The conformational space of the antioxidant dihydrolipoic acid has been explored through the investigation of its pharmacophore 1,3-propanedithiol. Five of the possible 25 non equivalent isomers (namely: gGGg’, gGGg, g’AGg, gAGg and g’AGg’) were observed in the 59.6-74.4 GHz frequency region by free-jet absorption rotational spectroscopy and for three of them also the 34S mono-substituted isotopologues were detected in natural abundance. Theoretical simulations show that the balance of steric and electronic intramolecular interactions arises on a shallow conformational potential energy surface and suggest that in polar solvents the dithiol chain’s flexibility is greater than in the isolated phase.
On the torsional flexibility of the dihydrolipoic acid's pharmacophore: 1,3-propanedithiol / Vigorito, Annalisa; Calabrese, Camilla; Paltanin, Ettore; Melandri, Sonia; Maris, Assimo. - In: PHYSICAL CHEMISTRY CHEMICAL PHYSICS. - ISSN 1463-9076. - STAMPA. - 19:1(2017), pp. 496-502. [10.1039/C6CP05606G]
On the torsional flexibility of the dihydrolipoic acid's pharmacophore: 1,3-propanedithiol
VIGORITO, ANNALISA;CALABRESE, CAMILLA;PALTANIN, ETTORE;MELANDRI, SONIA;MARIS, ASSIMO
2017
Abstract
The conformational space of the antioxidant dihydrolipoic acid has been explored through the investigation of its pharmacophore 1,3-propanedithiol. Five of the possible 25 non equivalent isomers (namely: gGGg’, gGGg, g’AGg, gAGg and g’AGg’) were observed in the 59.6-74.4 GHz frequency region by free-jet absorption rotational spectroscopy and for three of them also the 34S mono-substituted isotopologues were detected in natural abundance. Theoretical simulations show that the balance of steric and electronic intramolecular interactions arises on a shallow conformational potential energy surface and suggest that in polar solvents the dithiol chain’s flexibility is greater than in the isolated phase.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
