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1.
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   

2.
广东土牛膝为菊科泽兰属植物华泽兰(Eupatorium chinense)的干燥根。从其甲醇提取物中共分离得到11个化合物,其中eupatorinA(1)为一新化合物,经波谱学方法鉴定为(threo)-3-O-acetyl-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenoxy]propyl-β-D-glucopy-ranoside。已知化合物分别鉴定为(threo)-3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-2-[4-(3-hydroxy-1-(E)-propenyl)-2,6-dimethoxyphenox-y]-propyl-β-D-glucopyranoside(2),ardisiacrispinA(3),ardisiac-rispinB(4),euparone(5),3-(2,3-dihydroxy-isopen-tyl)-4-hydroxyacetophenone(6),12,13-di-hydroxy-euparin(7),gymnastone(8),N-(2′-hydroxy-tetracosanosyl)-2-amino-1,3,4-trihydroxy-octa-dec-8-(E)-ene(9),stigmasterol(10)和stigmasterol-3-O-β-D-glucopyranoside(11)。化合物2-4为首次从菊科植物,5-8为首次从泽兰属植物中分离得到。  相似文献   

3.
Although the enzyme-linked immunosorbent assay (ELISA) is well established for quantitating epitopes on inactivated virions used as vaccines, it is less suited for detecting potential overlaps between the epitopes recognized by different antibodies raised against the virions. We used fluorescent correlation spectroscopy (FCS) to detect the potential overlaps between 3 monoclonal antibodies (mAbs 4B7-1H8-2E10, 1E3-3G4, 4H8-3A12-2D3) selected for their ability to specifically recognize poliovirus type 3. Competition of the Alexa488-labeled mAbs with non-labeled mAbs revealed that mAbs 4B7-1H8-2E10 and 4H8-3A12-2D3 compete strongly for their binding sites on the virions, suggesting an important overlap of their epitopes. This was confirmed by the cryo-electron microscopy (cryo EM) structure of the poliovirus type 3 complexed with the corresponding antigen-binding fragments (Fabs) of the mAbs, which revealed that Fabs 4B7-1H8-2E10 and 4H8-3A12-2D3 epitopes share common amino acids. In contrast, a less efficient competition between mAb 1E3-3G4 and mAb 4H8-3A12-2D3 was observed by FCS, and there was no competition between mAbs 1E3-3G4 and 4B7-1H8-2E10. The Fab 1E3-3G4 epitope was found by cryoEM to be close to but distinct from the epitopes of both Fabs 4H8-3A12-2D3 and 4B7-1H8-2E10. Therefore, the FCS data additionally suggest that mAbs 4H8-3A12-2D3 and 4B7-1H8-2E10 bind in a different orientation to their epitopes, so that only the former sterically clashes with the mAb 1E3-3G4 bound to its epitope. Our results demonstrate that FCS can be a highly sensitive and useful tool for assessing the potential overlap of mAbs on viral particles.  相似文献   

