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Panwaria P, Das A. N···C═O n → π* Interaction: Gas-Phase Electronic and Vibrational Spectroscopy Combined with Quantum Chemistry Calculations. J Phys Chem A 2024; 128:4685-4693. [PMID: 38814588 DOI: 10.1021/acs.jpca.4c02181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2024]
Abstract
Herein, we have used gas-phase electronic and vibrational spectroscopic techniques for the first time to study the N···C═O n → π* interaction in ethyl 2-(2-(dimethylamino) phenyl) acetate (NMe2-Ph-EA). We have measured the electronic spectra of NMe2-Ph-EA in the mass channels of its two distinct fragments of m/z = 15 and 192 using a resonant two-photon ionization technique as there was extensive photofragmentation of NMe2-Ph-EA. Identical electronic spectra obtained in the mass channels of both fragments confirm the dissociation of NMe2-Ph-EA in the ionic state, and hence, the electronic spectrum of the fragment represents that of NMe2-Ph-EA only. UV-UV hole-burning spectroscopy proved the presence of a single conformer of NMe2-Ph-EA in the experiment. Detailed quantum chemistry calculations reveal the existence of a N···C═O n → π* interaction in all six low-energy conformers of NMe2-Ph-EA. A comparison of the IR spectrum of NMe2-Ph-EA acquired from the gas-phase experiment with those obtained from theoretical calculations indicates that the experimentally observed conformer has a N···C═O n → π* interaction. The present finding might be further valuable in drug design and their recognition based on the N···C═O n → π* interaction.
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Affiliation(s)
- Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
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2
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Wang XD, Zhu J, Wang DX. Intermolecular n→π* Interactions in Supramolecular Chemistry and Catalysis. Chempluschem 2023; 88:e202300288. [PMID: 37609956 DOI: 10.1002/cplu.202300288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 08/19/2023] [Accepted: 08/21/2023] [Indexed: 08/24/2023]
Abstract
The n→π* interactions describing attractive force between lone pairs (lps) of nucleophile and carbonyl or polarized unsaturated bonds have recently attracted growing attentions in various disciplines. So far, such non-covalent driving force are mainly concentrated to intramolecular systems. Intermolecular n→π* interactions in principle could produce fascinated supramolecular systems or facilitate organic reactions, however, they remain largely underexplored due to the very weak energy of individual interaction. This review attempts to give an overview of the challenging intermolecular n→π* interactions, much efforts emphasize the supramolecular systems, catalytic processes and spectroscopic measurements.
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Affiliation(s)
- Xu-Dong Wang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
| | - Jun Zhu
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
| | - De-Xian Wang
- Beijing National Laboratory for Molecular Sciences, CAS Key Laboratory of Molecular Recognition and Function, Institute of Chemistry, Chinese Academy of Sciences, Beijing, 100190, China
- University of Chinese Academy of Sciences, Beijing, 100049, China
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3
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Panwaria P, Das A. Modulation of n → π* Interaction in the Complexes of p-Substituted Pyridines with Aldehydes: A Theoretical Study. J Phys Chem A 2023. [PMID: 37463490 DOI: 10.1021/acs.jpca.3c03103] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
n → π* interaction is analogous to the hydrogen bond in terms of the delocalization of the electron density between the two orbitals. Studies on the intermolecular complexes stabilized by the n → π* interaction are scarce in the literature. Herein, we have studied intermolecular N···C═O n → π* interactions in the complexes of p-substituted pyridines (p-R-Py) with formaldehyde (HCHO), formyl chloride (HCOCl), and acetaldehyde (CH3CHO) using quantum chemistry calculations. We have shown that the strength of the n → π* interaction can be modulated by varying the electronic substituents at the donor and acceptor sites in the complexes. Variation of the substituents at the para position of the pyridine ring from the electron-withdrawing groups (EWGs) to the electron-donating groups (EDGs) results in a systematic increase in the strength of the n → π* interaction. The strength of this interaction is also modulated by tuning the electron density toward the carbonyl bond by substituting the hydrogen atom of HCHO with the methyl and chloro groups. The modulation of this interaction due to the electronic substitutions at the n → π* donor and acceptor sites in the complexes is monitored by probing the relevant geometrical parameters, binding energies, C═O frequency redshift, NBO energies, and electron density for this interaction derived from QTAIM and NCI index analyses. Energy decomposition analysis reveals that the electrostatic interaction dominates the binding energies of these complexes, while the charge transfer interaction, which is representative of the n → π* interaction, also has a significant contribution to these.
