A new cytotoxic plumbagin derivative from roots of Diospyros undulata.

A new plumbagin derivative, 3-(5-oxohexyl)plumbagin (1), together with six known benzoquinone derivatives (2-7), four known triterpenoids (8-11) and coniferyl aldehyde (12) were isolated from Diospyros undulata roots. Their structures were elucidated by intensive spectroscopy including 1 D and 2 D NMR, UV, IR and MS spectrometric analysis. Compound 1 exhibited strong cytotoxicity against three cancer cell lines as lung cancer (NCI-H187), breast cancer (MCF-7), and oral cancer (KB) with IC50 values of 7.16, 12.85 and 28.67 µM, respectively. Moreover, it did not showed cytotoxicity to Vero cells. In addition, the antimicrobial activity of compound 1 was moderate that kill only S. aureus with MBC of 250 µg/mL while other compounds especially compound 4 showed a broader activity that kill all tested bacteria.

Cytotoxic compounds from the stems of Diospyros ehretioides and their bioactivity.

A new (naphthalenyl)methyl acetate, (1,4,5-trimethoxynaphthalen-2-yl)methyl acetate (1) and (±)-4,5-dihydroxy-2-methyltetralone (2) were isolated together with five lupane triterpenes (3-7), naphthoquinone derivatives (8-13), coumarins (14 and 15) and a vanillic acid (16) from the stems of Diospyros ehretioides. Their structures were established through spectroscopic analysis, IR, 1D and 2D NMR. Both 1 and 2 displayed significant cytotoxicity against three cancer cell lines including HeLa, HCT116 and MCF-7, with IC50 values in the range of 5.05-15.90 µg/mL, while 16 exhibited moderate cytotoxicity against HeLa and HCT116 cell lines and was not toxic to Vero cells.

A 2H-tetrahydropyran derivative and bioactive constituents from the bark of Goniothalamus elegants Ast.

A new 2H-tetrahydropyran derivative, 6-epi-goniothalesdiol A (1), together with nine known styryllactones (2-10) and five known aristolactams (11-15) were isolated from the bark of Goniothalamus elegants Ast. The structures were elucidated by spectroscopic methods. The isolated compounds were evaluated for their cytotoxicity toward the KB, MCF7 and NCI-H187 cell lines as well as antimalarial and antimycobacterial activities. Compounds 4 and 10 showed strong activity against all three human cancer cell lines with IC50 values in the range of 0.538 to 4.25 µg/ml, while compounds 2, 4, 10 and 14 showed potent cytotoxicity against NCI-H187 with IC50 values in the range of 0.072 to 2.17 µg/ml. In addition, compounds 4, 6, 7, 9, 10 and 13 showed strong antiplasmodial activity with IC50 in the range of 2.28 to 5.89 µg/ml.

Diazido-bis(5,5'-dimethyl-2,2'-bipyridyl-κN,N')nickel(II) monohydrate.

In the crystal structure of the title compound, [Ni(N(3))(2)(C(12)H(12)N(2))(2)]·H(2)O, the Ni(II) atom is situated on a twofold axis and adopts a distorted octa-hedral geometry with the two 5,5'-dimethyl-2,2'-bipyridyl (dmbpy) and the two azide ligands in a cis arrangement. The water solvent mol-ecule is disordered over two positions in a 1:1 ratio.