02034nas a2200205 4500008004100000245013200041210006900173260000800242300001500250490000600265520125700271100004001528700001401568700002901582700001901611700001801630700002401648700002601672856013001698 2025 eng d00aGraphene oxide-cyclopentylamine (GO-d-CP) liquid crystals as a novel alignment medium for anisotropic nmr with analyte recovery0 aGraphene oxidecyclopentylamine GOdCP liquid crystals as a novel  cAPR ae2024000390 v53 a

In this study, we present graphene oxide derivatized with cyclopentylamine (GO-d-CP) as a DMSO-compatible liquid crystal alignment medium that is free from any background NMR signal for application in anisotropic NMR. This novel alignment medium facilitates optimal isotropic and anisotropic conditions within a single sample preparation, controlled by sonication, thereby enabling the measurement of anisotropic NMR parameters- residual dipolar couplings (RDC) and residual chemical shift anisotropy (RCSA). GO-d-CP offers several advantages, including ease of synthesis, isolation of solid GO-d-CP as a stable non-hygroscopic material, and maintenance of the anisotropic state stability >30 days, allowing for prolonged and repetitive experiments. Notably, post the analysis it allows for easy recovery of valuable analytes as well as GO-d-CP for reuse, enabling the routine application of anisotropic NMR in structural analysis of small molecules. We demonstrate its efficacy by analyzing the relative stereochemistry of four compounds - estrone, santonin, griseofulvin, and cinmethylin - using anisotropic NMR data.

1 aJatheendranath, Sandesh, Chickmagal1 aDas, Akhi1 aDeshpande, Sudhindra, H.1 aNath, Nilamoni1 aMaier, Walter1 aStreitferdt, Verena1 aMarelli, Udaya, Kiran uhttps://library.ncl.res.in/content/graphene-oxide-cyclopentylamine-go-d-cp-liquid-crystals-novel-alignment-medium-anisotropic