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1.
Structural characterizations of marsupial milk oligosaccharides have been performed in only three species: the tammar wallaby, the red kangaroo and the koala. To clarify the homology and heterogeneity of milk oligosaccharides among marsupials, 21 oligosaccharides of the milk carbohydrate fraction of the common brushtail possum were characterized in this study. Neutral and acidic oligosaccharides were separated from the carbohydrate fraction of mid-lactation milk and characterized by 1H-nuclear magnetic resonance spectroscopy and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. The structures of the 7 neutral oligosaccharides were Gal(β1-3)Gal(β1-4)Glc (3’-galactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc (3”, 3’-digalactosyllactose), Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I), Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (galactosyl lacto-N-novopentaose I), Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-3)Gal(β1-4)Glc (galactosyl lacto-N-novopentaose II). The structures of the 14 acidic oligosaccharides detected were Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Glc (sialyl 3’-galactosyllactose), Gal(β1-3)(O-3-sulfate)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I sulfate a) Gal(β1-3)[Gal(β1-4)(O-3-sulfate)GlcNAc(β1-6)]Gal(β1-4)Glc (lacto-N-novopentaose I sulfate b), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)(?3-O-sulfate)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)[Gal(β1-4)(?3-O-sulfate)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose b), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(?3-O-sulphate)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)(?3-O-sulphate)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)(?3-O-sulphate)GlcNAc(β1-6)]Gal(β1-4)Glc and Gal(β1-3)Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (galactosyl sialyl lacto-N-novopentaose b). No fucosyl oligosaccharides were detected. Galactosyl lacto-N-novopentaose II, lacto-N-novopentaose I sulfate a, lacto-N-novopentaose I sulfate b and galactosyl sialyl lacto-N-novopentaose b are novel oligosaccharides. The results are compared with those of previous studies on marsupial milk oligosaccharides.  相似文献   

2.
In the milk of marsupials, oligosaccharides usually predominate over lactose during early to mid lactation. Studies have shown that tammar wallaby milk contains a major series of neutral galactosyllactose oligosaccharides ranging in size from tri- to at least octasaccharides, as well as β(1-6) linked N-acetylglucosamine-containing oligosaccharides as a minor series. In this study, acidic oligosaccharides were purified from red kangaroo milk and characterized by (1)H-nuclear magnetic resonance spectrometry and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, to be as follows: Neu5Ac(α2-3)Gal(β1-4)Glc (3'-SL), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-4)Glc (sialyl 3'-galactosyllactose), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Neu5Ac(α2-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose a), Gal(β1-3)[Neu5Ac(α2-6)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc (sialyl lacto-N-novopentaose b), Neu5Ac(α2-3)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-3)Gal(β1-3)Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc, Gal(β1-3)(-3-O-sulfate)Gal(β1-3)Gal(β1-3)[Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc. These acidic oligosaccharides were shown to be sialylated or sulfated in the non-reducing ends to the major linear and the minor branched series of neutral oligosaccharides of tammar wallaby milk.  相似文献   

3.
Hydrochloric acid treatment of methyl 3-(4-isobutylphenyl)-3-methylglycidate and methyl 2-hydroxy-3-(4-isobutylphenyl)-3-butenoate, a rearrangement product of the former, in acetic acid gave 3-(4-isobutylphenyl)-3-methylpyruvic acid and 2-(4-isobutylphenyl)-pro-panal. The same treatment of 2-hydroxy-3-(4-isobutylphenyl)-3-butenoic acid gave 2-(4-isobutylphenyl)-propanal. Both 3-(4-isobutylphenyl)-3-methylpyruvic acid and 2-(4-iso-butylphenyl)-propanal were oxidized to 2-(4-isobutylphenyl)-propionic acid.  相似文献   

