Synthesis of Sterically Shielded Nitroxides Using the Reaction of Nitrones with Alkynylmagnesium Bromides

Synthesis of Sterically Shielded Nitroxides Using the Reaction of Nitrones with Alkynylmagnesium Bromides Full article

Journal

Molecules
, E-ISSN: 1420-3049

Output data

Year: 2022, Volume: 27, Number: 21, Pages: 7626 Pages count : 1 DOI: 10.3390/molecules27217626

Authors

Dobrynin Sergey A. ¹ , Gulman Mark M. ^1,2 , Morozov Denis A. ¹ , Zhurko Irina F. ¹ , Taratayko Andrey I. ^1,2 , Sotnikova Yulia S. ¹ , Glazachev Yurii I. ³ , Gatilov Yuri V. ¹ , Kirilyuk Igor A. ¹

Affiliations

1	N. N. Vorozhtsov Novosibirsk Institute of Organic Chemistry SB RAS, Lavrentiev Ave. 9, 630090 Novosibirsk, Russia
2	Department of Natural Sciences, Novosibirsk State University, Pirogova Str. 2, 630090 Novosibirsk, Russia
3	Voevodsky Institute of Chemical Kinetics and Combustion SB RAS, Institutskaya 3, 630090 Novosibirsk, Russia

Sterically shielded nitroxides, which demonstrate high resistance to bioreduction, are the spin labels of choice for structural studies inside living cells using pulsed EPR and functional MRI and EPRI in vivo. To prepare new sterically shielded nitroxides, a reaction of cyclic nitrones, including various 1-pyrroline-1-oxides, 2,5-dihydroimidazole-3-oxide and 4H-imidazole-3-oxide with alkynylmagnesium bromide wereused. The reaction gave corresponding nitroxides with an alkynyl group adjacent to the N-O moiety. The hydrogenation of resulting 2-ethynyl-substituted nitroxides with subsequent re-oxidation of the N-OH group produced the corresponding sterically shielded tetraalkylnitroxides of pyrrolidine, imidazolidine and 2,5-dihydroimidazole series. EPR studies revealed large additional couplings up to 4 G in the spectra of pyrrolidine and imidazolidine nitroxides with substituents in 3- and/or 4-positions of the ring.

Dobrynin S.A. , Gulman M.M. , Morozov D.A. , Zhurko I.F. , Taratayko A.I. , Sotnikova Y.S. , Glazachev Y.I. , Gatilov Y.V. , Kirilyuk I.A.
Synthesis of Sterically Shielded Nitroxides Using the Reaction of Nitrones with Alkynylmagnesium Bromides
Molecules. 2022. V.27. N21. P.7626. DOI: 10.3390/molecules27217626 WOS

Submitted:	Oct 3, 2022
Accepted:	Nov 3, 2022
Published online:	Nov 7, 2022

Web of science	WOS:000883610800001
OpenAlex	W4308531239