Article
Chemistry, Organic
Guilherme L. Kosteczka, Rafael N. Soek, Wagner E. Richter, Renan B. Campos
Summary: This study explores the competitive formation of isomeric bridged lactams via acid-catalyzed intramolecular Schmidt reactions from 3-azidoethylcyclopentanones using density functional theory (DFT) calculations. The results indicate that specific substituents at alpha-carbons can efficiently control the reaction's regioselectivity through lone pair-cation interactions or steric hindrance, while cation-pi interactions are less effective.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Yunxiang Lei, Junfang Yang, Wenbo Dai, Yisha Lan, Jianhui Yang, Xiaoyan Zheng, Jianbing Shi, Bin Tong, Zhengxu Cai, Yuping Dong
Summary: This study developed a series of organic host-guest doped materials exhibiting strong thermally activated delayed fluorescence and efficient room temperature phosphorescence. Molecular dynamics simulations were utilized to investigate the molecular packing of guest molecules in the host matrix.
Article
Chemistry, Multidisciplinary
Takumi Kariya, Hayato Hasegawa, Taro Udagawa, Yusaku Inada, Kyoko Nishiyama, Mieko Tsuji, Tasuku Hirayama, Tatsuo Suzutani, Naoki Kato, Shingo Nagano, Hideko Nagasawa
Summary: This study investigates the role of the absolute configuration of the C-6 carbon of the substrate polyene in the stereocontrol of the intramolecular Diels-Alder reaction (IMDA). The results show that Fsa2 exhibits consistent stereoselectivity, while Phm7 shows different stereoselectivity depending on the configuration of the 6-methyl group. The study also discovers a unique relationship between the stereochemistry of decalins and their antibacterial activity.
Article
Chemistry, Physical
Bo Li, Tiejun Xiao, Hujun Shen, Mingsen Deng, Feng Long Gu
Summary: An unprecedented intramolecular-locked strategy is proposed to design NLO materials with remarkable static first hyperpolarizability. This strategy involves the import of a large steric hindrance group to decrease torsion angles and enhance intramolecular charge transfer, resulting in improved performance of NLO materials.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Hao Chen, Nan An, Yanqing Wang, Somnath Mukherjee, Jiani Ma, Jing Liu, Yu Fang, Gang Wang, Hongtao Bian
Summary: Three new boron dipyrromethene derivatives with electron donor substituents at 2,6-positions were synthesized and exhibited intramolecular charge transfer (ICT) character. Broadband femtosecond transient absorption spectroscopy was used to detect the CT and CS states in different solvents. Electrolysis experiments provided a solid foundation for the assignment of the fs-TA results. In addition, density functional theory calculations confirmed the ICT character of the compounds. Decorating the BODIPY core with electron-donating substituents is important for adjusting its photofunctional behaviors, and the solvent polarity can easily regulate the photophysical processes.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Organic
Xiaolin Yue, Qingyang Zhou, K. N. Houk
Summary: In this study, the thermal rearrangement of basketene to Nenitzescu's hydrocarbon was investigated using quantum mechanics. Both the sequential retro-Diels-Alder followed by Cope rearrangement and the thermally forbidden retro-[2 + 2] cycloaddition were studied, and the controlling role of orbital symmetry was demonstrated.
JOURNAL OF ORGANIC CHEMISTRY
(2023)
Article
Chemistry, Organic
Abdul Shiraj, Raghunath O. Ramabhadran, Krishna N. Ganesh
Summary: Replacing alpha(CH2) with NH in monomers of standard aeg PNA and its homologue beta-ala PNA leads to aza-PNA monomers, which can form either an 8-membered H-bonded ring or a 5-membered N alpha H-alpha CO bond to stabilize E-type rotamers. These aza-PNA oligomers with exclusive E rotamers and intraresidue backbone H-bonding can modulate their DNA/RNA binding and assembling properties.