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Affiliation(s)
- Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune, Maharashtra 411008, India
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune, Maharashtra 411008, India
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Panwaria P, Das A. Effect of Substituents on the Intramolecular n→π* Interaction in 3-[2-(Dimethylamino) phenyl] propanal: A Computational Study. J Phys Chem A 2023; 127:3339-3346. [PMID: 37036493 DOI: 10.1021/acs.jpca.2c08641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2023]
Abstract
n→π* non-covalent interaction (NCI) and hydrogen bond have similarity in terms of delocalization of the electron density between the two orbitals involved in the interaction. Hydrogen bond (X-H···Y) involves delocalization of the lone pair electrons (n) on the Y atom into the σ* orbital of the X-H bond. In contrast, the n→π* interaction deals with delocalizing the lone pair electrons (n) on the N, O, or S atom into the π* orbital of a C═O group or aromatic ring. Herein, we have shown a resemblance of this weak n→π* interaction with the relatively stronger hydrogen bond in terms of folding the side chains in flexible molecules. This work reports the study of folding of the flexible side-chain in 3-[2-(dimethylamino) phenyl] propanal (DMAPhP) through a N···C═O n→π* interaction using various computational approaches such as NBO, QTAIM, and NCI analyses. The folding of the molecule by the n→π* interaction observed in this study is found to be similar to that present in the secondary structures of peptides or proteins through hydrogen bonding interactions. Interestingly, the stabilization of the global minimum conformer of DMAPhP by the n→π* interaction demonstrates the importance of this NCI in providing conformational preferences in molecular systems. Another important finding of this study is that the theoretical redshift obtained in the C═O stretching frequency of the most stable conformer of the DMAPhP is contributed mostly by the n→π* interaction as the C═O group is not involved in hyperconjugation with any neighboring heteroatom, which is a common phenomenon in any ester or amide. We have also demonstrated here that the strength of the intramolecular n→π* interaction can be modulated by varying the electronic substituents at the para position of the donor group involved in the interaction.
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Affiliation(s)
- Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
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Panwaria P, Juanes M, Mishra KK, Saragi R, Borish K, Usabiaga I, Camiruaga A, Fernández JA, Lesarri A, Das A. Microhydration of Phenyl Formate: Gas-Phase Laser Spectroscopy, Microwave Spectroscopy, and Quantum Chemistry Calculations. Chemphyschem 2022; 23:e202200330. [PMID: 35984348 DOI: 10.1002/cphc.202200330] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Revised: 08/17/2022] [Indexed: 01/04/2023]
Abstract
Herein, we have investigated the structure of phenyl formate⋅⋅⋅water (PhOF⋅⋅⋅H2 O) dimer and various non-covalent interactions present there using gas-phase laser spectroscopy and microwave spectroscopy combined with quantum chemistry calculations. Two conformers of PhOF⋅⋅⋅H2 O (C1 and T1), built on the two cis/trans conformers of the bare molecule, have been observed in the experiment. In cis-PhOF, there is an nCO → π A r * ${{{\rm \pi }}_{{\rm A}{\rm r}}^{{\rm {^\ast}}}}$ interaction between the lone-pair orbital of the carbonyl oxygen atom and the π* orbital of the phenyl ring, which persists in the monohydrated C1 conformer of PhOF⋅⋅⋅H2 O according to the NBO and NCI analyses. On the other hand, this interaction is absent in the trans-PhOF conformer as the C=O group is away from the phenyl ring. The C1 conformer is primarily stabilized by an interplay between O-H⋅⋅⋅O=C hydrogen bond and O-H⋅⋅⋅π interactions, while the stability of the T1 conformer is primarily governed by the O-H⋅⋅⋅O=C hydrogen bond. The most important finding of the present work is that the conformational preference of the PhOF monomer is retained in its monohydrated complex.