4.
Two trisaccharides, three tetrasaccharides, two pentasaccharides, one hexasaccharide, one heptasaccharide, one octasaccharide and one decasaccharide were isolated from polar bear milk samples by chloroform/methanol extraction, gel filtration, ion exchange chromatography and preparative thin-layer chromatography. The oligosaccharides were characterized by 1H-NMR as follows: the saccharides from one animal: Gal(α1-3)Gal(β1-4)Glc (α3′-galactosyllactose), Fuc(α1-2)Gal(β1-4)Glc (2′-fucosyllactose), Gal(α1-3)[Fuc(α1-2)]Gal(β1-4)Glc (B-tetrasaccharide), GalNAc(α1-3)[Fuc(α1-2)]Gal(β1-4)Glc (A-tetrasaccharide), Gal(α1-3)Gal(β1-4)GlcNAc(β1-3)Gal(β1-4)Glc, Gal(α1-3)[Fuc(α1-2)]Gal(β1-4)GlcNAc(β1-3)Gal(β1-4)Glc, Gal(α1-3)Gal(β1-4)GlcNAc(β1-3)[Gal(α1-3)Gal(β1-4)GlcNAc(β1-6)]Gal(β1-4)Glc; the saccharides from another animal: α3′-galactosyllactose, Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]Glc, A-tetrasaccharide, GalNAc(α1-3)[Fuc(α1-2)]Gal(β1-4)[Fuc(α1-3)]Glc (A-pentasaccharide), Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-3)Gal(β1-4)Glc, Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-3)Gal(β1-4)[Fuc(α1-3)]Glc (difucosylheptasaccharide) and Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-3){Gal(α1-3)Gal(β1-4)[Fuc(α1-3)]GlcNAc(β1-6)}Gal(β1-4)Glc (difucosyldecasaccharide). Lactose was present only in small amounts. Some of the milk oligosaccharides of the polar bear had α-Gal epitopes similar to some oligosaccharides in milk from the Ezo brown bear and the Japanese black bear. Some milk oligosaccharides had human blood group A antigens as well as B antigens; these were different from the oligosaccharides in Ezo brown and Japanese black bears.  相似文献   

5.
Two trisaccharides, three tetrasaccharides, two pentasaccharides, one hexasaccharide, one heptasaccharide, one octasaccharide and one decasaccharide were isolated from polar bear milk samples by chloroform/methanol extraction, gel filtration, ion exchange chromatography and preparative thin-layer chromatography. The oligosaccharides were characterized by 1H-NMR as follows: the saccharides from one animal: Gal(alpha1-3)Gal(beta1-4)Glc (alpha3'-galactosyllactose), Fuc(alpha1-2)Gal(beta1-4)Glc (2'-fucosyllactose), Gal(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)Glc (B-tetrasaccharide), GalNAc(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)Glc (A-tetrasaccharide), Gal(alpha1-3)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Glc, Gal(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Gl c, Gal(alpha1-3)Gal(beta1-4)GlcNAc(beta1-3)[Gal(alpha1-3)Gal(beta1-4)Glc NAc(beta1-6)]Gal(beta1-4)Glc; the saccharides from another animal: alpha3'-galactosyllactose, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc, A-tetrasaccharide, GalNAc(alpha1-3)[Fuc(alpha1-2)]Gal(beta1-4)[Fuc(alpha1-3)]Glc (A-pentasaccharide), Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Gl c, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)[F uc(alpha1-3)]Glc (difucosylheptasaccharide) and Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)?Gal(alpha1-3) Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)?Gal(beta1-4)Glc (difucosyldecasaccharide). Lactose was present only in small amounts. Some of the milk oligosaccharides of the polar bear had alpha-Gal epitopes similar to some oligosaccharides in milk from the Ezo brown bear and the Japanese black bear. Some milk oligosaccharides had human blood group A antigens as well as B antigens; these were different from the oligosaccharides in Ezo brown and Japanese black bears.  相似文献   

6.
Synthesis of egonol derivatives, 5-(3'-chloropropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 1, 5-(3'-bromopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 2, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propanal 3, 5-(3'-iodopropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 4, 5-[3-(3'-bromopropyloxy) propyl]-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 5, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylmethanoate 6, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propyloleate 7, 5-[3'-hydroxypropyl]-6-bromo-7-methoxy-2-(3',4'-methylenedioxyphenyl)benzofuran 8, 4-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]butanenitrile 9, 3-[2-(1,3-benzodioxol-5-yl)-7-methoxy-1-benzofuran-5-yl]propylbenzoate 10, 5-[3'-hydroxypropyl]-7-methoxy-3-nitro-2-(3',4'-methylenedioxyphenyl)benzofuran 11 and their antibacterial activity against Staphylococcus aureus, Bacillus subtilis, Candida albicans and Escherichia coli are reported. The starting material egonol 5-[3'-(hydroxy)propyl]-7-methoxy-2-(3', 4'methylenedioxyphenyl)benzofuran was isolated from seeds of Styrax officinalis L. The structural elucidication of these compounds (1-11) was established using 1D ((1)H, (13)C), 2D NMR (HMBC, HMQC, COSY) and LCMS spectroscopic data. While egonol and some synthesised new compounds show similar antibacterial activity and MIC values against S. aureus, B. subtilis, C. albicans and E. coli, other new derivatives show different activity against S. aureus, B. subtilis, C. albicans and E. coli.  相似文献   

