Signal Amplification by Reversible Exchange (SABRE) technique enables nuclear spin hyperpolarization of wide range of compounds using parahydrogen. Here we present the synthetic approach to prepare15N‐labeled [15N]dalfampridine (4‐amino[15N]pyridine) utilized as a drug to reduce the symptoms of multiple sclerosis. The synthesized compound was hyperpolarized using SABRE at microtesla magnetic fields (SABRE‐SHEATH technique) with up to 2.0 %15N polarization. The 7‐hour‐long activation of SABRE pre‐catalyst [Ir(IMes)(COD)Cl] in the presence of [15N]dalfampridine can be remedied by the use of pyridine co‐ligand for catalyst activation while retaining the15N polarization levels of [15N]dalfampridine. The effects of experimental conditions such as polarization transfer magnetic field, temperature, concentration, parahydrogen flow rate and pressure on15N polarization levels of free and equatorial catalyst‐bound [15N]dalfampridine were investigated. Moreover, we studied15N polarization build‐up and decay at magnetic field of less than 0.04 μT as well as15N polarization decay at the Earth's magnetic field and at 1.4 T.
NMR hyperpolarization techniques enhance nuclear spin polarization by several orders of magnitude resulting in corresponding sensitivity gains. This enormous sensitivity gain enables new applications ranging from studies of small molecules by using high‐resolution NMR spectroscopy to real‐time metabolic imaging
- Award ID(s):
- 1904780
- NSF-PAR ID:
- 10230269
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Chemistry – A European Journal
- Volume:
- 27
- Issue:
- 38
- ISSN:
- 0947-6539
- Format(s):
- Medium: X Size: p. 9727-9736
- Size(s):
- ["p. 9727-9736"]
- Sponsoring Org:
- National Science Foundation
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