BACKGROUND:Bursaphelenchus xylophilus, the causal agent of pine wilt disease, severely damages pine forests, and Bursaphelenchus mucronatus, a species related to B. xylophilus, is weakly pathogenic. Because the use of synthetic pesticides to control pine wilt disease has raised concerns for human and environmental health, a search for useful botanically based compounds is needed.RESULTS:The ethyl acetate layer from an ethanol extract of Stellera chamaejasme L. roots showed significant nematicidal activity against B. xylophilus and B. mucronatus, with LC50 values of 169.7 and 37.7 µg mL(-1), respectively, at 72 h. Further purification of the active layer yielded eight effective nematicidal compounds, which were identified by mass and nuclear magnetic resonance spectral data. Among the eight bioactive compounds, chamaejasmenin C induced the highest mortality against B. xylophilus, with an LC50 value of 2.7 µM at 72 h, and chamaechromone exhibited strong nematicidal activity against B. mucronatus, with an LC50 value of 0.003 µM at 72 h.CONCLUSION:The nematicidal metabolites from S. chamaejasme roots could be used as lead compounds for developing botanically based nematicides for the management of pine wilt disease.

以N-（2-羟丙基）甲基丙烯酰胺（HPMA），N-（3-氨基丙基）甲基丙烯酰胺（APMA）和全反式维甲酸（ATRA）为原料，采用自由基溶液聚合法设计合成P（HPMA-APMA）-ATRA，并用核磁共振氢谱对该化合物进行结构表征. 相比于单体ATRA，聚合物的水溶性显著增加，同时可通过胞吞作用进入细胞. 3-（4，5-二甲基噻唑-2）-2，5-二苯基四氮唑溴盐（MTT）法评估聚合物和单体ATRA对人早幼粒白血病细胞HL-60生长的抑制作用，流式细胞术检测两者对HL-60细胞周期分布及细胞表面抗原CD11b表达的影响，进一步结合氯化硝基四氮唑蓝（NBT）还原法评估聚合物诱导HL-60细胞分化的能力. 结果显示，聚合物比单体ATRA具有更强的细胞生长抑制活性，其IC 50 值分别为1.03和4.09 μmol/L；聚合物还具有更高的G 0 /G 1 期细胞阻滞效应，1.2 μmol/L时，聚合物比单体ATRA的G 0 /G 1 期细胞率高出17.7%；同样，0.4 μmol/L聚合物与2.4 μmol/L单体ATRA诱导HL-60的NBT还原能力相当，0.8 μmol/L聚合物与2.4 μmol/L单体ATRA诱导HL-60细胞表面抗原CD11b表达相当，表明聚合物比单体ATRA具有更强的诱导HL-60细胞向粒细胞分化的能力，其药效增强3~4倍.

A new ent-kaurane diterpenoid, Pseurata H (1), was isolated from the aerial parts of Rabdosia pseudo-irrorata C. Y. Wu, along with three known compounds, Pseurata B (2), Pseurata C (3) and Pseurata F (4). Their structures were established by extensive spectroscopic techniques (MS, IR, 1D and 2D NMR experiments).

Low-molecular-weight (LMW) chitosan salicylaldehyde Schiff-base and its zinc(II) complexes were synthesized and characterized by Fourier transform-infrared (FT-IR) spectra, transmission electron microscopy (TEM), dynamic light scattering (DLS), gel permeation chromatography-multiangle laser light scattering (GPC-MALLS), and elemental analysis. The results of electrophoretic analysis suggest that the Zn complexes bound to DNA by means of electrostatic interactions and intercalation. The effect of the Zn complexes on the growth of SMMC-7721 liver cancer cells was investigated by sulforhodamine B assay in vitro. The results reveal that the growth of liver cancer cells was inhibited by LMW-chitosan and their Zn complexes. The inhibition rate of the Zn complexes was higher than that of LMW-chitosan ligand. The LMW-chitosan Schiff-base Zn complex exhibited higher anticancer activity than the LMW-chitosan Zn complex. Combining LMW-chitosan with Schiff-base and Zn improved its anticancer activity, which we ascribe to the synergistic effect between the chitosan matrix and the planar construction of the Zn complexes.