7.
Ma J  Jin X  Yang L  Liu ZL 《Phytochemistry》2004,65(8):1137-1143
Seven new diarylheptanoids, i.e., (3S,5S)-3,5-diacetoxy-1,7-bis(4-hydroxy-3-methoxyphenyl)heptane, (3R,5S)-3-acetoxy-5-hydroxy-1,7-bis(4-hydroxy-3-methoxyphenyl)heptane, (3R,5S)-3,5-dihydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-7-(4-hydroxy-3-methoxyphenyl)heptane, (5S)-5-acetoxy-1,7-bis(4-hydroxy-3-methoxyphenyl)heptan-3-one, 5-hydroxy-1-(3,4-dihydroxy-5-methoxyphenyl)-7-(4-hydroxy-3-methoxyphenyl)heptan-3-one, 5-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-7-(3,4-dihydroxy-5-methoxy-phenyl)heptan-3-one and 1,5-epoxy-3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-7-(4-hydroxy-3-methoxyphenyl)heptane were isolated from the rhizomes of Chinese ginger (Zingiber officinale Roscoe), along with 25 known compounds, i.e., 8 diarylheptanoids, 14 gingerol analogs, a diterpene and 2 steroids. Their structures were elucidated by spectroscopic and chemical methods.  相似文献   

8.
The oligosaccharides present in the milk of an African elephant (Loxodonta africana africana), collected 4 days post partum, were separated by size exclusion-, anion exchange- and high-performance liquid chromatography (HPLC) before characterisation by (1)H NMR spectroscopy. Neutral and acidic oligosaccharides were identified. Neutral oligosaccharides characterised were isoglobotriose, Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc, Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc, Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc and a novel oligosaccharide that has not been reported in the milk or colostrum of any other mammal: Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc. Acidic oligosaccharides that are also found in the milk of Asian elephant were Neu5Ac(alpha2-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-6)Gal(beta1-4)Glc, Neu5Ac(alpha2-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc and Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3){Gal(alpha1-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)}Gal(beta1-4)Glc, while Neu5Gc(alpha2-3)Gal(beta1-4)Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)[Fuc(alpha1-3)]Glc, Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3)[Gal(beta1-4)GlcNAc(beta1-6)]Gal(beta1-4)Glc and Neu5Ac(alpha2-6)Gal(beta1-4)GlcNAc(beta1-3){Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-6)}Gal(beta1-4)Glc have not been found in Asian elephant milk. The oligosaccharides characterised contained both alpha(2-3)- and alpha(2-6)-linked Neu5Ac residues. They also contain only the type II chain, as found in most non-human, eutherian mammals.  相似文献   

9.
Benzofurans and another constituent from seeds of Styrax officinalis   总被引:2,自引:0,他引:2  
Akgul YY  Anil H 《Phytochemistry》2003,63(8):939-943
The benzofuran constituents of the seeds of Styrax officinalis were investigated. From the hexane extract, two new constituents named 5-(3"benzoyloxypropyl)-7-methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran (5) and 4-[3"-(1c-methylbutanoyloxy)propyl]-2-methoxy-(3',4'-methylenedioxyphenyl)-1a, 5b-dihydrobenzo-[3,4]-cyclobutaoxirene (6) were isolated together with four known compounds, 5-[3"-(1c-methylbutanoyloxy)propyl]-7-methoxy-2-(3',4'-dimethoxyphenyl)-benzofuran (4), 5-[3"-(1c-methylbutanoyloxy)propyl]-7- methoxy-2-(3',4'-methylenedioxyphenyl)-benzofuran (3), 5-(3"-acetoxypropyl)-7-methoxy2-(3',4'-methylenedioxphenyl)-benzofuran (2) and 5-(3"-hydroxypropyl)-7-methoxy-2-(3',4'-met hylenedioxyphenyl)-benzofuran (1). Although the compounds 1, 2, and 3 have been isolated previously from the seeds of Styrax obassia, this is the first record of their isolation from seeds of Styrax officinalis. The structures of the isolated compounds were established by 1D- and 2D-NMR (HMBC, HMQC, COSY), FABMS and high-resolution ESI FTMS.  相似文献   

