A5026511996- DNA and Nucleic Acid Chemistry
- Advanced biosensing and bioanalysis techniques
- Synthesis and Properties of Aromatic Compounds
- Lung Cancer Research Studies
- Cancer therapeutics and mechanisms
- Neuroblastoma Research and Treatments
- Cytokine Signaling Pathways and Interactions
- Electrochemical Analysis and Applications
- Crystallography and molecular interactions
- Molecular Junctions and Nanostructures
- Synthesis and characterization of novel inorganic/organometallic compounds
- Advanced Chemical Physics Studies
- Porphyrin and Phthalocyanine Chemistry
- Psoriasis: Treatment and Pathogenesis
- Fullerene Chemistry and Applications
- Advanced Battery Materials and Technologies
- Coordination Chemistry and Organometallics
- Organic Electronics and Photovoltaics
- Photochromic and Fluorescence Chemistry
- Machine Learning in Materials Science
- Antibiotics Pharmacokinetics and Efficacy
- Arsenic contamination and mitigation
- Metal complexes synthesis and properties
- Chemical Analysis and Environmental Impact
- Viral-associated cancers and disorders
Alembic Pharmaceuticals (India)
2023
Italian Institute of Technology
2018-2020
Karlsruhe Institute of Technology
2017-2018
University of Münster
2015
Indian Institute of Science Education and Research Thiruvananthapuram
2010-2013
Indian Association for the Cultivation of Science
2013
Cochin University of Science and Technology
2011
We present the parametrization and benchmark of long-range corrected second-order density functional tight binding (DFTB), LC-DFTB2, for organic biological molecules. The LC-DFTB2 model not only improves fundamental orbital energy gaps but also ameliorates DFT self-interaction error overpolarization problem, further charge-transfer excited states significantly. Electronic parameters construction DFTB2 Hamiltonian as well repulsive potentials were optimized molecules containing C, H, N, O...
Structures of various conformers G-quartets (G4) with different types hydrogen bonding patterns have been investigated through levels Density Functional Theory (DFT). Their structure and stability has compared the diad (G2), triad (G3), pentad (G5) hexad (G6) guanine. The calculations show that G4 highest stabilization hydrogen-bond interaction which explains tendency guanine rich strands in telomeric region to favor formation quadruplex structure. We also performed for Li+, Na+, K+, Be2+,...
Stabilization of unstable mispairs on protonation in a DNA sequence can result change the conformation. Such sequences are being actively used for synthesis pH-driven molecular switches that have applications biological pH sensing. We studied various conformations different bases and their protonated forms using density functional theory (DFT) at B3LYP/6-31+G(d) M05-2X/6-31+G(d,p) levels. Both gas-phase aqueous-phase calculations reported. Solvent phase were done PCM COSMO solvation model....
The structure and electronic properties of guanine oligomers π stacks quartets (G-quartets) with circulene are investigated under an external field through first-principles calculations. An electric induces nonplanarity in the aggregates also leads to increase H-bond distances. calculations reveal that binding energy circulenes G-quartets increases on application along stacking direction. HOMO-LUMO gap decreases substantially influence field. contribution a simple dipole-dipole interaction...
While the Watson-Crick base pairs are known to stabilize DNA double helix and play a vital role in storage/replication of genetic information, their replacement with non-Watson-Crick has recently been shown have interesting practical applications. Nowadays, theoretical calculations routinely performed on very complex systems gain better understanding how molecules interact each other. We not only bring together some basic concepts mispaired or unnatural nucleobases other but also look at...
The electrocatalysis of [5,10,15,20-tetrakis(4-methoxyphenyl)porphyrinato]Mn(III)chloride (TMOPPMn(III)Cl) toward the oxidation trimethoprim was investigated by electrochemical and computational methods. Voltammetric analysis demonstrates ability TMOPPMn(III)Cl to act as an electrocatalyst for trimethoprim. DFT calculations were performed at B3LYP level detect site well survey role manganese porphyrin in facile Quantum chemical affirm that deprotonation NH2 attached C4 is more energetically...
Abstract An artificial nucleoside surrogate with 1 H ‐imidazo[4,5‐ f ][1,10]phenanthroline ( P ) acting as an aglycone has been introduced into DNA oligonucleotide duplexes. This can act a bidentate ligand, and so is useful in the context of metal‐mediated base pairs. Several duplexes involving hetero pair imidazole have investigated. The stability incorporating respective Ag I ‐mediated pairs strongly depends on sequence context. Quantum mechanical/molecular mechanical (QM/MM) calculations...
