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1. In Situ Quantification of Biological N ₂ Production Using Naturally Occurring ¹⁵ N ¹⁵ N

   https://doi.org/10.1021/acs.est.9b00812  

   Yeung, Laurence Y.; Haslun, Joshua A.; Ostrom, Nathaniel E.; Sun, Tao; Young, Edward D.; van Kessel, Maartje A. H. J.; Lücker, Sebastian; Jetten, Mike S. M. (April 2019, Environmental Science & Technology)
2. Solvent Effects in Hyperpolarization of ¹⁵ N Nuclei in [ ¹⁵ N ₃ ]Metronidazole and [ ¹⁵ N ₃ ]Nimorazole Antibiotics via SABRE‐SHEATH**

   https://doi.org/10.1002/anse.202400045  

   Yi, Anna_P; Salnikov, Oleg_G; Burueva, Dudari_B; Chukanov, Nikita_V; Chekmenev, Eduard_Y; Koptyug, Igor_V (August 2024, Analysis & Sensing)

   Abstract Metronidazole and nimorazole are antibiotics of a nitroimidazole group which also may be potentially utilized as hypoxia radiosensitizers for the treatment of cancerous tumors. Hyperpolarization of¹⁵N nuclei in these compounds using SABRE‐SHEATH (Signal Amplification By Reversible Exchange in SHield Enables Alignment Transfer to Heteronuclei) approach provides dramatic enhancement of detection sensitivity of these analytes using magnetic resonance spectroscopy and imaging. Methanol‐d₄is conventionally employed as a solvent in SABRE hyperpolarization process. Herein, we investigate SABRE‐SHEATH hyperpolarization of isotopically labeled [¹⁵N₃]metronidazole and [¹⁵N₃]nimorazole in nondeuterated methanol and ethanol solvents. Optimization of such hyperpolarization parameters as polarization transfer magnetic field, temperature, parahydrogen flow rate and pressure allowed us to obtain an average¹⁵N polarization of up to 7.2–7.4 % for both substrates. The highest¹⁵N polarizations were observed in methanol‐d₄for [¹⁵N₃]metronidazole and in ethanol for [¹⁵N₃]nimorazole. At a clinically relevant magnetic field of 1.4 T the¹⁵N nuclei of these substrates possess long characteristic hyperpolarization lifetimes (T₁) of ca. 1 to ca. 7 min. This study represents a major step toward SABRE in more biocompatible solvents, such as ethanol, and also paves the way for future utilization of these hyperpolarized nitroimidazoles as molecular contrast agents for MRI visualization of tumors. 

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3. Redox Studies of the Scandium Metallocene (C ₅ H ₂ ^t Bu ₃ ) ₂ Sc ^II Lead to a Terminal Side-On (N═N) ^2– Complex: [(C ₅ H ₂ ^t Bu ₃ ) ₂ Sc ^III (η ² -N ₂ )] ⁻

   https://doi.org/10.1021/jacs.5c00607  

   Queen, Joshua D; Rajabi, Ahmadreza; Ziller, Joseph W; Furche, Filipp; Evans, William J (April 2025, Journal of the American Chemical Society)
4. Solid-State End-On to Side-On Isomerization of (N═N) ^2– in {[(R ₂ N) ₃ Nd] ₂ N ₂ } ^2– (R = SiMe ₃ ) Connects In Situ Ln ^III (NR ₂ ) ₃ /K and Isolated [Ln ^II (NR ₂ ) ₃ ] ^1– Dinitrogen Reduction

   https://doi.org/10.1021/jacs.2c06716  

   Chung, Amanda B.; Rappoport, Dmitrij; Ziller, Joseph W.; Cramer, Roger E.; Furche, Filipp; Evans, William J. (September 2022, Journal of the American Chemical Society)
5. Formation of the End-on Bound Lanthanide Dinitrogen Complexes [(R ₂ N) ₃ Ln–N═N–Ln(NR ₂ ) ₃ ] ^2– from Divalent [(R ₂ N) ₃ Ln] ^1– Salts (R = SiMe ₃ )

   https://doi.org/10.1021/jacs.0c01021  

   Ryan, Austin J.; Balasubramani, Sree ganesh; Ziller, Joseph W.; Furche, Filipp; Evans, William J. (May 2020, Journal of the American Chemical Society)

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