10.
Stereochemical aspects of the formation of double bonds in abscisic acid   总被引:2,自引:1,他引:1  
The stereochemistry of the hydrogen elimination that occurs during the formation of the Delta(4)- and Delta(2)'-double bonds of abscisic acid has been determined from the (14)C/(3)H ratios in abscisic acid biosynthesized by avocado fruit from [2-(14)C,(2R)-2-(3)H(1)]-, [2-(14)C,(2S)-2-(3)H(1)]- and [2-(14)C,(5S)-5-(3)H(1)]-mevalonate. Setting the (14)C/(3)H ratio at 3:3 for [2-(14)C,(2R)-2-(3)H(1)]mevalonate, the corresponding ratio in derived methyl abscisate was 3:2.28; the analogous ratio for methyl abscisate from [2-(14)C,(2S)-2-(3)H(1)]mevalonate was 3:1.63. Removal of the 3'-hydrogen atom of abscisic acid by base-catalysed exchange altered the ratios to 3:1.55 and 3:1.44 respectively. It was concluded that this 3'-hydrogen atom is derived from the pro-2R-hydrogen atom of mevalonate. Removal of the 4-hydrogen atom from methyl abscisate by formation of a derivative, a lactone, lacking this hydrogen atom changed the ratio to 3:1.04 for material derived from [2-(14)C,(2R)-2-(3)H(1)]-mevalonate and to 3:1.05 for [2-(14)C,(2S)-2-(3)H(1)]mevalonate, showing that this hydrogen atom also is derived from the pro-2R-hydrogen atom of mevalonate. These ratios of the lactones are consistent with their retaining one (3)H atom at the 6'-methyl position of abscisic acid from the [(2R)-2-(3)H(1)]- and [(2S)-2-(3)H(1)]-mevalonate. The presence of some label at positions 3' and 4 when [(2S)-2-(3)H(1)]mevalonate was the precursor is attributed to the action of isopentenyl pyrophosphate isomerase. The hydrogen atom at C-5 of abscisic acid is derived from the pro-5S-hydrogen atom of mevalonate.  相似文献   

11.
The biotransformation of raspberry ketone and zingerone were individually investigated using cultured cells of Phytolacca americana. In addition to (2S)-4-(4-hydroxyphenyl)-2-butanol (2%), (2S)-4-(3,4-dihydroxyphenyl)-2-butanol (5%), 4-[4-(beta-d-glucopyranosyloxy)phenyl]-2-butanone (19%), 4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (23%), and (2S)-4-(4-hydroxyphenyl)but-2-yl-beta-d-glucopyranoside (20%), two biotransformation products, i.e., 2-hydroxy-4-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (12%) and 2-hydroxy-5-[(3S)-3-hydroxybutyl]phenyl-beta-d-glucopyranoside (11%), were isolated from suspension cells after incubation with raspberry ketone for three days. On the other hand, two compounds, i.e., (2S)-4-(4-hydroxy-3-methoxyphenyl)but-2-yl-beta-d-glucopyranoside (17%) and (2S)-2-(beta-d-glucopyranosyloxy)-4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]butane (16%), together with (2S)-4-(4-hydroxy-3-methoxyphenyl)-2-butanol (15%), 4-[4-(beta-d-glucopyranosyloxy)-3-methoxyphenyl]-2-butanone (21%), and 4-[(3S)-3-hydroxybutyl]-2-methoxyphenyl-beta-d-glucopyranoside (24%) were obtained upon addition of zingerone. Cultured cells of P. americana can reduce, and regioselectively hydroxylate and glucosylate, these food ingredients to their beta-glycosides.  相似文献   

