydride (MA), which possesses isolated phenyl groups and an anhydride moiety. AN-MA exhibits aggregation-enhanced emission (AEE) characteristics with efficiency of approximately 2 % and up to 8.5 % in solution and crystals, respectively. Two polymorphs of AN-MA were readily obtained that were able to generate UV emission from individual phenyl rings together with bright blue emission owing to the effective through-space conjugation. Moreover, p -RTP with a lifetime of up to approximately 1.6 s was obtained in the crystals. These results not only reveal a new system with both fluorescence and RTP dual emission but also suggest an alternative through-space conjugation strategy towards pure organic p -RTP luminogens with tunable emissions.
研究领域:
材料科学
·
有机化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF PHARMACEUTICS
·
2024
·
IF 5.3
Mengwei Wang,Olivia Aalling-Frederiksen,Anders Ø. Madsen,Kirsten M.Ø. Jensen,Mads R.V. Jørgensen,Junbo Gong,Thomas Rades,Inês C.B. Martins
The influence of different preparation methods on the physicochemical properties of amorphous solid forms have gained considerable attention, especially with recent publications on pharmaceutical poly a morphism. In the present study, we have investigated the possible occurrence of poly a morphism in the drug celecoxib (CEL) by investigating the thermal behavior, morphology, structure, molecular mobility and physical stability of amorphous CEL obtained by quench-cooling (QC), ball milling (BM) and spray drying (SD). Similar glass transition temperatures but different recrystallization behaviors were observed for CEL-QC, CEL-BM and CEL-SD using modulated differential scanning calorimetry analysis. A correlation between the different recrystallization behaviors of the three CEL amorphous forms and the respective distinct powder morphologies, was also found. Molecular dynamics simulations however, reveal that CEL presents similar molecular conformational distributions when subjected to QC and SD. Moreover, the obtained molecular conformational distributions of CEL are different from the ones found in its crystal structure and also from the ones found in the lowest-energy structure obtained by quantum mechanical calculations. The type and strength of CEL hydrogen bond interactions found in CEL-QC and CEL-SD systems are almost identical, though different from the ones presented in the crystal structure. Pair distribution function analyses and isothermal microcalorimetry show similar local structures and structural relaxation times, respectively, for CEL-QC, CEL-BM and CEL-SD. The present work shows that not only similar physicochemical properties (glass transition temperature, and structural relaxation time), but also similar molecular conformational distributions were observed for all prepared CEL amorphous systems. Hence, despite their different recrystallization behaviors, the three amorphous forms of CEL did not show any signs of poly a morphism.
研究领域:
药剂学
·
材料科学
✓ 已验证
DOI
PubMed
高影响因子
CRYSTAL GROWTH & DESIGN
·
2018
·
IF 3.972
Meng Liu,Guowen Shen,Zhong Yuan,Sean Parkin,Faquan Yu,Mingtao Zhang,Sihui Long,Tonglei Li
To gain understanding of how the variation in local weak interactions influences intermolecular interactions and subsequent crystal packing, four analogues of 2-(3-chloro-2-methyl-phenylamino)-nicotinic acid [clonixin] were synthesized by replacing the chlorine with fluorine (1), bromine (2), iodine (3), and hydrogen (4). Compounds 1, 2, and 3 were found to be polymorphic as shown by the discovery of two forms for each (1-I, 1-II; 2-I, 2-II; and 3-I, 3-II, respectively), while compound 4 has only a single identified form. Similar to clonixin, the analogue molecules in their crystals are associated either by the acid–acid dimer homosynthon or the acid–pyridine heterosynthon, depending on the dihedral angle between the two aromatic rings. Moreover, forms 2-I, 2-II, 3-I, and 3-II are isostructural to clonixin forms I and IV, compound 4 is isostructural to compound 1 form I, and 2-II is structurally similar to clonixin form II. The phase behaviors of these polymorphic systems were studied by differential scanning calorimetry, and it was found that 2-II converted into 2-I when heated, 3-II transformed into 3-I upon heating, and 1-II underwent transition into 1-I. Quantum mechanical calculations including conformational energy, hydrogen-bonding strength, lattice energy, and molecular contact were performed to provide further insight into the polymorphism. Given that all halogen derivatives are polymorphic, while the hydrogen analogue (4) is not, our study highlights the importance of intermolecular interactions in determining crystal packing.
研究领域:
药物化学
·
晶体学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2015
·Vol. 98
·期 8
·2451-2458
·
IF 2.61
Meilu Gong,Fengqi Lu,Xiaojun Kuang,Xiaodi Yu,Quanchao Wang,Xiaohui Li,Liang Fang
Molten salt synthesis (MSS) of the eight-layer hexagonal perovskite Ba 8 NiTa 6 O 24 was performed using mixed KCl–NaCl salts in comparison with solid-state synthesis (SSS). In the SSS, the hexagonal Ba 8 NiTa 6 O 24 formed at 1300°C via a reaction between cubic Ba 3 NiTa 2 O 9 and hexagonal Ba 5 Ta 4 O 15 . While the MSS did not lower the synthesis temperature of the hexagonal Ba 8 NiTa 6 O 24 but stabilized an unusual A- and B-site-deficient cubic perovskite polymorph of Ba 8 NiTa 6 O 24 below 1350°C as an intermediate phase prior to transforming into the hexagonal phase. This cubic polymorph contains ~3% A-site and ~9.5% B-site vacancies plus ~3% Ba cations in the B sites and demonstrated remarkable stability below 1350°C when without presence of the molten salt. The cubic polymorph displayed larger ε ~ 36 and τ f ~ 110 ppm/°C than the hexagonal polymorph from the MSS (ε ~ 29 and τ f ~ 67 ppm/°C). The hexagonal SSS-processed ceramics showed advantageous dielectric properties ( Q f ~ 52 000 GHz, τ f ~ 30 ppm/°C) over both cubic and hexagonal MSS-processed ones ( Q f ~ 18 600–20 000 GHz), while displaying anisotropic grain growth. The anisotropic grain growth was suppressed significantly by the MSS processing.
研究领域:
材料科学
·
陶瓷学
·
固态化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）