The new R739×5 data set from the Non-Covalent Interactions Atlas series (www.nciatlas.org) focuses on repulsive contacts in molecular complexes, covering organic molecules, sulfur, phosphorus, halogens, and noble gases. Information on the repulsive parts of the potential energy surface is crucial for the development of robust empirically parametrized computational methods. We use the new data set of highly accurate CCSD(T)/CBS interaction energies to test selected density functional theory (DFT) and semiempirical quantum-mechanical methods. The double-hybrid functionals were the best performing, with the revDSD-PBEP86-D3 being the most accurate DFT method, followed by the range-separated ωB97X functionals. Out of semiempirical methods, GFN2-xTB yielded the best results. On the example of the PM6 method, we analyze the source of error and its relation to the difficulties in the description of conformational energies, and we also devise an immediately applicable correction that fixes the most serious uncorrected issues previously encountered in practical calculations.
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http://dx.doi.org/10.1021/acs.jctc.0c01341 | DOI Listing |
Angew Chem Int Ed Engl
January 2025
Indian Institute of Chemical Technology, Organic Synthesis and Process Chemistry, Uppal Road, 500607, Hyderabad, INDIA.
Catalytic hydrocupration of unsaturated carbon-carbon bonds to generate organometallic nucleophiles has recently become an attractive alternative to conventional stoichiometric reagents in the stereoselective synthesis. Herein, we have developed an efficient and economical method to synthesize enantiopure α-hydroxy allyl ketones via a copper hydride (CuH)-catalyzed hydroacylation of alkoxyallenes, a significant advancement given the scarcity of reports on such scaffolds in the literature. DFT calculations reveal that this reaction proceeds through the nucleophilic attack of a kinetically favourable Z-selective allyl-copper intermediate on acid anhydrides via a six-membered chair-like transition state, stabilized by strongly attractive non-covalent interactions that ultimately leads to high level of enantioselectivities using the simple BINAP ligand.
View Article and Find Full Text PDFAdv Sci (Weinh)
January 2025
Ministry of Education Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Department of Chemistry, Tsinghua University, Beijing, 100084, P. R. China.
The massive amount of indoleamine 2,3-dioxygenase 1 (IDO-1) in tumor cells and tumor-associated immune cells forms a feedback loop that maintains immunosuppressive tumor microenvironment (ITM) and causes immune escape, resulting in the poor prognosis of platinum chemotherapeutics. However, the effective systemic administration of platinum drugs and IDO-1 inhibitors is strictly limited by their distinct chemical construction, different pharmacokinetic profiles, and heterogeneous distributions. Herein, a novel supramolecular method with the capability to modulate tumor microenvironment is proposed aiming at potentiating the antitumor efficacy of chemoimmunotherapy.
View Article and Find Full Text PDFJACS Au
January 2025
Instituto de Química, Universidade Federal do Rio Grande do Sul-UFRGS, Av. Bento Gonçalves 9500, 91501-970 Porto Alegre, Rio Grande do Sul, Brazil.
Understanding the mechanism of drug action in biological systems is facilitated by the interactions between small molecules and target chiral biomolecules. In this context, focusing on the enantiomeric recognition of carbohydrates in solution through steady-state fluorescence emission spectroscopy is noteworthy. To this end, we have developed a third generation of chiral optical sensors for carbohydrates, distinct from all of those previously presented, which interact with carbohydrates to form non-covalent probe-analyte interactions.
View Article and Find Full Text PDFInt J Pharm
January 2025
Pharmaceutical Nanotechnology Research Laboratory, Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research Hyderabad Telangana India. Electronic address:
Supramolecular polymers represent a distinctive class of polymers exhibiting similarities with covalent polymers, while also showcasing distinctive attributes such as responsiveness, reversibility, self-healing, and dynamism, which are conferred upon them by non-covalent interactions including hydrogen bonding, electrostatic interactions, van der Waals forces, π-π arrangements, and donor-acceptor interactions, among others. The noteworthy features of these supramolecular polymers have attracted considerable interest across diverse fields of science and technology, spanning electrochemistry, environmental science, drug delivery and tissue engineering. Nonetheless, the prevailing research focus in the realm of supramolecular polymers revolves around the advancement of novel methodologies aimed at synthesizing a broad spectrum of polymers characterized by diverse topologies.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
January 2025
Department of Chemistry, COMSATS University Islamabad, Abbottabad Campus, University Road, Abbottabad 22060 Pakistan.
A highly selective naphthalimide based fluorescent probe PBQ was designed for investigation of doxycycline (DOX) in various real samples. The synthesized probe PBQ showed maximum emission intensity at 395 nm and exhibited selective quenching response-based on photoinduced electron transfer (PET) mechanism even in the presence of various competing and interfering drugs, amino acids, cations and anions. Furthermore, probe PBQ showed excellent AIEE properties with red shift in maximum emission wavelength due to formations of J-aggregates.
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