12.
Seven glutathione-S-transferase (GST) isozymes were purified from liver cytosol of intact male Wistar rats: 1-1(A), 1-1(B), 1-2, 2-2, 3-3, 3-4, 4-4. Treatment of rats with butylated hydroxytoluene (BHT) led to the induction of isozymes GST 1-1(A), 1-1(B) (2-fold), 3-3 (3.5-fold) as well as to the appearance of two new isozymes--1-3 and 4-4(A). Phenobarbital (PB) induced isozymes GST 1-1(A), 1-1(B) (2-fold) and 3-3 (1.5-fold). BHT and PB caused an increase in the specific activity of isozymes 1-1(A), 1-1(B), 3-3, 3-4 towards 1-chloro-2.4-dinitrobenzene and 1.2-dichloro-4-nitrobenzene. 3-Methylcholanthrene (MC) induced isozymes 1-2 (1.5-fold), 2-2 (2-fold) and 4-4 (3-fold). A conclusion was drawn that BHT and PB induced the GST subunits 1 and 3, whereas MC--subunits 2 and 4.  相似文献   

13.
As a result of screening of microorganisms, Mucor ambiguus IFO 6742 was found to reduce methyl 2-chloro-3-(4-methoxyphenyl)-3-oxopropionate (2) to give methyl (2S,3R)-2-chloro-3-hydroxy-3-(4-methoxyphenyl)propionate [(2S,3R)-3] in good yield with high enantioselectivity. The resulting (2S, 3R)-3 was converted into methyl (2S,3R)-3-(4-methoxyphenyl)glycidate [(2S,3R)-4] by treatment with sodium methoxide. On the other hand, its enantiomer, (2R,3S)-4 was obtained by the Mitsunobu esterification of (2S,3R)-3 and subsequent treatment with sodium methoxide. Also (2R,3S)-4 was obtained by the treatment of (2RS,3S)-3, which was obtained from 2 by Trichoderma viride OUT 4642, with sodium methoxide.  相似文献   

14.
Two trisaccharides, two tetrasaccharides, one penta-, one hexa-, two hepta-, one deca- and two undeca-saccharides were isolated from several Japanese black bear milk samples by chloroform/methanol extraction, gel filtration and preparative thin-layer chromatography. The oligosaccharides were characterized by 1H-NMR as follows: Gal(alpha 1-3)Gal(beta 1-4)Glc (alpha 3'-galactosyllactose), Fuc(alpha 1-2)Gal(beta 1-4)Glc (2'-fucosyllactose), Gal(alpha 1-3)(Fuc(alpha 1-2))Gal(beta 1-4)Glc (B-tetrasaccharide), Gal(alpha 1-3)Gal(beta 1-4)(Fuc(alpha 1-3))Glc, Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]Glc (B-pentasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4)Glc (monofucosylhexasaccharide), Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4)Glc (difucosylheptasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]Glc (difucosylheptasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)[Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-6)]Gal(beta 1-4)Glc (difucosyldecasaccharide), Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)[Gal(alpha 1-3) Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-6)]Gal(beta 1-4)Glc (trifucosylundecasaccharide), Gal(alpha 1-3)Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-3)[Gal(alpha 1-3)[Fuc(alpha 1-2)]Gal(beta 1-4)[Fuc(alpha 1-3)]GlcNAc(beta 1-6)]Gal(beta 1-4)Glc (trifucosylundecasaccharide). Lactose was present only in trace amounts. B-pentasaccharide was a dominant saccharide in early lactation milk, while alpha 3'-galactosyllactose was dominant in milk, later. The milk oligosaccharides of the Japanese black bear were compared with those of the Ezo brown bear.  相似文献   

15.
Nine compounds, 3-hydroxy-4,5-dimethoxyphenyl-beta-D-glucopyranoside (1), beta-D-fructfuranosyl-alpha-D-(6-vanilloyl)-glucopyranoside (2), beta-D-fructfuranosyl-alpha-D-(6-syringyl)-glucopyranoside (3), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2-methoxyphenoxy]propyl-beta-D-glucopyranoside (4), 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy] propyl-beta-D-glucopyranoside (5), dehydrodiconiferyl alcohol-9'-beta-D-glucopyranoside (6), 4-[ethane-2-[3-(4-hydroxy-3-methoxyphenyl)-2-propen]oxy]-2,6-dimethoxyphenyl-beta-D-glucopyranoside (7), 4-[ethane-2-[3-(4-hydroxy-3-methoxyphenyl)-2-propen]oxy]-2-methoxyphenyl-beta-D-glucopyranoside (8), and 3-hydroxy-1-(4-hydroxy-3,5-dimethoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy]propyl-beta-D-glucopyranoside (9), were isolated from Kokuto non-centrifuged cane sugar. Their structures were elucidated by spectroscopic evidence, mainly based on the NMR technique. Among them, seven new glycosides were identified. The 2-deoxyribose oxidation method was used to measure their antioxidative activity. All of these compounds showed antioxidative activities.  相似文献   

