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391.
Noriyuki Hatae Jun Nakamura Tetsuo Okujima Minoru Ishikura Takumi Abe Satoshi Hibino Tominari Choshi Chiaki Okada Hiroko Yamada Hidemitsu Uno Eiko Toyota 《Bioorganic & medicinal chemistry letters》2013,23(16):4637-4640
9,10-Phenanthrenequinone (9,10-PQ) is one of the most abundant quinones among diesel exhaust particulates. Recent data have suggested that quinones induce apoptosis in immune, epithelial and tumor cells, leading to respirator illness; however, the mechanisms by which quinones induce apoptosis and the structure required for this remain unknown. We studied the antitumor activity of 9,10-PQ analogs against two human tumor cell lines, HCT-116 colon tumor cells and HL-60 promyelocytic leukemia cells. The loss of the cis-orthoquinone unit in 9,10-PQ abrogated its ability to induce apoptosis in the two tumor cell lines, and the LC50 values of these analogs were indicated over 10 μM. An analog of 9,10-PQ in which the biaryl unit had been deleted displayed a reduced ability to induce tumor cell apoptosis, while the analogs 1,10-phenanthroline-5,6-dione (9) and pyrene-4,5-dione (10), which also had modified biaryl units, exhibited increased tumor cell apoptotic activity. The cis-orthoquinone unit in 9,10-PQ was identified as essential for its ability to induce apoptosis in tumor cells, and its biaryl unit is also considered to influence orthoquinone-mediated apoptotic activity. 相似文献
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Biljana Vidović Vida Jojić Ivana Marić Slavica Marinković Richard Hansen Radmila Petanović 《Experimental & applied acarology》2014,64(3):321-335
The russet mite, Aceria anthocoptes (Nalepa), is the only eriophyoid that has been recorded on Cirsium arvense (L.) Scop. It has been noted in several European countries and recently in the USA. In this study we explored the geographic and host-related variability of Aceria spp. inhabiting different Cirsium spp. We applied landmark-based geometric morphometric methods to study morphological variability of three body regions (ventral, coxigenital and prodorsal) of 13 Aceria spp. populations inhabiting five Cirsium spp. in Serbia (Europe) and four Cirsium spp. in Colorado (North America). Analyses of size and shape variation revealed statistically significant differences between Aceria spp. living on European native and North American native Cirsium spp., as well as between A. anthocoptes s.s. inhabiting European C. arvense and North American C. arvense. The coxigenital region was the most informative when considering inter-population shape differences. European Aceria spp. dwelling on Cirsium spp., including A. anthocoptes s.s. from C. arvense, are characterized by higher inter-population size and shape variability than their North American counterparts. This finding supports a Eurasian origin of A. anthocoptes, presumed to consist of a complex of cryptic taxa probably coevolved with host plants in the native environment. Morphological similarity among Aceria spp. inhabiting North American native Cirsium spp. may indicate that speciation of A. anthocoptes started relatively soon after the host shift to plants different from C. arvense in the invaded region. 相似文献
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Synthesis of chiral compounds derived from salicylaldehyde and pyridoxal was carried out. In aqueous media containing copper ion, these compounds were analyzed to form Schiff base copper chelate spontaneously with α-amino acid. This complex formation process was reversed by the addition of EDTA. Applicabilities of the compounds to the resolution of α-amino acids are discussed. 相似文献
397.
Yoshinori Asakawa Keiko Takikawa Masao Toyota Tsunematsu Takemoto 《Phytochemistry》1982,21(10):2481-2490
Four novel prenyl bibenzyls, perrottetin A–D were isolated from the liverwort Radula perrottetii together with a new sesquiterpene phenol, ent-2, 3-dihydroxycuparene and a prenyl dihydrochalcone, and their structures were determined by spectral methods and chemical transformations. Further investigation of the French species R. complanata resulted in the isolation of four new bibenzyls, 3, 4′-dimethoxybibenzyl, 3,5-dihydroxy-4-(2, 3-epoxy-3-methylbutyl)bibenzyl, radulanin H and radulanolide. R. buccinifera was chemically close to R. complanata. The composition of bibenzyls found in R. perrottetii and R. oyamensis were different from that of the other Radula species referred to in the section Radula. Some prenyl bibenzyls showed antimicrobial activity against Streptococcus aureus (20 μg/ml). The allergenic activity of R. complanata is due to (+)-frullanolide from the liverwort Frullania dilatata which is intermingled in R. complanata. 相似文献
398.
Reinvestigation of a Japanese sample of the thalloid liverwort Conocephalum conicum afforded (+)-bornyl ferulate and bornyl 2 - methoxy - 4 - hydroxycinnamate together with (?) - limonene, (?) - β - sabinene, (+) - bicycloelemene, (+) - β - elemene, (?) - bicyclogermacrene, lunularin, and the two compounds, 1 - octen - 3 - ol and 1 - octen - 3 - yl acetate, responsible for the mushroom-like odour of the crushed thallus. The chirality of the compounds isolated is discussed. 相似文献
399.
Abstract Population dynamics of Fusarium oxysporum f. sp. raphani PEG-4 with a resistant marker to antibiotic hygromycin B was investigated in soils of different fungistatic capacity. Germination of PEG-4 was significantly higher in a soil amended with chemical fertilizer (CF-soil) than in a soil amended with farmyard manure (FYM-soil). Thus it was concluded that CF-soil was weakly fungistatic, and FYM-soil was strongly so. The fates of PEG-4 spores in the soils were similar when PEG-4 was introduced at initial densities of 1 101 to 107 g−1 . However, alteration of environmental conditions, which might induce the germination of PEG-4 spores, resulted in the soils having different effects on the fate of PEG-4. Survival of PEG-4 in CF-soil increased compared with that in control conditions, but that in FYM-soil decreased. 相似文献
400.