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Affiliation(s)
- Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Marcos Juanes
- Departamento de Química Física y Química Inorgánica, Facultad de Ciencias-I.U. CINQUIMA, Universidad de Valladolid, Paseo de Belén, 7, 47011, Valladolid, Spain
| | - Kamal K Mishra
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India.,Present address: Department of Chemistry, University of Kentucky, Lexington, Kentucky, 40503, USA
| | - Rizalina Saragi
- Departamento de Química Física y Química Inorgánica, Facultad de Ciencias-I.U. CINQUIMA, Universidad de Valladolid, Paseo de Belén, 7, 47011, Valladolid, Spain
| | - Kshetrimayum Borish
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
| | - Imanol Usabiaga
- Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, Leioa, 48940, Spain
| | - Ander Camiruaga
- Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, Leioa, 48940, Spain
| | - José A Fernández
- Department of Physical Chemistry, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Barrio Sarriena s/n, Leioa, 48940, Spain
| | - Alberto Lesarri
- Departamento de Química Física y Química Inorgánica, Facultad de Ciencias-I.U. CINQUIMA, Universidad de Valladolid, Paseo de Belén, 7, 47011, Valladolid, Spain
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research Pune, Dr. Homi Bhabha Road, Pashan, Pune, 411008, India
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Adamiak K, Sionkowska A. The influence of UV irradiation on fish skin collagen films in the presence of xanthohumol and propanediol. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2022; 282:121652. [PMID: 35907314 DOI: 10.1016/j.saa.2022.121652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 06/27/2022] [Accepted: 07/17/2022] [Indexed: 06/15/2023]
Abstract
Fish skin collagen films are widely used as adhesives in medicine and cosmetology. Ultraviolet (UV) irradiation can be considered as an effective sterilization method for biomaterials, however, it may also lead to material photodegradation. In this work, the influence of xanthohumol and propanediol on the physico-chemical properties of collagen films before and after UV irradiation was studied. Collagen for this research was extracted from silver carp skin and thin films were fabricated by the solution casting methods. The structure of films was researched using infrared spectroscopy. The surface properties of films were investigated using Atomic Force Microscopy (AFM) and contact angle measurements. Mechanical properties were measured as well. It was found that the addition of xanthohumol and propanediol modified the roughness of collagen films and their mechanical properties. UV irradiation led to the water loss from the film and modification of the collagen structure. In the presence of propanediol and xanthohumol the water loss after UV irradiation was smaller than in UV-irradiated collagen films without these additives.
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Affiliation(s)
- Katarzyna Adamiak
- Department of Biomaterials and Cosmetics Chemistry, Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarin 7 Street, 87-100 Torun, Poland; WellU sp.z.o.o, Wielkopolska 280, 81-531 Gdynia, Poland.
| | - Alina Sionkowska
- Department of Biomaterials and Cosmetics Chemistry, Faculty of Chemistry, Nicolaus Copernicus University in Torun, Gagarin 7 Street, 87-100 Torun, Poland
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Kumar S, Borish K, Dey S, Nagesh J, Das A. Sequence dependent folding motifs of the secondary structures of Gly-Pro and Pro-Gly containing oligopeptides. Phys Chem Chem Phys 2022; 24:18408-18418. [PMID: 35880873 DOI: 10.1039/d2cp01306a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Folding motifs of the secondary structures of peptides and proteins are primarily based on the hydrogen bonding interactions in the backbone as well as the sequence of the amino acid residues present. For instance, the β-turn structure directed by the Pro-Gly sequence is the key to the β-hairpin structure of peptides/proteins as well as a selective site for the enzymatic hydroxylation of pro-collagen. Herein, we have investigated the sequence dependent folding motifs of end-protected Gly-Pro and Pro-Gly dipeptides using a combination of gas phase laser spectroscopy, quantum chemistry calculations, solution phase IR and NMR spectroscopy and single crystal X-Ray diffraction (XRD). All three observed conformers of the Gly-Pro peptide in the gas phase have been found to have extended β-strand or polyproline-II (PP-II) structures with C5-C7 hydrogen bonding interactions, which correlates well with the structure obtained from solution phase spectroscopy and XRD. On the other hand, we have found that the Pro-Gly peptide has a C10/β-turn structure in the solution phase in contrast to the C7-C7 (i.e. 27-ribbon) structure observed in the gas phase. Although the lowest energy structure in the gas phase is not C10, we find that C7-C7 is an abundantly found structural motif of Pro-Gly containing peptides in the Cambridge Structural Database, indicating that the gas phase conformers are not sampling any unusual forms. We surmise that the role of the solvent could be crucial in dictating the preferential stabilization of the C10 structure in the solution phase. The present investigation provides a comprehensive picture of the folding motifs of the Gly-Pro and Pro-Gly peptides observed in the gas phase and condensed phase weaving a fine interplay of the intrinsic conformational properties, solvation, and crystal packing of the peptides.
