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Phytochemical investigation on the stems of Schisandra glaucescens resulted into the isolation of three new lanostane triterpenoids, 12-hydroxyschiglausin B (1), 12-hydroxykadsuphilactone B (2), and 20R-hydroxyschinalactone C (3). Structural elucidation of all the compounds was accomplished by spectral methods. The isolated compounds were tested in vitro for cytotoxic activities. As a result, triterpenoids 1 and 2 showed cytotoxic activities for all six tested tumor cell lines with IC50 values less than 15 μM. [ABSTRACT FROM AUTHOR]

Five new phorbol esters, (four phorbol diesters, 1 – 4 , and one 4-deoxy-4α-phorbol diester, 5 ), as well as four known phorbol esters analogues ( 6 – 9 ) were isolated and identified from the branches and leaves of Croton tiglium . Their structures were elucidated mainly by extensive NMR spectroscopic, and mass spectrometric analysis. Among them, compound ( 1 ) was the first example of a naturally occurring phorbol ester with the 20-aldehyde group. Compounds 2 – 5 , and 7 – 9 showed potent cytotoxicity against the K562, A549, DU145, H1975, MCF-7, U937, SGC-7901, HL60, Hela, and MOLT-4 cell lines, with IC 50 values ranging from 1.0 to 43 μM, while none of the compounds exhibited cytotoxic effects on normal human cell lines 293T and LX-2, respectively. In addition, compound 3 exhibited moderate COX-1 and COX-2 inhibition, with IC 50 values of 0.14 and 8.5 μM, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Three new copper(II) complexes of 5-pyridin-2-yl-[1,3]dioxolo[4,5-g]isoquinoline (PYP), i.e. [Cu2(PYP)2Cl4] (1), [Cu4(PYP)4(ClO4)2(H2O)2](ClO4)2·2H2O (2), and [Cu2(PYP)2Cl4] n (3), were synthesized and fully characterized. In comparison to free PYP, complexes 1–3 exhibited enhanced cytotoxicity against tested human tumor cell lines BEL-7404, SK-OV-3, A549, A375, MGC-803 and NCI-H460, with IC50 values ranging from 0.31 to 30.76 μM. Complexes 1–3 exhibited lower cytotoxicity to HL-7702 than them to cancer cells. Complex 1 induced apoptotic death of BEL-7404, which involved mitochondria in the process. Caspase-3 activation assay indicated that 1 could be an efficient activator of caspase-3. DNA binding studies by UV–vis, DNA-melting, competitive binding, CD, viscosity measurement and agarose gel electrophoresis, revealed that intercalation might be the most likely binding mode of 1 with DNA. [Copyright &y& Elsevier]