Grindelane diterpenoids from Stevia subpubescens.
Four new 9R,13R-epoxylabdane diterpenes (1-4) and a known clerodane derivative, 3,4beta-epoxy-5beta,10beta-cis-17alpha, 20alpha-clerod-13(14)-en-15,16-olide, were isolated from the leaves of Stevia subpubescens. The structures, which correspond to the grindelane class of diterpenoids, were elucidated by NMR data, chemical correlation, and single-crystal X-ray diffraction analysis of monoacetate 5. The absolute configuration of 1-4 is based on the optical activity of ketone 3 as compared with data of closely related substances.
Román
L U
LU
Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Apartado 137, Morelia, Michoacán, 58000 México.
Cambrón
J I
JI
del Río
R E
RE
Hernández
J D
JD
Cerda-García-Rojas
C M
CM
Joseph-Nathan
P
P
D000107:Acetylation; D019659:Asteraceae / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004224:Diterpenes / Q000737:chemistry*; D006868:Hydrolysis; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D010084:Oxidation-Reduction; D010936:Plant Extracts / Q000737:chemistry; D018515:Plant Leaves / Q000737:chemistry; D013055:Spectrophotometry, Infrared
D004224:Diterpenes; D010936:Plant Extracts