4.
Five compounds including furanocoumarin monomers (bergamottin, 6', 7'-dihydroxybergamottin (DHB)), furanocoumarin dimers (4-??6-hydroxy-71-?(1-hydroxy-1-methyl)ethyl-4-methyl-6-(7-oxo-7H- furo?3,2-g1benzopyran-4-yl)-4-hexenyl]oxy]-3,7-dimethyl- 2-octenyl]oxy]-7H-furo[3,2-g]?1benzopyran-7-one (GF-I-1) and 4-??6-hydroxy-7??4-methyl-1-(1-methylethenyl)-6-(7-oxo-7H-furo?3, 2-g1benzopyran-4-yl)-4-hexenyl?xy-3, 7-dimethyl-2-octenyl?xy-7H-furo?3,2-g1benzopyran-7-one (GF-I-4)), and a sesquiterpene nootkatone have been isolated from grapefruit juice and screened for their inhibitory effects toward human cytochrome P450 (P450) forms using selective substrate probes. Addition of ethyl acetate extract of grapefruit juice into an incubation mixture resulted in decreased activities of CYP3A4, CYP1A2, CYP2C9, and CYP2D6. All four furanocoumarins clearly inhibited CYP3A4-catalyzed nifedipine oxidation in concentration- and time-dependent manners, suggesting that these compounds are mechanism-based inhibitors of CYP3A4. Of the furanocoumarins investigated, furanocoumarin dimers, GF-I-1 and GF-I-4, were the most potent inhibitors of CYP3A4. Inhibitor concentration required for half-maximal rate of inactivation (K(I)) values for bergamottin, DHB, GF-I-1, and GF-I-4 were calculated, respectively, as 40.00, 5. 56, 0.31, and 0.13 microM, whereas similar values were observed on their inactivation rate constant at infinite concentration of inhibitor (k(inact), 0.05-0.08 min(-1)). Apparent selectivity toward CYP3A4 does occur with the furanocoumarin dimers. In contrast, bergamottin showed rather stronger inhibitory effect on CYP1A2, CYP2C9, CYP2C19, and CYP2D6 than on CYP3A4. DHB inhibited CYP3A4 and CYP1A2 activities at nearly equivalent potencies. Among P450 forms investigated, CYP2E1 was the least sensitive to the inhibitory effect of furanocoumarin components. A sesquiterpene nootkatone has no significant effect on P450 activities investigated except for CYP2A6 and CYP2C19 (K(i) = 0.8 and 0.5 microM, respectively).  相似文献   

5.
The dual serotonin (5-HT) re-uptake inhibitor and 5-HT(1A) receptor agonist vilazodone was found to increase central serotonin levels in rat brain. In the course of structural modifications of vilazodone 3-[4-[4-(2-oxo-2H-1-benzopyran-6-yl)-1-piperazinyl]-butyl]-1H-indole-5-carbonitrile 8i and its fluorine analogue 6-[4-[4-(5-fluor-3-indolyl)-butyl]-1-piperazinyl]-2H-1-benzopyran-2-one have been identified. These unsubstituted chromenones are equally potent at the 5-HT(1A) receptor and 5-HT transporter. The implementation of nitrogen functionalities in position 3 of the chromenones resulted in compounds acting as agonists at the 5-HT(1A) receptor and as 5-HT re-uptake inhibitors like vilazodone. Ex vivo 5-HT re-uptake inhibition and in vitro 5-HT agonism were determined in the PCA- and GTPgammaS-assay, respectively. The potential of these chromenones to increase central 5-HT levels was measured in microdialysis studies and especially the derivatives 3-[4-[4-(3-amino-2-oxo-2H-chromen-6-yl)-piperazin-1-yl]-butyl]-1H-indole-5-carbonitrile 8f, ethyl (6-[4-[4-(5-cyano-1H-indol-3-yl)-butyl]-piperazin-1-yl]-2-oxo-2H-chromen-3-yl)-carbamate 8h and N-(6-[4-[4-(5-cyano-1H-indol-3-yl)-butyl]-piperazin-1-yl]-2-oxo-2H-chromen-3-yl)-acetamide 8k give rise to rapid development of increased serotonin levels in rat brain cortex, lasting longer than 3h.  相似文献   

