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41.
42.
Ayato Sato Kosuke Dodo Makoto Makishima Yuichi Hashimoto Mikiko Sodeoka 《Bioorganic & medicinal chemistry letters》2013,23(10):3013-3017
2,3-Dinorprostaglandins (dinor-PGs) have been regarded as β-oxidation products of arachidonic-acid-derived prostaglandins, but their biological activities in mammalian cells remain unclear. On the other hand, C18 polyunsaturated fatty acids (PUFAs), such as γ-linolenic acid (GLA), have various biological activities, and dinor-PGs are speculated to be biosynthesized from GLA. Here, we synthesized dinor-PGs that may possibly be derived from GLA and examined their activities towards peroxisome proliferator-activated receptors (PPARs). Dinor-PGD1 (1) and its epimer 13-epi-dinor-PGD1 (epi-1) were found to be dual agonists for PPARα/γ, whereas PGD2 derived from arachidonic acid is selective for PPARγ. Thus, GLA-derived dinor-PGs may have unique biological roles. 相似文献
43.
Hitoshi Tamiaki Meiyun Xu Takuya Tanaka Tadashi Mizoguchi 《Bioorganic & medicinal chemistry letters》2013,23(8):2377-2379
When a pyridine solution of zinc methyl 8-vinyl-mesopyropheophorbide-a was irradiated with visible light in the presence of ethanol, ascorbic acid and diazabicylo[2.2.2]octane under nitrogen at room temperature, zinc (7R/S,8E)-8-ethylidene-bacteriochlorin was obtained via 1,4-hydrogenation. The 1,4-photoreduction is similar to the enzymatic reduction of 8-vinyl-chlorophyllides to (E)-8-ethylidene-bacteriochlorins in anoxygenic photosynthetic bacteria producing bacteriochlorophylls-b/g. The resulting zinc 8-ethylidene-bacteriochlorin was readily isomerized to the chemically more stable 8-ethyl-chlorin by further illumination. As a by-product, zinc 8-vinyl-7,8-cis-bacteriochlorin was slightly formed by photoinduced 1,2-hydrogenation of zinc 8-vinyl-chlorin. 相似文献
44.
Kenji Sugimoto Kosuke Tamura Chihiro Tohda Naoki Toyooka Hideo Nemoto Yuji Matsuya 《Bioorganic & medicinal chemistry》2013,21(15):4459-4471
As an extended study on development of anti-Alzheimer’s disease agent, we newly synthesized various dihydrofuran-fused perhydrophenanthrenes via o-quinodimethane chemistry. This study revealed that the introduction of carbon side-chain on 8-position or removal of the acetal moiety on 3-position arose a cytotoxicity on rat cortical neurons. On the other hand, the ethereal or thio-ethereal substituent on 8-position enhanced the elongation effect on Aβ-damaged neurons. The necessity of the cyano group on 10b position was also proved in this structure–activity-relationship study. 相似文献
45.
Masao Ohashi Takuji Oyama Endy Widya Putranto Tsuyoshi Waku Hiromi Nobusada Ken Kataoka Kenji Matsuno Masakazu Yashiro Kosuke Morikawa Nam-ho Huh Hiroyuki Miyachi 《Bioorganic & medicinal chemistry》2013,21(8):2319-2332
In the continuing study directed toward the development of peroxisome proliferator-activated receptor gamma (hPPARγ) agonist, we attempted to improve the water solubility of our previously developed hPPARγ-selective agonist 3, which is insufficiently soluble for practical use, by employing two strategies: introducing substituents to reduce its molecular planarity and decreasing its hydrophobicity via replacement of the adamantyl group with a heteroaromatic ring. The first approach proved ineffective, but the second was productive. Here, we report the design and synthesis of a series of α-benzyl phenylpropanoic acid-type hPPARγ partial agonists with improved aqueous solubility. Among them, we selected (R)-7j, which activates hPPARγ to the extent of about 65% of the maximum observed with a full agonist, for further evaluation. The ligand-binding mode and the reason for the partial-agonistic activity are discussed based on X-ray-determined structure of the complex of hPPARγ ligand-binding domain (LBD) and (R)-7j with previously reported ligand-LDB structures. Preliminal apoptotic effect of (R)-7j against human scirrhous gastric cancer cell line OCUM-2MD3 is also described. 相似文献
46.
