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.
Chemical and Biopharmaceutical Department, Chiesi Farmaceutici S.p.A., Parma, Italy.
E
E
Redenti
M
M
Delcanale
G
G
Amari
P
P
Ventura
A
A
Bacchi
G
G
Pelizzi
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