6.
The effects of nine methylsulfonyl (MeSO(2)) metabolites of tetra-, penta- and hexachlorinated biphenyls (tetra-, penta- and hexaCBs; 20 micromol/kg once daily for 4 days) on the hepatic microsomal UDP-glucuronosyltransferase (UDP-GT) were investigated in male Sprague-Dawley rats. Each of the seven 3-MeSO(2)-PCBs, 3-MeSO(2)-2, 2',4',5-tetraCB (3-MeSO(2)-CB49), 3-MeSO(2)-2,3',4',5-tetraCB (3-MeSO(2)-CB70), 3-MeSO(2)-2,2',3',4',5-pentaCB (3-MeSO(2)-CB87), 3-MeSO(2)-2,2',4',5,5'-pentaCB (3-MeSO(2)-CB101), 3-MeSO(2)-2,2',3', 4',5,6-hexaCB (3-MeSO(2)-CB132), 3-MeSO(2)-2,2',3',4',5,5'-hexaCB (3-MeSO(2)-CB141), 3-MeSO(2)-2,2',4',5,5',6-hexaCB (3-MeSO(2)-CB149) and 4-MeSO(2)-2,2',4',5,5'-pentaCB (4-MeSO(2)-CB101) increased the activities of UDP-GT toward chloramphenicol, 4-nitrophenol and 4-methylumbelliferone. 4-MeSO(2)-2,2',4',5,5',6-hexaCB (4-MeSO(2)-CB149) increased the activity of UDP-GT toward chloramphenicol (UGT2B1) but not toward 4-nitrophenol (UGT1A6) and 4-methylumbelliferone (UGT1A6). The activity of UDP-GT toward thyroxine (T(4)) significantly increased after the administration of each of the seven 3-MeSO(2)-PCBs and 4-MeSO(2)-CB101. Significant correlation was found between the activity of UDP-GT toward T(4) and serum total T(4) concentration after the administration of each of the MeSO(2) derivatives except 4-MeSO(2)-CB149. In conclusion, seven 3-MeSO(2)-PCBs and 4-MeSO(2)-CB101 induce both UGT2B1 and UGT1A6, and 4-MeSO(2)-CB149 induces UGT 2B1. The results from the present study indicate that increase in the hepatic T(4) glucuronidation after the administration of the seven 3-MeSO(2)-PCBs and 4-MeSO(2)-CB101 possibly because of the induction of both UGT1A1 and UGT1A6 caused the reduction of serum T(4) levels.  相似文献   

7.
It was previously shown that alkaline borohydride treatment of human midcycle cervical mucin releases a heterogeneous population of reduced neutral, sialylated, and sulfated oligosaccharides (Yurewicz, E. C., and Moghissi, K. S. (1981) J. Biol. Chem. 256, 11895-11905). Three major neutral oligosaccharides were isolated with approximate compositions of Fuc:Gal:GlcNAc:N-acetylgalactosaminitol (GalNAcol) = 0:2:1:1 (A1), 1:2:1:1 (A2), and 2:2:1:1 (A3). They comprised roughly 21%, 13%, and 8% of human cervical mucin oligosaccharide chains, respectively. In the present report, each was analyzed by periodate oxidation, methylation, and sequential degradation with glycosidases. A1 was shown to contain more than one component, but structural analyses clearly demonstrated the presence of one predominant (75%) tetrasaccharide. The proposed structure, Gal beta 1-4GlcNAc beta 1-6(Gal beta 1-3)GalNAcol, has previously been found in human gastric, submaxillary, and ovarian cyst mucins in their carbohydrate-to-protein linkage regions. beta-Galactosidase from Aspergillus niger selectively cleaved the Gal beta 1-4GlcNAc linkage in the intact tetrasaccharide. Enzymatic hydrolysis of the Gal beta 1-3GalNAcol linkage required prior removal of the Gal beta 1-4GlcNAc beta 1-unit attached to 0-6 of GalNAcol. The data for A2 indicated a mixture of two oligosaccharides, Gal beta 1-4,3(Fuc alpha 1-3,4)GlcNAc beta 1-6(Gal beta 1-3)GalNacol and Fuc alpha 1-2Gal beta 1-4GlcNac beta 1-6(Gal beta 1-3)-GalNacol, in an approximate molar ratio of 3 to 4:1, respectively. Two structures are consistent with the data obtained for A3: Fuc alpha 1-2Gal beta 1-4,3(Fuc alpha 1-3,4)GlcNAc beta 1-6(Gal beta 1-3)GalNAcol and/or Gal beta 1-4,3(Fuc alpha 1-3,4)GlcNac beta 1-6(Fuc alpha 1-2Gal beta 1-3)GalNacol. The results indicate that A1 represents the "core" tetrasaccharide of the larger human cervical mucin oligosaccharides A2 and A3.  相似文献   

