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11.
Kanho H Yaoya S Kawahara N Nakane T Takase Y Masuda K Kuroyanagi M 《Chemical & pharmaceutical bulletin》2005,53(4):361-365
The glucosylation of some coumarin and flavone derivatives on incubation with the hairy roots of morning glory (Pharbitis nil) was previously reported. We further studied the biotransformation of benzaldehyde- and acetophenone-type derivatives. Vanillin and isovanillin were reduced to alcoholic derivatives and glucosylated at the phenolic and the alcoholic hydroxyl groups. In the case of 3,4-dihydroxybenzaldehyde, the formyl group was reduced and the 3-hydroxyl or 4-hydroxyl groups were glucosylated to give monoglucosides. The 3-hydroxyl group was predominantly glucosylated to the 4-hydroxyl group. 4-beta-D-Glucopyranosyloxy-3-methoxybenzylalcohol was obtained in low yield. In time-course experiments with vanillin, it was found that the high-level reduction of the formyl group and glucosylation of the phenolic hydroxyl group occurred, and finally 4-O-beta-D-glucopyranosylvanillylalcohol was obtained as the main product. In the case of 3,4-dimethoxybenzaldehyde, 3,4,5-trimethoxybenzaldehyde, and salicylaldehyde, the formyl groups were reduced, and then the hydroxyl groups at the benyl position were glucosylated to give alcoholic glucosides in relatively high yields. In 4-hydroxy-3-methoxyacetophenone, the 4-hydroxyl group was glucosylated and two dimerized glucosides, biphenyl and biphenylether types, were obtained in low yields. In acetophenone, 1-beta-D-glucopyranosyloxy-1-phenylethane and 2-beta-D-glucopyranosyloxyacetophenone were obtained. As mentioned above P. nil hairy roots showed various biotransformative activities including glucosylation of phenolic and benzylic hydroxyl groups, reduction of the formyl group near the benzene ring, and phenol oxidation dimerization. The glucosylation reaction was especially interesting for the production of valuable glucosides. 相似文献
12.
M. SenŌ H. Noritomi Y. Kuroyanagi K. Iwamoto G. Ebert 《Colloid and polymer science》1984,262(11):896-901
The molecular conformations of poly(N5-dihydroxyethylaminopropyl-L-glutamine) and poly(N5-dihydroxyethyl-L-glutamine) were investigated in reversed micelles of AOT as well as in aqueous solutions. Both poly(-amino acid)s assume disordered structures in pure water. The conformation of poly(N5-dihydroxyethylaminopropyl-L-glutamine) transits into-helix in the reversed micelles as the molar ratio of water to AOT (w0=[H2O]/[AOT]) becomes smaller. A similar conformational transition was also observed in aqueous solutions when a certain amount of AOT was added. Under these conditions, however, poly(N5-dihydroxyethyl-L-glutamine) did not undergo a conformational transition into-helix. 相似文献
13.
Umehara K Matsumoto M Nakamura M Miyase T Kuroyanagi M Noguchi H 《Chemical & pharmaceutical bulletin》2000,48(4):566-567
In the course of searching for differentiation inducers against leukemic cells from plants, we have recognized the differentiation inducing activities of the methanolic extract of Hydrangea Dulcis Folium. Activity guided separation of the extract was carried out using M1 cells, and seven isocoumarins were isolated as active substances. These isocoumarins showed the activities at the concentration of 100 microM and non-cytotoxic effects even at 300 microM. 相似文献
14.
The conformational transition of multichain copoly(-amino acid)s consisting of copoly(-methyl-L-glutamyl-L-lysine) as backbone molecule and poly(-benzyl-L-glutamate) as branch molecules was studied in chloroform and DCA mixtures. The helix stability of backbone molecule is strongly affected by the length of branch molecules. In the case of the multichain copolymer having short branch molecular chains, i.e.,DP
br
<10, the helix conformation of the backbone molecule is strictly affected by some interferences among the randomly coiled molecular chains. In the case of water-soluble multichain copolymer having poly(L-glutamic acid) or poly(L-lysine) as branch molecules, the transitional process from coil to helix is observed by depressing hydrostatic repulsion among the ionized side chain of branch molecules. However, such conformational transition is depressed to a considerable extent by interferences among the branch molecules.Abbreviations used (shown alphabetically)
A/I
molar ratio of NCA to initiator
- Cbz
carbobenzyloxy
- DCA
dichloroacetic acid
- DMF
N,N-dimethylformamide
-
DP
br
number-average degree of polymerization of branches of multichain copolymer
-
Fw
br
weight fraction of-benzyl-L-glutamyl residues of multichain copolymer
-
Mn
number-average molecular weight
- NCA
N-carboxy anhydride of-amino acid
- ORD
optical rotatory dispersion 相似文献
15.
16.