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Affiliation(s)
- Satish Kumar
- Department of Chemistry, Indian Institute of Science Education and Research, Dr Homi Bhabha Road, Pashan, Pune-411008, India.
| | - Kshetrimayum Borish
- Department of Chemistry, Indian Institute of Science Education and Research, Dr Homi Bhabha Road, Pashan, Pune-411008, India.
| | - Sanjit Dey
- Department of Chemistry, Indian Institute of Science Education and Research, Dr Homi Bhabha Road, Pashan, Pune-411008, India.
| | - Jayashree Nagesh
- Solid State and Structural Chemistry Unit, Indian Institute of Science, Bangalore-560012, India.
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research, Dr Homi Bhabha Road, Pashan, Pune-411008, India.
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8
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Panwaria P, Das A. Understanding the n → π* non-covalent interaction using different experimental and theoretical approaches. Phys Chem Chem Phys 2022; 24:22371-22389. [PMID: 35822956 DOI: 10.1039/d2cp02070j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Herein, a perspective on the recent understanding of weak n → π* interaction obtained using different experimental and theoretical approaches is presented. This interaction is purely an orbital interaction that involves the delocalization of the lone pair electrons (n) on nitrogen, oxygen, and sulfur to the π* orbitals of CO, CN, and aromatic rings. The n → π* interaction has been found to profoundly influence the stabilization of peptides, proteins, drugs, and various small molecules. Although the functional properties of this non-covalent interaction are still quite underestimated, there are recent demonstrations of applying this interaction to the regulation of synthetic chemistry, catalysis, and molecular recognition. However, the identification and quantification of the n → π* interaction remain a demanding task as this interaction is quite weak and based on the electron delocalization between the two orbitals, while hyperconjugation interactions between neighboring atoms and the group involved in the n → π* interaction are simultaneously present. This review provides a comprehensive picture of understanding the n → π* interaction using different experimental approaches such as the X-ray diffraction technique, and electronic, NMR, microwave, and IR spectroscopy, in addition to quantum chemistry calculations. A detailed understanding of the n → π* interaction can help in modulating the strength of this interaction, which will be further helpful in designing efficient drugs, synthetic peptides, peptidomimetics, etc.
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Affiliation(s)
- Prakash Panwaria
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pashan, Pune-411008, India.
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research (IISER) Pune, Dr. Homi Bhabha Road, Pashan, Pune-411008, India.
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Sahariah B, Sarma BK. Spectroscopic evidence of n → π* interactions involving carbonyl groups. Phys Chem Chem Phys 2021; 22:26669-26681. [PMID: 33226050 DOI: 10.1039/d0cp03557b] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
n → π* has emerged as an important noncovalent interaction that can affect the conformations of both small- and macromolecules including peptides and proteins. Carbonyl-carbonyl (COCO) n → π* interactions involving CO groups are well studied. Recent studies have shown that the COCO n → π* interactions are the most abundant secondary interactions in proteins with a frequency of 33 interactions per 100 residues and, among the various secondary interactions, n → π* interactions are expected to provide the highest enthalpic contributions to the conformational stability of globular proteins. However, n → π* interactions are relatively weak and provide an average stabilization of about 0.25 kcal mol-1 per interaction in proteins. The strongest n → π* interaction could be as strong as a moderate hydrogen bond. Therefore, it is challenging to detect and quantify these weak interactions, especially in solution in the presence of perturbation from other intermolecular interactions. Accordingly, spectroscopic investigations that can provide direct evidence of n → π* interaction are limited, and the majority of papers published in this area have relied on X-ray crystallography and/or theoretical calculations to establish the presence of this interaction. The aim of this perspective is to discuss the studies where a spectroscopic signature in support of n → π* interaction was observed. As the "n → π* interaction" is a relatively new terminology, there remains the possibility of there being earlier studies where spectroscopic evidence for n → π* interactions was obtained but it was not discussed in light of the n → π* terminology. We noticed several such studies and, as can be expected, these studies were often overlooked in the discussion of n → π* interactions in the recent literature. In this perspective, we have also discussed these studies and provided computational support for the presence of n → π* interaction.
