Solution- and solid-state structures of the (-)-n-heptylcarbamate of geneseroline and its hydrochloride salt.
The solid state structures of the (-)-n-heptylcarbamate of geneseroline and its hydrochloride salt were determined by single crystal X-ray diffraction analysis. Both compounds gave crystals belonging to the orthorombic P2(1)2(1)2(1) space group with a = 27.597(7) A, b = 8.899(2) A, c = 9.290(2) A, V = 2281.5(9) A3, Z = 4, and R = 0.0682 for the base and a = 11.300(1) A, b = 8.3485(5) A, c = 24.141(2) A, V = 2277.3(3) A3, Z = 4, and R = 0.0482 for the salt. X-ray and 1H NMR analysis revealed that the base is a 1,2-oxazine derivative. The six-membered ring adopts a 4C1 chair conformation in the solid-state, whereas, in CDCl3 solution, it exists as a mixture of two possible chair conformers, 4C1 and 1C4, with the N-methyl group in the equatorial position (ratio approximately 75:25). The salt is an N-oxide derivative; the five-membered ring adopts different envelope conformations in the solid-state and in CDCl3 solution, suggesting a certain flexibility. In more polar solvents, the salt partially undergoes fast inversion at the tetrahedral nitrogen, giving rise to the corresponding epimer.
Redenti
E
E
Chemical and Biopharmaceutical Department, Chiesi Farmaceutici S.p.A., Parma, Italy.
Delcanale
M
M
Amari
G
G
Ventura
P
P
Bacchi
A
A
Pelizzi
G
G
D000470:Alkaloids / Q000138:chemical synthesis* / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D008968:Molecular Conformation; D012996:Solutions; D014961:X-Ray Diffraction
D000470:Alkaloids; D012996:Solutions; C060404:geneseroline