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Three new phlorizin derivatives, 6"-O-vanilloylphlorizin (1), 6"-O-(4-hydroxybenzoyl)phlorizin (2), 6"-O-feruloylphlorizin (3), along with four known dihydrochalcones, phlorizin (4), 3-hydroxyphlorizin, trilobatin, and 6"-O-acetylphlorizin were isolated from the leaves of Lithocarpus litseifolius. Their structures were established by analysis of extensive spectroscopic data. The new compounds were shown to be non-cytotoxic when tested against A549, HeLa, HepG2, and MCF-7 cell lines. [ABSTRACT FROM AUTHOR]

Two new coumarins, clauexcavatins A (1) and B (2), along with seven known ones (3–9), were isolated from the roots of Clausena excavata Burm. f. (Rutaceae). Their structures were elucidated on the basis of spectral data. [ABSTRACT FROM AUTHOR]

Four new metabolites M-1 [1,2,18,19-tetradehydro-4-demethyl-3,17-epoxy-7,20(2H,19H)-cyclovobasan], M-2 [1,2,4,21,18,19-hexadehydro-4-demethyl-3,17-epoxy-7,20(2H,19H)-cyclovobasan], M-3 [1,2,18,19-tetradehydro-4-demethyl-4-formaldehyde-3,17-epoxy-7,20(2H,19H)-cyclovobasan], and M-4 [1,2,4,21,18,19-hexadehydro-4-demethyl-4-oxy-3,17-epoxy-7,20(2H,19H)-cyclovobasan] were isolated from the chloroform extract of koumine incubated with phenobarbital-treated rat liver microsomes. The structures of M-1, M-2, M-3, and M-4 were elucidated by spectroscopic methods including ESI-TOF-MS, 1D, and 2D NMR experiments. The metabolic pathway of koumine was proposed. The cytotoxic activities between koumine and its metabolites were also compared in the A549 cell line. [ABSTRACT FROM AUTHOR]

Reaction of ethyl anthranilate, sodium nitrite, and 2-aminobenzothiazole produces a new triazenide compound, 1-[(2-carboxyethyl)benzene]-3-[benzothiazole]triazene (HL), which has been characterized by X-ray crystallography and NMR spectrum. In the presence of Et3N, reaction of HL and CuCl2 · 2H2O or CoCl2 · 6H2O in THF/methanol affords a tetranuclear copper(II) complex [Cu4L4(µ-OMe)4] · 4THF (1) and a cobalt(III) complex [CoL'3] (2) (L' is 1-[benzothiazole] triazene ion), accompanied by C-N bond cleavage of HL. They are characterized by X-ray crystallography and magnetic susceptibility measurement. Magnetic studies indicate significant antiferromagnetic coupling between the copper(II) centers for 1. The value obtained for the coupling constant J is -585 cm-1. [ABSTRACT FROM AUTHOR]