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This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry", copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.1c02467. Platinum-based anticancer drugs are actively developed utilizing lipophilic ligands or drug carriers for the efficient penetration of biomembranes, reduction of side effects, and tumor targeting. We report the development of a supramolecular host–guest system built on cationic platinum(II) compounds bearing ligands anchored in the cavity of the macrocyclic host. The host–guest binding and hydrolysis process on the platinum core were investigated in detail by using NMR, MS, X-ray diffraction, and relativistic DFT calculations. The encapsulation process in cucurbit[7]uril unequivocally promotes the stability of hydrolyzed dicationic cis-[PtII(NH3)2(H2O)(NH2-R)]2+ compared to its trans isomer. Biological screening on the ovarian cancer lines A2780 and A2780/CP shows time-dependent toxicity. Notably, the reported complex and its β-cyclodextrin (β-CD) assembly achieve the same cellular uptake as cisplatin and cisplatin@β-CD, respectively, while maintaining a significantly lower toxicity profile.

The applications of NMR chemical shift calculations have shown an extraordinary expansion and diversification in the last decade. A significant proportion of these efforts have been devoted to interpreting and reproducing NMR experiments within different solvent environments and in a variety of complexes containing heavy element(s) or molecules of an open-shell nature. Thus, it is the purpose of this chapter to present a broad overview of the state-of-the-art in the field of computational NMR spectroscopy with a particular focus on applications for the prediction of NMR spectra, including NMR chemical shifts of diamagnetic and paramagnetic systems. At the same time, this chapter provides an analysis of the quantitative methodologies developed during recent years, including representative applications to illustrate the historical evolution of this field. Important aspects of the dynamical or solvent effects, and relativistic contributions are also mentioned, highlighting the advantages and limitations of the available methodologies.

1H NMR spectroscopy has become an important technique for the characterization of transition-metal hydride complexes, whose metal-bound hydrides are often difficult to locate by X-ray diffraction. In this regard, the accurate prediction of 1H NMR chemical shifts provides a useful, but challenging, strategy to help in the interpretation of the experimental spectra. In this work, we establish a density-functional-theory protocol that includes relativistic, solvent, and dynamic effects at a high level of theory, allowing us to report an accurate and reliable interpretation of 1H NMR hydride chemical shifts of iridium polyhydride complexes. In particular, we have studied in detail the hydride chemical shifts of the [Ir6(IMe)8(CO)2H14]2+ complex in order to validate previous assignments. The computed 1H NMR chemical shifts are strongly dependent on the relativistic treatment, the choice of the DFT exchange–correlation functional, and the conformational dynamics. By combining a fully relativistic four-component electronic-structure treatment with ab initio molecular dynamics, we were able to reliably model both the terminal and bridging hydride chemical shifts and to show that two NMR hydride signals were inversely assigned in the experiment., A new strategy by computational 1H NMR spectroscopy was used to predict and support the characterization of complex metal polyhydrides. A density-functional-theory protocol including relativistic, solvent, and dynamic effects at a high level of theory was established for the [Ir6(IMe)8(CO)2H14]2+ complex. The combination of a relativistic four-component electronic-structure treatment with ab initio molecular dynamics provided a means to accurately model both terminal and bridging hydride shifts, showing that two signals were inversely assigned in the NMR experiment.

Introduction Laerdal Learning Application (LLEAP)-compatible simulation manikins lack some specific functions that can be useful in anesthesia simulation scenarios. Our objective was to develop a software-based anesthesia workstation with a pharmacokinetic model for inhaled anesthetics for this simulation platform. Methods A Windows Presentation Foundation application that emulates an Aespire anesthesia workstation was created. The Gas Man simulator (Med Man Simulations) was used as a reference for the pharmacokinetic model. A concordance analysis was made between the results obtained by our model and the reference, in open and semiclosed circuit, in both 70- and 140-kg patients. Results The mean of the differences between the compartments was less than 0.01 vol% in all circumstances. The percentile rank P2.5 to P97.5 was less than 0.5 vol% in all compartments, except for the open circuit compartment. Conclusions No significant differences were found between both pharmacokinetic models. We consider that our software-based anesthesia workstation can be useful for simulating mechanical ventilation and halogenated administration in different scenarios.

The incarceration of o‐benzyne and 27 other guest molecules within hemicarcerand 1, as reported experimentally by Warmuth, and Cram and co‐workers, respectively, has been studied by density functional theory (DFT). 1H‐NMR chemical shifts, rotational mobility and conformational preference of the guests within the supramolecular cage were determined, which showed intriguing correlations of the chemical shifts with structural parameters of the host‐guest system. Furthermore, based on the computed chemical shifts reassignments of some NMR signals are proposed. This affects in particular the putative characterization of the volatile benzyne molecule inside a hemicarcerand, for which our CCSD(T) and KT2 results indicate that the experimentally observed signals are most likely not resulting from an isolated benzyne within the supramolecular host. Instead, we show that the guest reacted with an aromatic ring of the host, and this adduct is responsible for the experimentally observed signals The following organizations are thanked for financial support: MICINN (PhD-scholarship ACC CTQ2011-25086/BQU, projects CTQ2014-59212-P, CTQ2015-70851-ERC, CTQ2017-87392-P), CONACyT project 2014-383560, GenCat (PhD scholarship ARR 2015_FI_B_00165, 2014SGR1202 and XRQTC network) and European Fund for Regional Development (FEDER, UNGI10-4E-801)

We report a combined experimental-theoretical study on the 31P NMR chemical shift for a number of trans-platinum(ii) complexes. Validity and reliability of the 31P NMR chemical shift calculations are examined by comparing with the experimental data. A successful computational protocol for the accurate prediction of the 31P NMR chemical shifts was established for trans-[PtCl2(dma)PPh3] (dma = dimethylamine) complexes. The reliability of the computed values is shown to be critically dependent on the level of relativistic effects (two-component vs. four component), choice of density functionals, dynamical averaging, and solvation effects. Snapshots obtained from ab initio molecular dynamics simulations were used to identify those solvent molecules which show the largest interactions with the platinum complex, through inspection by using the non-covalent interaction program. We observe satisfactory accuracy from the full four-component matrix Dirac-Kohn-Sham method (mDKS) based on the Dirac-Coulomb Hamiltonian, in conjunction with the KT2 density functional, and dynamical averaging with explicit solvent molecules.

The transfer hydrogenation of NHC-supported diborenes with dimethylamine borane proceeds with high selectivity for the trans-1,2-dihydrodiboranes(6). DFT calculations suggest a stepwise proton-first-hydride-second reaction mechanism via an intermediate μ-hydrodiboronium dimethylaminoborate ion pair.

We report a combined experimental-theoretical study on the 31P NMR chemical shift for a number of trans-platinum(ii) complexes. Validity and reliability of the 31P NMR chemical shift calculations are examined by comparing with the experimental data. A successful computational protocol for the accurate prediction of the 31P NMR chemical shifts was established for trans-[PtCl2(dma)PPh3] (dma = dimethylamine) complexes. The reliability of the computed values is shown to be critically dependent on the level of relativistic effects (two-component vs. four component), choice of density functionals, dynamical averaging, and solvation effects. Snapshots obtained from ab initio molecular dynamics simulations were used to identify those solvent molecules which show the largest interactions with the platinum complex, through inspection by using the non-covalent interaction program. We observe satisfactory accuracy from the full four-component matrix Dirac-Kohn-Sham method (mDKS) based on the Dirac-Coulomb Hamiltonian, in conjunction with the KT2 density functional, and dynamical averaging with explicit solvent molecules.