16.
A series of N1-nicotinoyl-3- (4-hydroxy-3-methyl phenyl)-5-(substituted phenyl)-2-pyrazolines were synthesized by the reaction between isoniazid (INH) and chalcones and were tested for their in vitro anti-viral activity. Among the compounds, the electron withdrawing group substituted analogues 5-(4-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4, 5-dihydro-1H-1- pyrazolyl-4-pyridylmethanone (4b), 5-(2-chlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro-1H-1-pyrazolyl-4-pyri- dylmethanone (4i), 5-(4-fluorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro- 1H-1-pyrazolyl-4-pyridylmethanone (4h) and 5-(2,6-dichlorophenyl)-3-(4-hydroxy-3-methylphenyl)-4,5-dihydro- 1H-1-pyrazolyl-4-pyridyl methanone (4j) were the most promising and the halogeno function appeared to be essential for antiviral activity.  相似文献   

17.
We have reconstituted the platelet glycoprotein (GP) Ib-IX-mediated activation of the integrin alpha(IIb)beta(3) in a recombinant DNA expression model, and show that 14-3-3 is important in GPIb-IX signaling. CHO cells expressing alpha(IIb)beta(3) adhere poorly to vWF. Cells expressing GPIb-IX adhere to vWF in the presence of botrocetin but spread poorly. Cells coexpressing integrin alpha(IIb)beta(3) and GPIb-IX adhere and spread on vWF, which is inhibited by RGDS peptides and antibodies against alpha(IIb)beta(3). vWF binding to GPIb-IX also activates soluble fibrinogen binding to alpha(IIb)beta(3) indicating that GPIb-IX mediates a cellular signal leading to alpha(IIb)beta(3) activation. Deletion of the 14-3-3-binding site in GPIbalpha inhibited GPIb-IX-mediated fibrinogen binding to alpha(IIb)beta(3) and cell spreading on vWF. Thus, 14-3-3 binding to GPIb-IX is important in GPIb-IX signaling. Expression of a dominant negative 14-3-3 mutant inhibited cell spreading on vWF, suggesting an important role for 14-3-3. Deleting both the 14-3-3 and filamin-binding sites of GPIbalpha induced an endogenous integrin-dependent cell spreading on vWF without requiring alpha(IIb)beta(3), but inhibited vWF-induced fibrinogen binding to alpha(IIb)beta(3). Thus, while different activation mechanisms may be responsible for vWF interaction with different integrins, GPIb-IX-mediated activation of alpha(IIb)beta(3) requires 14-3-3 interaction with GPIbalpha.  相似文献   

18.
Bestrophin-1 (Best1) is a Cl(-) channel that is linked to various retinopathies in both humans and dogs. Dysfunction of the Best1 Cl(-) channel has been proposed to cause retinopathy because of altered Cl(-) transport across the retinal pigment epithelium (RPE). In addition to Cl(-), many Cl(-) channels also transport HCO3(-). Because HCO3(-) is physiologically important in pH regulation and in fluid and ion transport across the RPE, we measured the permeability and conductance of bestrophins to HCO3(-) relative to Cl(-). Four human bestrophin homologs (hBest1, hBest2, hBest3, and hBest4) and mouse Best2 (mBest2) were expressed in HEK cells, and the relative HCO3(-) permeability (P HCO3/PCl) and conductance (G HCO3/GCl) were determined. P HCO3/PCl was calculated from the change in reversal potential (Erev) produced by replacing extracellular Cl(-) with HCO3(-). hBest1 was highly permeable to HCO3(-) (P HCO3)/PCl = approximately 0.44). hBest2, hBest4, and mBest2 had an even higher relative HCO3(-) permeability (P HCO3/PCl = 0.6-0.7). All four bestrophins had HCO3(-) conductances that were nearly the same as Cl(-) (G HCO3/GCl = 0.9-1.1). Extracellular Na+ did not affect the permeation of hBest1 to HCO3(-). At physiological HCO3(-) concentration, HCO3(-) was also highly conductive. The hBest1 disease-causing mutations Y85H, R92C, and W93C abolished both Cl(-) and HCO3(-) currents equally. The V78C mutation changed P HCO3/PCl and G HCO3/GCl of mBest2 channels. These results raise the possibility that disease-causing mutations in hBest1 produce disease by altering HCO3(-) homeostasis as well as Cl(-) transport in the retina.  相似文献   