Recently, inorganic double-helical structures based on simple lithium and phosphorus salts have been demonstrated. We analyzed the nature of bonding in these double helices LinPn (n = 7–9). Similar to DNA, noncovalent interactions cooperativity play an important role stabilizing helices. Cooperativity imparts additional stabilization 4.5 10.1 kcal/mol per Li–P pair. In addition, ionicity units further augments stability double-helix contrast with canonical base pairs where determine duplex...
A bacterial strain, GFAJ-1 was recently proposed to be substituting arsenic for phosphorus sustain its growth. We have performed theoretical calculations analyzing this controversial hypothesis by examining the addition of phosphate ribose and glucose. Dispersion corrected Density Functional Theory (DFT) in small molecules QM/MM on clusters derived from crystal structure are structures involved phosphorylation, considering both phosphates arsenates. The exothermicity as well activation...
Adaptive QM/MM (quantum mechanical/molecular mechanical) methods repartition molecules on‐the‐fly into the QM and MM regions based on a partitioning criterion. A density‐based scheme offers unique way of carrying out assignments presence/absence (non) covalent interactions between non‐QM core core. Here, we present two improvements to promote our adaptive strategy for calculations. First, bond formation/breaking processes are monitored using descriptor, define an region fly. Second, is made...
We previously reported a first set of hybrid topoisomerase II (topoII) poisons whose chemical core merges key pharmacophoric elements etoposide and merbarone, which are two well-known topoII blockers. Here, we report on the expansion this molecular scaffold present 16 more derivatives that have been designed, synthesized, characterized for their ability to block overall drug-like profile. Some these compounds act as poison exhibit good solubility, metabolic (microsomal) stability, promising...
The recently isolated heavy ketone (X2EO; E = Ge) shows interesting reactivity towards simple addition reactions that are unknown for the organic (EC) ketones. Density Functional Theory (DFT) calculations elucidate role of central atom and substituent effects on acetone, carbon dioxide water to formaldehyde, 2,4-dimethyl-3-pentanone, diphenyl their heavier (Si, analogs. NBO analysis reveals a large charge separation analogs, thereby increasing reactivity. activation barriers reduced by as...
The structures and proton-coupled behavior of adenine-thymine (A-T) a modified base pair containing thymine isostere, adenine-difluorotoluene (A-F), are studied in different solvents by dispersion-corrected density functional theory. stability the canonical Watson-Crick mismatched various with low high dielectric constants is analyzed. It demonstrated that A-F pairing favored constant. stabilization conformational changes induced protonation also analyzed for natural as well pair. DNA...
Human type II topoisomerases (TopoII) are essential for controlling DNA topology within the cell. For this reason, there a number of TopoII-targeted anticancer drugs that act by inducing cleavage mediated both TopoII isoforms (TopoIIα and TopoIIβ) in cells. However, recent studies suggest specific poisoning TopoIIα may be safer strategy treating cancer. This is because TopoIIβ appears to linked generation secondary leukemia patients. We recently reported enzyme-mediated complexes (in which...
MYC deregulation, a cardinal event in Burkitt lymphoma (BL) pathogenesis, necessitates the elucidation of molecular mechanisms governing activation to devise innovative and effective therapeutic strategies. The t(8;14)(q24;q32) chromosomal translocation commonly observed hematological malignancies results endowing cancer cells with competitive edge through heightened cell proliferation, cycle progression, apoptosis evasion, metabolic reprogramming. Recent discoveries recurrent mutations BL...
Photoluminescent Carbon Dots for Multicolor Patterning, Sensors, and
<b>Abstract ID 54869</b> <b>Poster Board 497</b> <b>Objectives:</b> Psoriasis is a chronic skin condition, affecting around 8 million patients in the Unites States of America. The role T helper type 1 (Th1) and 17 (Th17) mediated cytokine pathways psoriasis pathology has been validated clinically antibodies targeting these cytokines are highly effective moderate to severe psoriasis. However, antibody therapeutics come with high costs safety concerns. There huge unmet need for developing safe...
Abstract Psoriasis is a chronic skin condition, that affects ~8M patients in the United States. A majority (~7M) of suffer from mild to moderate form disease lacks safe & effective treatment options. Although antibodies targeting Th1/Th17 cytokines (eg IL12/IL23/IL17) are highly severe psoriasis, they not prescribed due high costs safety concerns. There huge unmet need for developing and non-steroidal topical therapies. Small molecule inhibitors pathways with optimal drug like properties...
DFT and NMR calculations performed on isophlorin (1) their derivatives (2–10) show that the 4O trans 2O, 2S (2 5) are anti-aromatic. The presence of strong S…S pπ-pπ bonding interactions stabilizes planar structure (5) compared to non-planar cis-isomer (8). Isoph lorins predicted have very low electron reorganization energies (λelectron∼0.10eV) which remain unaffected by puckering through steric or solvation in aqueous media. We predict isophlorins be ideal candidates for n-Channel organic...