The title compound glaucocalyxin A (1) (7, 14-dihydroxy-ent-kaur-16-en-3,15-dione) isolated from the leaves of isodon excisoides was characterized by IR, 1H NMR, 13C NMR, 1H-1H COSY, HMQC, HMBC, and EIMS, and its crystal structure was determined by single-crystal X-ray diffraction. The X-ray crystal structure revealed that the molecular backbone of the chosen crystal is a tetracyclic system, including three six-membered rings and a five-membered ring, and the three six-membered rings are in a chair-like conformation. The five-membered ring adopts a twisted envelope-like conformation, and its geometrical parameters were compared with theoretical calculations at the B3LYP and HF level of theory. The molecules form extensive networks through the intra- and intermolecular hydrogen bonds. The experimental NMR data were interpreted with the aid of magnetic shielding constant calculations, by means of the GIAO (gauge-lncluding atomic orbitals) method. Calculated and experimental results were compared with a satisfactory level of agreement. Molecular electrostatic potential map was used in an attempt to identify key features of the diterpenoid glaucocalyxin A that is necessary for its activity. Calculations of molecular electrostatic potential and stabilization energies suggest that the protonation of glaucocalyxin A will be able to occur on carbonyl oxygen atoms.

A new kind of nano-chitosan Schiff-base Cu complexes with particle sizes of 350 nm were prepared by combination of nano-chitosan, Cu and Schiff-base, and characterized by FT-IR spectra, TEM, DLS and elemental analysis. The modes and mechanism of interaction of the copper complexes with DNA were studied by the fluorescent probe method and electrophoresis analysis. The results suggest that the Cu complexes bound to DNA by electrostatic and intercalation modes. The anticancer activity of the Cu complexes was evaluated by Sulforhodamine B (SRB) assay in vitro. Nano-chitosan and their Schiff-base Cu complexes inhibited the growth of the liver cancer cell lines SMMC-7721 in vitro. The inhibition rate of Schiff-base Cu complexes was higher than that of nano-chitosan. Nano-chitosan combining with Schiff-base and Cu improved their anticancer activity, which ascribed to the synergistic effect between the chitosan matrix and the planar construction of the Cu complexes. Copyright (C) 2008 John Wiley & Sons, Ltd.

Three new solid complexes have been synthesized by the reaction of rare earth(III) nitrate with the first ligand curcumin (HL) and the second ligand 1,10-phenanthroline-5,6-dione (L′) in alcohol solution (pH = 6.5–7.0). The composition of the complexes has been characterized by elemental analysis, molar conductivity, thermogravimetric analysis, IR, UV–vis methods. The results reveal that β-diketone group of the first ligand to coordinates with rare earth ions in bidentate mode after deprotonated. But the second ligand uses its two N atoms coordinates with rare earth ions in bidentate mode. The general formula of the complexes is REL3L′ (RE = Sm, Eu, Dy). The results of antibacterial activity indicated that the complexes have excellent antibacterial ability for the testing bacterium than that of curcumin. The result of agarose gel electrophoresis suggested that the complex of SmL3L′ can cleave the plasmid DNA at physiological pH and temperature. And it was found that the cleavage process of plasmid DNA was sensitive to pH, however, adding radical scavengers almost had no effect on the DNA cleavage reaction, therefore, the cleavage of DNA by SmL3L′ does not produce diffusible hydroxyl radicals via the Fenton reaction.

6 beta,7 beta,14 beta-Trihydroxy-1 alpha-acetoxy-7 alpha,20-epoxy-ent-kaur-16-en-15-one was isolated from the natural plant of Isodon japonica (Burm.f), Haravar. galaucocalyx (maxim) Hara. The structure was elucidated by means of spectral and chemical studies. In addition, its crystal was determined by single-crystal X-ray diffraction analysis. It crystallizes in triclinic, space group P1, Z = 2, a = 6.3506(4), b = 13.5766(8), c = 15.2777(9) angstrom, alpha = 80.506(1), 83.856(1), gamma = 88.307(1)degrees, C25H36O9, M-r = 480.54, V = 1291.64(13) angstrom(3), Z = 2, D-c = 1.236 g/cm(3), F(000) = 516, mu = 0.093 mm(-1), S = 0.988, the final R = 0.0761 and wR = 0.1955. Flack factor is 0.02(19), and the largest peak and deepest hole on the final difference Fourier map are 0.556 and -0.265 e/angstrom(3), respectively. The X-ray diffraction shows the existence of intermolecular C-H center dot center dot center dot O (DA) hydrogen bonds between adjacent molecules.