19.
Enzymes from Salvia officinalis and Tanacetum vulgare leaf epidermis catalyze the conversion of the acyclic precursor geranyl pyrophosphate to the cyclic monoterpenes (+)- and (-)-bornyl pyrophosphate, respectively. The antipodal cyclizations are considered to proceed by the initial isomerization of the substrate to the respective bound tertiary allylic intermediates (-)-(3R)- and (+)-(3S)-linalyl pyrophosphate. [(3R)-8,9-14C,(3RS)-1E-3H] Linalyl pyrophosphate (3H:14C = 5.22) was tested as a substrate with the cyclases from both sources to determine the configuration of the cyclizing intermediate. This substrate yielded (-)-bornyl pyrophosphate with 3H:14C ratio greater than 31, indicating specific utilization of (+)-(3S)-linalyl pyrophosphate as predicted. With the (+)-bornyl pyrophosphate cyclase, the 3H:14C ratio of the product was about 4.16, indicating a preference for the (-)-(3R)-enantiomer, but the ability also to utilize (+)-(3S)-linalyl pyrophosphate. (3R)- and (3S)-[1Z-3H]Linalyl pyrophosphate were separately compared to the achiral precursors [1-3H] geranyl pyrophosphate and [1-3H]neryl pyrophosphate (cis-isomer) as substrates for the cyclizations. All functional precursors afforded optically pure (-)-(1S,4S)-bornyl pyrophosphate with the T. vulgare-derived cyclase (as determined by chromatographic separation of diastereomeric ketals of the derived ketone camphor), and (+)-(3S)-linalyl pyrophosphate was the preferred substrate. With the (+)-bornyl pyrophosphate cyclase from S. officinalis, geranyl, neryl, and (-)-(3R)-linalyl pyrophosphates gave the expected (+)-(1R,4R)-stereoisomer as the sole product, and (-)-(3R)-linalyl pyrophosphate was the preferred substrate. However, (3S)-linalyl pyrophosphate yielded (-)-(1S,4S)-bornyl pyrophosphate, albeit at lower rates, indicating the ability of this enzyme to catalyze the anomalous enantiomeric cyclization.  相似文献   

20.
The reaction of triphenylphosphinegold(I) chloride in ethanol in a 1:1 molar ratio with the 3-(aryl)-2-sulfanylpropenoic acids H(2)xspa [x: p=3-phenyl-, Clp=3-(2-chlorophenyl)-, -o-mp=3-(2-methoxyphenyl)-, -p-mp=3-(4-methoxyphenyl)-, -o-hp=3-(2-hydroxyphenyl)-, -p-hp=3-(4-hydroxyphenyl)-, diBr-o-hp=3-(3,5-dibromo-2-hydroxyphenyl)-, f=3-(2-furyl)-, t=3-(2-thienyl)-, -o-py=3-(2-pyridyl)-; spa=2-sulfanylpropenoato] gave compounds of the type [Au(PPh(3))(Hxspa)], which were isolated and characterized as solids by elemental analysis, IR spectroscopy and FAB mass spectrometry and in solution by (1)H, (13)C and (31)P NMR spectroscopy. The structures of the complexes [Au(PPh(3))(HClpspa)], [Au(PPh(3))(H-o-mpspa)] and [Au(PPh(3))(H-p-mpspa)].2/3C(3)H(6)O were determined by X-ray diffractometry. Hydrogen bonding was found along with Au-S and Au-P bonds in all cases and weak pi-pi stacking was found in the H-p-mpspa derivative. The in vitro antitumour activities against the HeLa-229, A2780 and A2780cis cell lines were determined for all complexes.  相似文献   

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