Kuroyanagi M Ikeda R Gao HY Muto N Otaki K Sano T Kawahara N Nakane T 《Chemical & pharmaceutical bulletin》2008,56(1):60-63
In the screening of biologically active constituents from woody plants, the methanol extract of leaves of Chamaecyparis obtusa showed potent neurite outgrowth-promoting activity in neuronal PC12 cells. The ethyl acetate-soluble fraction of the methanol extract showed potent activity and was separated by means of various chromatographic methods to give the two new compounds 1 and 2, as well as 11 known lignan and sesquiterpene derivatives. The structures of the new compounds were determined to be 9-O-acetyldihydrosesamin (1) and 9-O-(11-hydroxyeudesman-4-yl)dihydrosesamin (2), respectively, in NMR studies including 2D-NMR experiments. Of the 13 compounds, the known compound hinokinin (5) and the new compound 2 showed potent neurite outgrowth-promoting activity in PC 12 cells. 相似文献
17.
Ushijima M Komoto N Sugizono Y Mizuno I Sumihiro M Ichikawa M Hayama M Kawahara N Nakane T Shirota O Sekita S Kuroyanagi M 《Chemical & pharmaceutical bulletin》2008,56(3):308-314
In the course of the development of new designer foods using the roots of Codonopsis lanceolata, we found that hot-water extracts of C. lanceolata recovered decreased testosterone levels in the blood and accelerated the restoration of reproductive dysfunction induced by hyperthermic treatment in male mice. Thus we studied the constituents of the polar fraction of the roots of C. lanceolata and identified six new triterpene saponins, lancemasides B (2), C (3), D (4), E (5), F (6), and G (7), along with the known saponin lancemasaide A (1) and phenylpropanoid glycosides 8-10. The structures of the new compounds 2-7 were determined by means of spectral data including 2D-NMR studies and chemical reactions to be oleanan-type bisdesmoside with sugars at C-3 and C-28. Compounds 2-6 have echinocystic acid as an aglycone, and compound 7 has asterogenic acid as an aglycone. Identification of the sugars and determination of their D,L-chiralities were carried out by application of the exciton chirality method to the per-O-p-bromobenzoylmethyl sugar derived from saponins. 相似文献
18.
Gao HY Wu LJ Muto N Fuchino H Nakane T Shirota O Sano T Kuroyanagi M 《Chemical & pharmaceutical bulletin》2008,56(7):1030-1034
In the course of studies on biological active constituents from woody plants, we previously reported the isolation of many lignan derivatives as neurite outgrowth-promoting compounds from an ethyl acetate soluble fraction of Japanese Cypress (Chamaecyparis obtusa). Further chemical investigation on the residual parts of the ethyl acetate soluble fraction of a methanol extract of Japanese Cypress resulted in the isolation of four new beyerene type derivatives and a novel sesquiterpene dimer formed between cryptomeridiol and hinokiic acid. Their structures were elucidated as 18-O-(Z)-p-coumaroylbeyer-15-ene-18-ol (1), 18-O-(E)-p-coumaroylbeyer-15-ene-18-ol (2), 18-O-(E)-p-coumaroylbeyer-15-ene-11beta,18-diol (3), 18-O-(Z)-p-coumaroylbeyer-15-ene-11beta,18-diol (4) and ent-cryptomeridiol-4-yl-hinokiiate (5) by (1)H-NMR, (13)C-NMR, 2D-NMR, and HR-MS spectral analysis. 相似文献
19.
Maruyama T Sugimoto N Kuroyanagi M Kim IH Kamakura H Kawasaki T Fujita M Shimada H Yamamoto Y Tada A Yamazaki T Goda Y 《Chemical & pharmaceutical bulletin》2007,55(11):1626-1630
Isodonis Herba is used as a Japanese dietary supplement and folk medicine. The extract of the herb (Isodonis extract) is also used as a food additive whose major compound is enmein (1). Here we compared internal transcribed spacer sequences of nuclear ribosomal DNA from Isodonis Herba available on the Japanese and Chinese crude drug markets, and found that the former derived from Isodon japonicus and Isodon trichocarpus, while the latter derived from distinct species such as Isodon eriocalyx. The liquid chromatography/mass spectrometry profiles of Isodonis Herba were classified into four chemotypes (A to D) according to the ratio of the major constituents. Types B and C contained 1 and oridonin (2) as major components, respectively. An intermediate (or mixed) form of types B and C in various ratios was designed type A. Type D contained eriocalyxin B (3) as its major component. Japanese herba were types A-C, while Chinese herba were types C and D. The commercial Isodonis extract products tested were classified as type D, suggesting that they originated from Chinese Herba. Understanding the relationship between extract constituents and DNA profiles is important for the official specification of dietary supplements and food additives of plant origin. 相似文献
20.
Yoshiharu Ishikawa Norihisa Kato Shigeyuki Suematsu Tokihiro Kuroyanagi 《Nuclear Physics A》1982,380(3)
In the experiments on 74Ge(d, pγ)75Ge, a 52.5±0.1 keV γ-ray was found in 75Ge with a half-life of 216±5 ns. From the analysis of the γ-ray spectra the conversion coefficient of the 52.5 keV γ-ray was determined. Then, a new level of
is confirmed to exist at 192.5 keV. The reduced transition probabilities of the 52.5 keV transition are deduced to be (6.9+5.6 −2.1) × 10−5 for B(M1) and 31+3 −2 for B(E2) in Weisskopf units. 相似文献