Publications by authors named "Kai-Bai Yu"

Two new phthalide dimers, namely chuanxiongnolide A (1) and chuanxiongnolide B (2), along with eleven known phthalides and derivatives ( 3 - 13), were isolated from the roots of Ligusticum chuanxiong Hort. (Umbelliferae). The chemical structures of the new compounds were established by HR-ESI-MS, 1D- and 2D-NMR spectroscopic analysis, whilst the relative stereochemistry of 1 was confirmed by X-ray crystallographic data.

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Three new diterpene alkaloids, 16,17-dihydro-12 beta,16 beta-epoxynapelline (1), N-deethyl- N-methyl-12-epi-napelline (2) and 11- epi-16 alpha,17-dihydroxylepenine (3), along with twenty-six known alkaloids (4 - 29) were isolated from the roots of Aconitum nagarum var. lasiandrum. The chemical structures of the new compounds were established by HR-MS as well as 1D- and 2D-NMR spectroscopic analysis.

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The title compound, 5-hydroxy-4',7-dimethoxyisoflavone, C17H14O5, is composed of a benzopyranone moiety, a phenyl moiety and two methoxy groups. The benzopyranone ring is not coplanar with the phenyl ring, the dihedral angle between them being 56.28 (3) degrees.

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