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171.
Methyl pheophorbide-a/a′ derivatives covalently linked with oligomethylene chains at the 3-CH2OCO– and 132-COO– moieties in a molecule were prepared by modifying chlorophyll-a through intramolecular ring-closing metathesis of vinyl groups. At least, a C10-length between the 33- and 134-positions was necessary for the cyclization and connection of a C12-strap was the most suitable to achieve the highest closure yield. The oligomethylene chain in 132 R-epimers derived from methyl pheophorbide-a covered the α-face of the chlorin π-plane and the strap in the corresponding 132 S-epimers protected the β-face. Synthetic 132 R-epimer with a dodecamethylene chain gave a flat chlorin π-plane, while the decamethylene chain in the 132 R-epimer distorted the π-system due to its shorter linkage. The distortion by strapping in the 132 R-epimer induced a slight blue-shift of Qy peak in dichloromethane. CD spectra of the 132 R-epimers were similarly dependent on the chain length, i.e., the distortion of π-plane. Visible absorption and CD spectra of all the strapped 132 S-epimers were almost identical and only slightly different from those of the unstrapped. The strapping in the 132 S-epimers shifted the Qy peak bathochromically. 相似文献
172.
Satoshi N. Suzuki Masae I. Ishihara Masahiro Nakamura Shin Abe Tsutom Hiura Kosuke Homma Motoki Higa Daisuke Hoshino Kazuhiko Hoshizaki Hideyuki Ida Ken Ishida Motohiro Kawanishi Kazutaka Kobayashi Koichiro Kuraji Shigeo Kuramoto Takashi Masaki Kaoru Niiyama Mahoko Noguchi Haruto Nomiya Satoshi Saito Takeshi Sakai Michinori Sakimoto Hitoshi Sakio Tamotsu Sato Hirofumi Shibano Mitsue Shibata Maki Suzuki Atsushi Takashima Hiroshi Tanaka Masahiro Takagi Naoaki Tashiro Naoko Tokuchi Toshiya Yoshida Yumiko Yoshida 《Ecological Research》2012,27(6):989-990
This data paper reports litter fall data collected in a network of 21 forest sites in Japan. This is the largest litter fall data set freely available in Japan to date. The network is a part of the Monitoring Sites 1000 Project launched by the Ministry of the Environment, Japan. It covers subarctic to subtropical climate zones and the four major forest types in Japan. Twenty-three permanent plots in which usually 25 litter traps were installed were established in old-growth or secondary natural forests. Litter falls were collected monthly from 2004, and sorted into leaves, branches, reproductive structures and miscellaneous. The data provide seasonal patterns and inter-annual dynamics of litter falls, and their geographical patterns, and offer good opportunities for meta-analyses and comparative studies among forests. 相似文献
173.
Estrogen-like activity and dual roles in cell signaling of an Agaricus blazei Murrill mycelia-dikaryon extract 总被引:1,自引:0,他引:1
174.
Fuchi N Iura Y Kaneko H Nitta A Suyama K Ueda H Yamaguchi S Nishimura K Fujii S Sekiya Y Yamada M Takahashi T 《Bioorganic & medicinal chemistry letters》2012,22(13):4358-4361
We report the discovery and structure-activity relationship of 2,6-disubstituted pyrazines, which are potent and selective CK2 inhibitors. Lead compound 1 was identified, and derivatives were prepared to develop potent inhibitory activity. As a result, we obtained compound 7, which was the smallest unit that retained potency. Then, introducing an aminoalkyl group at the 6-position of the indazole ring resulted in improved efficacy in both enzymatic and cell-based CK2 inhibition assays. Moreover, compound 13 showed selectivity against other kinases and in vivo efficacy in a rat nephritis model. These results show that 2,6-disubstituted pyrazines have potential as therapeutic agents for nephritis. 相似文献
175.
T Taguchi T Ebihara A Furukawa Y Hidaka R Ariga S Okamoto K Ichinose 《Bioorganic & medicinal chemistry letters》2012,22(15):5041-5045
An oxygenated derivative of dihydrokalafungin (DHK) was isolated from a deletion mutant of the actVA-ORF4 gene involved in the biosynthesis of a dimeric benzoisochromanequinone (BIQ) antibiotic, actinorhodin (ACT), in Streptomyces coelicolor A3(2). Spectroscopic analysis elucidated its structure as 8-hydroxy-DHK, corresponding to the monomeric unit of ACT. Further metabolite analysis identified its related compound, clearly derived from the reduction of 8-hydroxy-DHK. The structures of these metabolites indicate the essential role of ActVA-ORF4 in ACT biosynthesis, specifically in dimerization of a BIQ intermediate via C-C bond formation. 相似文献
176.
177.
Wada Y Cardinale I Khatcherian A Chu J Kantor AB Gottlieb AB Tatsuta N Jacobson E Barsoum J Krueger JG 《PloS one》2012,7(4):e35069
Psoriasis is characterized by hyperplasia of the epidermis and infiltration of leukocytes into both the dermis and epidermis. IL-23, a key cytokine that induces T(H)17 cells, has been found to play a critical role in the pathogenesis of psoriasis. Apilimod is a small-molecule compound that selectively suppresses synthesis of IL-12 and IL-23. An open-label clinical study of oral administration of apilimod was conducted in patients with psoriasis. Substantial improvements in histology and clinical measurements were observed in patients receiving 70 mg QD. The expression of IL-23p19 and IL-12/IL-23p40 in skin lesions was significantly reduced in this dose group, with a simultaneous increase in IL-10 observed. A decrease in the levels of T(H)1 and T(H)17 cytokines/chemokines in skin lesions followed these p19 and p40 changes. In parallel, a reduction in skin-infiltrating CD11c(+) dendritic cells and CD3(+) T cells was seen, with a greater decrease in the CD11c(+) population. This was accompanied by increases in T and B cells, and decreases in neutrophils and eosinophils in the periphery. This study demonstrates the immunomodulatory activity of apilimod and provides clinical evidence supporting the inhibition of IL-12/IL-23 synthesis for the treatment of T(H)1- and T(H)17-mediated inflammatory diseases. 相似文献
178.
179.
Takasu Nana N. Takenaka Yumiko Fujiwara Makiko Toichi Motomi 《Sleep and biological rhythms》2012,10(2):84-93
Sleep and Biological Rhythms - The present study examined the effects of regularizing sleep-wake schedules on sleep, autonomic function and mood/emotional and personality states in 14 habitually... 相似文献
180.
Eguchi K Manabe I Oishi-Tanaka Y Ohsugi M Kono N Ogata F Yagi N Ohto U Kimoto M Miyake K Tobe K Arai H Kadowaki T Nagai R 《Cell metabolism》2012,15(4):518-533
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