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   https://doi.org/10.1039/c9cc01402k  

   Pace, Vittorio; Holzer, Wolfgang; Ielo, Laura; Shi, Shicheng; Meng, Guangrong; Hanna, Mina; Szostak, Roman; Szostak, Michal (April 2019, Chemical Communications)

   The structure and spectroscopic properties of the amide bond are a topic of fundamental interest in chemistry and biology. Herein, we report 17 O NMR and 15 N NMR spectroscopic data for four series of sterically-hindered acyclic amides. Despite the utility of 17 O NMR and 15 N NMR spectroscopy, these methods are severely underutilized in the experimental determination of electronic properties of the amide bond. The data demonstrate that a combined use of 17 O NMR and 15 N NMR serves as a powerful tool in assessing electronic effects of the amide bond substitution as a measure of electrophilicity of the amide bond. Notably, we demonstrate that steric destabilization of the amide bond results in electronically-activated amides that are comparable in terms of electrophilicity to acyl fluorides and carboxylic acid anhydrides. 

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2. N -Methylamino Pyrimidyl Amides (MAPA): Highly Reactive, Electronically-Activated Amides in Catalytic N–C(O) Cleavage

   https://doi.org/10.1021/acs.orglett.7b02288  

   Meng, Guangrong; Lalancette, Roger; Szostak, Roman; Szostak, Michal (August 2017, Organic Letters)
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   https://doi.org/10.1021/acs.orglett.1c01535  

   Rahman, Md. Mahbubur; Szostak, Michal (June 2021, Organic Letters)
4. Reversible Twisting of Primary Amides via Ground State N–C(O) Destabilization: Highly Twisted Rotationally Inverted Acyclic Amides

   https://doi.org/10.1021/jacs.7b11309  

   Meng, Guangrong; Shi, Shicheng; Lalancette, Roger; Szostak, Roman; Szostak, Michal (January 2018, Journal of the American Chemical Society)
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   https://doi.org/10.1039/D2CC02015G  

   Cabrera Allpas, Rodrigo; Hansen, Alexandar L.; Brüschweiler, Rafael (August 2022, Chemical Communications)

   An NMR supersequence is introduced for the rapid acquisition of 15 N-CEST and methyl- 13 C-CEST experiments in the same pulse sequence for applications to proteins. The high sensitivity and accuracy allows the simultaneous quantitative characterization of backbone and side-chain dynamics on the millisecond timescale ideal for routine screening for alternative protein states. 

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