A new ent-kaurane diterpenoid racemosin A (1) and three known compounds, leukamenin E (2), glaucocalyxin A (3) and wangzaozin A (4), have been isolated from the leaves of Isocion racemosa (Hemsl) Hara. The new diterpenoidis identified as 14β-hydroxy-3β, 7α-acetoxy-ent-kaur-16-en-15-one on the basis of spectral data, especially by 2D NMR techniques. Compounds 1-4 show significant cytotoxic activity against Bel-7402 and HO-8910 cells in the range of 1.51-2.57 and 3.33-4.02 μg/mL, respectively. This may be due to the presence of conjugated exo-methylene systen in an ent-kaurane skeleton.

The crystal structure of Wangzaozin A was elucidated on the basis of the single-crystal X-ray diffraction analysis. The X-ray crystal structure revealed that there were two molecules with a little difference in the bond lengths and bond angles data in least asymmetry unit, and three six-membered rings were in a chair-like conformation, five-membered rings adopted a twist envelope-like conformation in the compound, respectively. The crystal of the compound was in orthorhombic crystal system, space group P2(1)2(1)2(1) with accurate lattice constants as follows a = 0. 664 85 (8) nm, b = 2. 579 6 (4) nm, c = 1. 047 3(2) nm, Z = 4. The molecules formed extensive networks through the intra-molecular hydrogen bonds O3-H30 (...) O2, O3'-H30' (...) O2' and intermolecular hydrogen bonds O1-H10 (...) O3, O1'-H10'(...)O3', O2-H2O(...)O4', O2'-H20'(...)O4, and arranged along c axis in the crystal. The compound was found to exhibit a significant cytotoxicity against human tumor Bel-7402 and HO-8910 cells with (5.32 +/- 0.79) and (4.10 +/- 1.00) mu mol/L in SRB assay, respectively.

The new ent-kaurane diterpenoid weisiensin C (1) (1α,7α,14β ,18,20-pentahydroxy-ent-kaur-16- en-15-one), together with four known ent-kaurene diterpenoids, glaucocalyxin A (2), kamebanin (3), macrocalyxin D (4), and excisanin K (5), was isolated from the leaves of Isodon weisiensis C.Y. Wu. The structure of the new constituent (1) was elucidated by spectroscopic methods and confirmed by single-crystal X-ray diffraction.

AbstractFor Abstract see ChemInform Abstract in Full Text.

A new ent-kaurane diterpenoid, weisiensin B (1), was isolated from the leaves of Isodon weisiensis C. Y. Wu, along with four known ones, kamebanin (2), kamebacetal A (3), macrocalyxin D (4) and excisanin D (5). Their structures were determined by spectroscopic means. Compound 1-4 showed significant cytotoxic activity against Bel-7402 and HO-8910 cells.

Three new cytotoxic ent-kaurane diterpenoids, (1 alpha,7 alpha,14 beta)-1,7,14-trihydroxy-ent-kaur-16-en-15,18-dione (1), (1 alpha,7 alpha,140 beta)-1,7,14,18,20-pentahydroxy-ent-kaur-16-en-15-one (2), and (3 beta,7 alpha,14 beta)-3,7,14-tris(acetyloxy)ent-kaur-16-en-15-one (3), were isolated from Isodon weisiensis C. Y. Wu. Their structures were elucidated by spectroscopic methods, including 2D-NMR techniques, and the crystal structure of 1 was determined by single-crystal X-ray-diffraction analysis. The chosen crystal of 1 was orthorhombic, space group P2(1)2(1)2(1), and there were two molecules with little difference in bond length and bond angle in the least-asymmetry unit. Compounds 1-3 showed significant cytotoxic activities against human-cancer cell lines Bel-7402 and HO-8910.

A new ent-kaurane diterpenoid, excisoidesin (1), was isolated from the acetone extract of the leaves of isodon excisoides (Sun ex C. H. Hu) C. Y. Wu et H. W. Li, along with kamebacetal B (2), glaucocalyxin A (3), leukamenin E (4), kamebanin (5) and wangzaozin A (6). The structure of the new compound was determined as 7alpha,14beta,18-trihydroxy-ent-kaur-16-en-3,15-dione by spectroscopic methods. Compound 1-6 showed significant cytotoxic activity against human tumor Bel-7402 cells.