Article
Chemistry, Physical
Zhen Tang, Boxiao Shao, Wei Wu, Peifeng Su
Summary: In this study, a new energy decomposition analysis method called GKS-EDA(TD) is proposed to investigate intermolecular interactions in systems where one monomer is in a singly excited state and others are in their ground states. Based on computational results, GKS-EDA(TD) divides the total interaction energy with excited states into several components. The method is applied to explore intermolecular interactions and excitation energy contribution in C60 nucleic acid base complexes.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Microbiology
Zhihua Wang, Qiuke Li, Jinze Li, Jiawei Li, Lu Shang, Shuli Chou, Yinfeng Lyu, Anshan Shan
Summary: Antibiotic resistance is a serious issue, and antimicrobial peptides are considered promising alternatives to antibiotics due to their unique killing mechanism. This study designed a series of Trp-rich peptides and found that VW5 exhibited significant antimicrobial effects without causing toxicity to the skin through in vivo experiments.
FRONTIERS IN MICROBIOLOGY
(2021)
Article
Chemistry, Multidisciplinary
Aymard Didier Tamafo Fouegue, Vincent de Paul Zoua, Gervais Ndongo Kounou, Brice Laure Ndjopme Wandji, Julius Numbonui Ghogomu, Rahman Abdoul Ntieche
Summary: This paper investigates the adsorption ability of both pure and boron-doped C-24 towards the anticancer drug temozolomide using the DFT/M05-2X-D3/6-31+G(d,p) theoretical chemistry method. The results show that boron-doped C-24 forms a stable molecular complex with temozolomide, demonstrating its good adsorption ability.
NANOSCALE ADVANCES
(2023)
Article
Chemistry, Physical
Tsukasa Tada
Summary: This article reports on quantum chemical studies of possible molecular devices based on electric field-induced intramolecular charge transfer (EFIMCT). By applying an external electric field to molecular systems along the charge transport direction, intramolecular charge transfer can be induced, providing a potential switching mechanism independent of the electron-phonon coupling effect. The study suggests that the development of switching devices working at low bias voltage is feasible if the molecular system is properly designed.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Physical
Tsukasa Tada
Summary: This study focuses on quantum chemical investigations of molecular devices based on electric field-induced intramolecular charge transfer (EFIMCT). The results suggest that practical switching devices working at low bias voltage are feasible if the molecular system is properly designed. The potential for molecular memory devices based on EFIMCT is also discussed. However, there are still challenges to be addressed in developing practical molecular devices.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Chemistry, Organic
Teddy Herriman, Robert K. Szilagyi
Summary: This study reveals the mechanism of peptide bond formation catalyzed by collagenase by evaluating different chemical models and levels of theory. The experimental results show that the barrier height for the rate determining step of this reaction is 106 kJ mol(-1), which has fundamental implications for understanding enzyme catalyzed peptide bond formation, peptide/protein stability, and the origin of life.
ORGANIC & BIOMOLECULAR CHEMISTRY
(2023)
Article
Chemistry, Organic
Wei Cai, Yanlin He, Yiming Zhou, You Huang
Summary: The unprecedented catalyst-controlled divergent cyclizations of Morita-Baylis-Hillman carbonates have been established, leading to efficient synthesis of 1,2-dihydroquinolines and 4H-3,1-benzoxazines. DFT calculations have provided a deeper understanding of these reaction modes and chemoselectivity.
JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Physical
Sabyasachi Chakraborty, Kalyaneswar Mandal, Raghunathan Ramakrishnan
Summary: Intramolecular ion-pair interactions play a crucial role in shaping the structure and function of molecules. A thermodynamic cycle based on isoelectronic and alchemical mutation is proposed to estimate the intramolecular ion-pair interaction energy. The energies of 26 benchmark molecules with common ion-pair combinations are determined and compared with results obtained using intramolecular symmetry-adapted perturbation theory.
JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Chemistry, Multidisciplinary
Zi Li, Yong Yang, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Martin J. Paterson, Yasuteru Shigeta, Steven R. Kirk, Samantha Jenkins
Summary: This study investigated the impact of a static electric field and unchirped and chirped laser pulses on cycl[3.3.3]azine molecules using NG-QTAIM, revealing that the variations in energy gap between the lowest lying singlet and triplet excited states were significantly greater for laser pulses than for static E-field. The response to laser pulses induced a continuous range of chemical character, indicating its unique ability to induce polarization effects in the form of mixed bond types. Furthermore, the chirped laser pulse was found to lead to more frequent instances of inverting the singlet-triplet gap compared to the unchirped pulse, demonstrating its potential for designing more efficient organic light-emitting diode devices.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Stuart Burnett, Connor Bourne, Alexandra M. Z. Slawin, Tanja van Mourik, Andreas Stasch
Summary: The study presents a new magnesium complex containing a stable dianion of an aliphatic ketone. The complex undergoes reduction reactions or CH activation reactions when reacted with aliphatic ketones.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2022)
Article
Chemistry, Physical
Zi Li, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Steven R. Kirk, Samantha Jenkins
Summary: This paper introduces a new development in the investigation of the chirality of ethane using the next generation quantum theory of atoms in molecules (NG-QTAIM). A new isomer type Q(sigma) is discovered and defined as a 'null-isomer'. The study suggests that the staggered geometry of ethane can be explained by steric effects rather than hyper-conjugation. It also finds that the application of an electric field can reduce the steric effects.
CHEMICAL PHYSICS LETTERS
(2022)
Article
Chemistry, Physical
Herbert Fruechtl, Lorna M. Robertson, Tanja van Mourik
Summary: DFT calculations suggest that combining an electric field with electronic excitation is a promising method to control the configuration of a molecular switch based on amino-imino tautomerisation. By studying the effect of an electric field in the direction of a moving hydrogen atom on the energy barrier, the researchers show that experimentally accessible ranges of electric fields and photons are sufficient to induce the desired switch configuration. Excitation to states with inverted geometry results in reversible switching without reversing the electric field.
Article
Chemistry, Inorganic & Nuclear
Stuart Burnett, Matthew de Vere-Tucker, Matthew Davitt, David B. Cordes, Alexandra M. Z. Slawin, Rochelle Ferns, Tanja van Mourik, Andreas Stasch
Summary: This study reports the oxidative addition reactions of Dimagnesium(I) complexes with iodoarenes. The structurally characterized complexes include those with pyrazol-4-ylidene and imidazol-2-ylidene ligands.
ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE
(2022)
Article
Chemistry, Physical
Zi Li, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Steven R. Kirk, Samantha Jenkins
Summary: Using the newly introduced spanning stress tensor trajectory U-sigma-space construction, a chirality investigation of singly and doubly substituted ethane with halogen substituents was conducted. It was found that the singly substituted ethane was overall achiral, while the achiral character of the doubly substituted ethane was mainly influenced by the presence of the very light F atom.
CHEMICAL PHYSICS LETTERS
(2022)
Editorial Material
Chemistry, Physical
Gabriel G. Balint-Kurti, Ria Broer, Peter H. M. Budzelaar, Hubertus J. J. van Dam, Fokke Dijkstra, Henk Eshuis, Gerrit C. Groenenboom, Martyn F. Guest, Remco W. A. Havenith, Anthony J. H. M. Meijer, Tanja van Mourik, Zahid Rashid
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Biochemistry & Molecular Biology
Yuting Peng, Wenjing Yu, Xinxin Feng, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Steven R. Kirk, Samantha Jenkins
Summary: In this study, we used next-generation QTAIM to explain the cis-effect for two families of molecules by tracking the motion of bond critical points in stress tensor trajectories. By associating bond-bending and bond-twisting components with cis- and trans-characteristics, qualitative agreement with existing experimental data was found, and predictions were made in the absence of experimental data.
Article
Multidisciplinary Sciences
Wenjing Yu, Zi Li, Yuting Peng, Xinxin Feng, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Steven R. Kirk, Samantha Jenkins
Summary: In this study, the chirality of alanine under a non-structurally distorting electric field was investigated using the stress tensor trajectory U-sigma space construction within the NG-QTAIM framework. The results showed that the sliding of the BCP and bond flexing significantly increased in the presence of the electric field, while the achiral character of alanine was observed.