Tomohide Uno Kazuki Sakamoto Yuri Isoyama Susumu Hiragaki Yuichi Uno Kengo Kanamaru Hiroshi Yamagata Michihiro Takagi Akira Mizoguchi Makio Takeda 《Histochemistry and cell biology》2013,139(2):299-308
Rab proteins are small GTPases that play essential roles in vesicle transport. In this study, we examined the expression of Rab proteins and neuropeptide hormones in the brain of the silkworm, Bombyx mori. We produced antibodies against B. mori Rab1 and Rab14 in rabbits. Immunoblotting of samples of brain tissue from B. mori revealed a single band for each antibody. Rab1 and Rab14 immunohistochemical labeling in the brain of B. mori was restricted to neurons of the pars intercerebralis and dorsolateral protocerebrum. Rab1, Rab7 and Rab14 co-localized with bombyxin. Rab1 and Rab7 co-localized with eclosion hormone. Rab1 co-localized with prothoracicotropic hormone. These results suggest that Rab1, Rab7 and Rab14 may be involved in neuropeptide transport in the brain of B. mori. This is the first report on the specificity of Rab proteins for the secretion of different neuropeptides in insects. 相似文献
47.
48.
Toshio Muto Ryozo Sugawara Katsuhiko Mizoguchi 《Bioscience, biotechnology, and biochemistry》2013,77(5):624-627
A house fly attracting substance, referred to as D3 in the preceeding paper,1) was identified with 1,3-diolein.Among the related compounds, 1- and 2-monoolein and α,ω-glycol monooleate with the formula: CH3(CH2)7CH=CH(CH2)7COO(CH2)nOH (n≦6), were found to have activities ten times that of 1,3-diolein. 相似文献
49.
Haruya Takahashi Kosuke Kamakari Hideyuki Suzuki Shinsuke Mohri Tsuyoshi Goto Nobuyuki Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(10):1761-1764
We previously reported that the two peroxisome proliferator-activated receptor-α agonists, 9- and 13-oxo-octadecadienoic acids (oxo-ODAs), were found in the tomato fruit. However, their localization remains unknown. Herein, we showed that oxo-ODAs localize primarily in the fruit peel and their amount increases after the homogenization of the tomato fruit. 相似文献
50.
Yohei Miyanoiri Mitsuhiro Takeda Kosuke Okuma Akira M. Ono Tsutomu Terauchi Masatsune Kainosho 《Journal of biomolecular NMR》2013,57(3):237-249
The 1H–13C HMQC signals of the 13CH3 moieties of Ile, Leu, and Val residues, in an otherwise deuterated background, exhibit narrow line-widths, and thus are useful for investigating the structures and dynamics of larger proteins. This approach, named methyl TROSY, is economical as compared to laborious methods using chemically synthesized site- and stereo-specifically isotope-labeled amino acids, such as stereo-array isotope labeling amino acids, since moderately priced, commercially available isotope-labeled α-keto acid precursors can be used to prepare the necessary protein samples. The Ile δ1-methyls can be selectively labeled, using isotope-labeled α-ketobutyrates as precursors. However, it is still difficult to prepare a residue-selectively Leu and Val labeled protein, since these residues share a common biosynthetic intermediate, α-ketoisovalerate. Another hindering drawback in using the α-ketoisovalerate precursor is the lack of stereo-selectivity for Leu and Val methyls. Here we present a differential labeling method for Leu and Val residues, using four kinds of stereo-specifically 13CH3-labeled [U–2H;15N]-leucine and -valine, which can be efficiently incorporated into a protein using Escherichia coli cellular expression. The method allows the differential labeling of Leu and Val residues with any combination of stereo-specifically isotope-labeled prochiral methyls. Since relatively small amounts of labeled leucine and valine are required to prepare the NMR samples; i.e., 2 and 10 mg/100 mL of culture for leucine and valine, respectively, with sufficient isotope incorporation efficiency, this approach will be a good alternative to the precursor methods. The feasibility of the method is demonstrated for 82 kDa malate synthase G. 相似文献