Publications de Bruno Simões de Almeida

Atomic-level structure of the amorphous drug atuliflapon via NMR crystallography

Manuel Cordova, David Lyndon Emsley, Albert Hofstetter, Federico Maria Paruzzo, Martins Balodis, Pierrick Berruyer, Bruno Simões de Almeida, Daria Torodii

We determine the complete atomic-level structure of the amorphous form of the drug atuliflapon, a 5-lipooxygenase activating protein (FLAP) inhibitor, via chemical-shift-driven NMR crystallography. The ensemble of preferred structures allows us to identify ...

2024

Barriers to resolution in 1H NMR of rotating solids

David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

The role of 1H solid-state NMR in structure elucidation of solids is becoming more preponderant, particularly as faster magic-angle spinning rates (MAS) become available which improve 1H detected assignment strategies. However, current 1H spectral resoluti ...

Academic Press Inc - Elsevier Science2023

Two-dimensional Pure Isotropic Proton Solid State NMR

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

One key bottleneck of solid-state NMR spectroscopy is that H-1 NMR spectra of organic solids are often very broad due to the presence of a strong network of dipolar couplings. We have recently suggested a new approach to tackle this problem. More specifica ...

Wiley-VCH Verlag GmbH2023

Improvements in Resolution of 1H NMR of Solids

David Lyndon Emsley, Bruno Simões de Almeida

Magic angle spinning (MAS) in 1H NMR has allowed progress from featureless spectra in static samples to linewidths of a few hundreds of Hertz for powdered solids at the fastest spinning rates available today (100-150 kHz). While this is a remarkable improv ...

SWISS CHEMICAL SOC2023

Development of strategies to improve 1H resolution in NMR of solids at 100 kHz magic-angle spinning

Bruno Simões de Almeida

In solid-state NMR, homonuclear dipolar couplings contribute greatly to the broadening of 1H spectral line shapes. Even at the fastest magic-angle spinning rates (MAS) available today [100-150kHz], the linewidths still extend over several hundred Hertz, li ...

EPFL2023

Pure Isotropic Proton NMR Spectra in Solids using Deep Learning

Manuel Cordova, David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

The resolution of proton solid-state NMR spectra is usually limited by broadening arising from dipolar interactions between spins. Magic-angle spinning alleviates this broadening by inducing coherent averaging. However, even the highest spinning rates expe ...

Wiley-VCH Verlag GmbH2023

Structure determination of an amorphous drug through large-scale NMR predictions

Manuel Cordova, David Lyndon Emsley, Albert Hofstetter, Federico Maria Paruzzo, Martins Balodis, Pierrick Berruyer, Bruno Simões de Almeida

Knowledge of the structure of amorphous solids can direct, for example, the optimization of pharmaceutical formulations, but atomic-level structure determination in amorphous molecular solids has so far not been possible. Solid-state nuclear magnetic reson ...

Nature Research2021

Pure Isotropic Proton Solid State NMR

David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida, Daria Torodii

Resolution in proton solid state magic angle sample spinning (MAS) NMR is limited by the intrinsically imperfect nature of coherent averaging induced by either MAS or multiple pulse sequence methods. Here, we suggest that instead of optimizing and perfecti ...

2021

Bayesian probabilistic assignment of chemical shifts in organic solids

Michele Ceriotti, Manuel Cordova, David Lyndon Emsley, Martins Balodis, Bruno Simões de Almeida

A prerequisite for NMR studies of organic materials is assigning each experimental chemical shift to a set of geometrically equivalent nuclei. Obtaining the assignment experimentally can be challenging and typically requires time-consuming multidimensional ...

2021

Theory and simulations of homonuclear three-spin systems in rotating solids

David Lyndon Emsley, Gabriele Stevanato, Pinelopi Moutzouri, Bruno Simões de Almeida

The homonuclear dipolar coupling is the internal spin interaction that contributes the most to the line shapes in magic-angle-spinning (MAS) H-1 NMR spectra of solids, and linewidths typically extend over several hundred Hertz, limiting the H-1 resolution. ...

2021

Fast remote correlation experiments for 1H homonuclear decoupling in solids

David Lyndon Emsley, Pinelopi Moutzouri, Bruno Simões de Almeida

In 1H MAS spectra, the residual homogeneous broadening under MAS is due to a combination of higher-order shifts and splittings. We have recently shown how the two-dimensional anti-z-COSY experiment can be used for the removal of the splittings. However, th ...

Academic Press Inc - Elsevier Science2020

Homonuclear Decoupling in H-1 NMR of Solids by Remote Correlation

David Lyndon Emsley, Federico Maria Paruzzo, Gabriele Stevanato, Pinelopi Moutzouri, Bruno Simões de Almeida

The typical linewidths of H-1 NMR spectra of powdered organic solids at 111 kHz magic-angle spinning (MAS) are of the order of a few hundred Hz. While this is remarkable in comparison to the tens of kHz observed in spectra of static samples, it is still th ...

Wiley-VCH Verlag GmbH2020