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Affiliation(s)
- Biswajit Sahariah
- New Chemistry Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Jakkur, Bangalore 560064, India.
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10
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Madhanagopal BR, Kumar J, Ganesh KN. Silver assisted stereo-directed assembly of branched peptide nucleic acids into four-point nanostars. NANOSCALE 2020; 12:21665-21673. [PMID: 33094774 DOI: 10.1039/d0nr05471b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Branched chiral peptide nucleic acids br(4S/R)-PNA with three arms of PNA-C4 strands were constructed on a central chiral core of 4(R/S)-aminoproline as the branching center. The addition of Ag+ triggered the self-assembly of branched PNAs through the formation of C-Ag+-C metallo base pairing of the three PNA C4 arms leading to non-covalent dendrimers, whose architecture is directed by the C4(R/S)-stereocenter of core 4-aminoproline. The 4S-aminoprolyl core enabled the precise formation of four-pointed nanostars that was not realised with 4R-aminoprolyl or acyclic, achiral aminoethyl glycyl PNA cores. The dendritic assembly of 4 pointed nanostars exhibited net chirality of base stacks in CD spectra, while the base stack assembly from br(4R)-PNA 2 was overall achiral. The results demonstrate that the silver assisted, 4S-aminoproline core stereo selective chiral assembly of branched PNAs manifests into nanostar morphology. The chiral branched PNAs open new vistas in the supramolecular organization of nucleic acids.
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Affiliation(s)
- Bharath Raj Madhanagopal
- Indian Institute of Science Education and Research (IISER) Tirupati, Karkambadi Road, Tirupati 517507, Andhra Pradesh, India.
| | - Jatish Kumar
- Indian Institute of Science Education and Research (IISER) Tirupati, Karkambadi Road, Tirupati 517507, Andhra Pradesh, India.
| | - Krishna N Ganesh
- Indian Institute of Science Education and Research (IISER) Tirupati, Karkambadi Road, Tirupati 517507, Andhra Pradesh, India. and Indian Institute of Science Education and Research (IISER) Pune, Dr Homi Bhabha Road, Pune 411008, Maharashtra, India
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Sarkar S, Ramanathan N, Sruthi P, Sundararajan K. Computational and experimental evidence of N–H…π and cooperative πN…π∗ interactions in pyrrole…benzene and pyrrole…ethylene heterodimers at low temperatures. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.127983] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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12
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Singh SK, Panwaria P, Mishra KK, Das A. Steric as well as n→π* Interaction Controls the Conformational Preferences of Phenyl Acetate: Gas‐phase Spectroscopy and Quantum Chemical Calculations. Chem Asian J 2019; 14:4705-4711. [DOI: 10.1002/asia.201901158] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Revised: 09/03/2019] [Indexed: 01/26/2023]
Affiliation(s)
- Santosh K. Singh
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
- Current Address: Department of ChemistryUniversity of Hawaii, Manoa Honolulu Hawaii 96822 USA
| | - Prakash Panwaria
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| | - Kamal K. Mishra
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
| | - Aloke Das
- Department of ChemistryIndian Institute of Science Education and Research (IISER) Pune Dr. Homi Bhabha Road Pashan, Pune- 411008 India
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13
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Kumar S, Mishra KK, Singh SK, Borish K, Dey S, Sarkar B, Das A. Observation of a weak intra-residue C5 hydrogen-bond in a dipeptide containing Gly-Pro sequence. J Chem Phys 2019; 151:104309. [DOI: 10.1063/1.5115040] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Affiliation(s)
- Satish Kumar
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Kamal K. Mishra
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Santosh K. Singh
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Kshetrimayum Borish
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Sanjit Dey
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
| | - Biplab Sarkar
- Department of Chemistry, North Eastern Hill University, Shillong, Meghalaya 793022, India
| | - Aloke Das
- Department of Chemistry, Indian Institute of Science Education and Research, Dr. Homi Bhabha Road, Pashan, Pune 411008, India
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