Article
Chemistry, Physical
Xinxin Feng, Alireza Azizi, Tianlv Xu, Wenjing Yu, Xiaopeng Mi, Hui Lu, Herbert Fruchtl, Tanja van Mourik, Steven R. Kirk, Samantha Jenkins
Summary: In this investigation, the role of non-nuclear attractors (NNAs) of the neutral Li-2 dimer under the influence of parallel and perpendicular electric fields was studied. The next generation quantum theory of atoms in molecules (NG-QTAIM) interpretation was used to analyze the bonding using the stress tensor sigma(r) eigenvectors. Asymmetry induced by the electric fields was detected through the rotation of the stress tensor eigenvectors relative to the coordinate frame. The motion of the NNAs along the bond-path was found to correlate with bond metallicity, and the effect of electric field was compared with a stretching distortion. The unique ability of the stress tensor eigenvectors to detect rotation in high-symmetry systems was highlighted.
INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Hui Lu, Alireza Azizi, Xiao Peng Mi, Yu Wenjing, Yuting Peng, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Steven R. Kirk, Samantha Jenkins
Summary: In this study, the effect of a nonionizing ultrafast laser pulse on the electron dynamics of ethene molecule was simulated. The results showed that the shifts of C1-C2 bond critical points were up to 5.8 times higher after the pulse was switched off compared to a static electric field. NG-QTAIM was used to visualize and quantify directional chemical character, and it was found that some laser pulse frequencies increased polarization effects and bond strengths after the pulse was switched off. The study demonstrates the usefulness of NG-QTAIM in the field of ultrafast electron dynamics for the design and control of molecular electronic devices.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Biochemistry & Molecular Biology
Xiaotong Zhang, John Barrow, Tanja van Mourik, Michael Buhl
Summary: Using a combination of unconstrained and constrained molecular dynamics simulations, the binding affinities between two porphyrin derivatives (TMPyP4 and TEGPy) and the G-quadruplex (G4) of a DNA fragment modeling the insulin-linked polymorphic region (ILPR) were evaluated. The calculated and observed absolute free binding energy of TMPyP4 showed excellent agreement, thanks to the refined potential of mean force (PMF) approach. The study predicts a higher binding affinity of IPLR-G4 towards TEGPy, attributed to the stabilization provided by the polyether side chains of TMPyP4 through hydrogen bonding with the ether oxygen atoms.
Article
Chemistry, Inorganic & Nuclear
Stuart Burnett, Rochelle Ferns, David B. Cordes, Alexandra M. Z. Slawin, Tanja van Mourik, Andreas Stasch
Summary: This article reports on the different complexes obtained from the reactions of [(iPrDip)NacNac)Mg}(2)] with different reactants and reveals the structural characteristics of these complexes through experimental and computational studies.
INORGANIC CHEMISTRY
(2023)
Article
Chemistry, Multidisciplinary
Xiao Peng Mi, Hui Lu, Tianlv Xu, Herbert Fruchtl, Tanja van Mourik, Martin J. Paterson, Steven R. Kirk, Samantha Jenkins
Summary: A study using simulated circularly polarized laser pulses on ethane showed that the mechanical properties, particularly bond-flexing and bond-torsion, increase depending on the plane of polarization. These properties may increase or decrease after the laser pulses are switched off, depending on the polarization plane, due to directionally-dependent effects of excited states' long-lasting superpositions. The chiral properties of ethane were found to be formally achiral. The study briefly discusses future investigations using ultra-fast circularly polarized lasers.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2023)
Article
Chemistry, Physical
Tanja van Mourik, Herbert Fruchtl
Summary: Cyclic 5- and 7-ring structures with alternating single and double bonds and adjacent imino and amino groups are proposed as candidates for switches in molecular electronics, with amino-imino tautomerisation as the switching mechanism. These molecules exhibit a symmetric double-well potential, making them promising switch candidates for further investigation.
CHEMICAL PHYSICS IMPACT
(2021)