8.
9.
Two new alleles (A1 B*3 and A1 B*4) of human plasma alpha 1 B-glycoprotein (alpha 1 B) were reported. alpha 1 B phenotyping was done by using either a simple method of two-dimensional (2-D) agarose gel-horizontal polyacrylamide gel electrophoresis (PAGE) followed by protein staining or by one-dimensional horizontal PAGE and immunoblotting. Seven different alpha 1 B phenotypes (1-1, 1-2, 1-3, 1-4, 2-2, 2-3 and 3-3) were observed; phenotypes 1-3 and 1-4 were differentiated from each other only by the 2-D method. The respective frequencies Af A1 B*1, A1 B*2, A1 B*3 and A1 B*4 alleles in the studied populations were estimated as follows: American Blacks (New York) 0.732, 0.204, 0.064, 0; American Whites (New York) 0.947, 0.053; Czechs (M?lník) 0.964, 0.034, 0, 0.002; Slovaks (Bratislava and Trencin) 0.977, 0.023, 0, 0. The population of American Blacks showed a much higher degree of alpha 1 B polymorphism (polymorphism information content = 0.37) than the Caucasian populations that have been studied.  相似文献   

10.
A series of new 4-amino-3-[3-[4-(2-methoxy or nitro phenyl)-1-piperazinyl] propyl]thio]-5-(substitutedphenyl)[1,2,4]triazoles 11a-t was synthesized in order to obtain compounds with high affinity and selectivity for 5-HT(1A) receptor over the alpha(1)-adrenoceptor. A series of isomeric 4-amino-2-[3-[4-(2-methoxy or nitro phenyl)-1-piperazinyl]propyl]-5-(substitutedphenyl)-2,4-dihydro-3H[1,2,4]triazole-3-thiones 12a-r was also isolated and characterized. New compounds were tested to evaluate their affinity for 5-HT(1A) receptor and alpha(1)-adrenoceptor in radioligand binding experiments. As a general trend, triazoles 11a-t showed a preferential affinity for the 5-HT(1A) receptor whereas isomeric 2,4-dihydro-3H[1,2,4]triazole-3-thiones 12a-r preferentially bind to the alpha(1)-adrenoceptor site. Several molecules showed affinities in the nanomolar range and 4-amino-3-[3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl]thio]-5-(4-propyloxy-phenyl)[1,2,4]triazole (11o) was the most selective derivative for the 5-HT(1A) receptor (K(i) alpha(1)/K(i) 5-HT(1A)=55). The decrease in 5-HT(1A) receptor selectivity in 3-[3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl]thio]-5-(substitutedphenyl)[1,2,4] triazole 14a-b, lacking in the amino group in 4-position of the triazole ring, in comparison with their analogues in the series 11a-t, suggest that the amino function represents a critical structural feature in determining 5-HT(1A) receptor selectivity in this class of compounds.  相似文献   

11.
A series of new 1,3-dipropyl-8-(1-heteroarylmethyl-1H-pyrazol-4-yl)-xanthine derivatives as A(2B)-AdoR antagonists have been synthesized and evaluated for their binding affinities for the A(2B), A(1), A(2A), and A(3)-AdoRs. 8-(1-((3-phenyl-1,2,4-oxadiazol-5-yl)methyl)-1H-pyrazol-4-yl)-1,3-dipropyl-1H-purine-2,6(3H,7H)-dione (4) displayed high affinity (K(i)=1 nM) and selectivity for the A(2B)-AdoR versus A(1), A(2A), and A(3)-AdoRs (A(1)/A(2B), A(2A)/A(2B), and A(3)/A(2B) selectivity ratios of 370, 1100, and 480, respectively). The synthesis and SAR of this novel class of compounds are presented herein.  相似文献   

12.
A new class of selective alpha(1) adrenoceptor antagonists derived from the antipsychotic drug sertindole is described. The most potent and selective compound 1-(2-(4-[5-aminomethyl-1-(4-fluorophenyl)-1H-indol-3-yl]-1-piperidinyl)ethyl)-2-imidazolidinone (11) binds with 0.50 nM affinity for alpha(1) adrenergic receptors and with more than 44 times lower affinity for dopamine D(2),D(3), D(4) and serotonin 5-HT(1A), 5-HT(1B), 5-HT(2A) and 5-HT(2C) receptors. The molecular features providing high affinity for adrenergic alpha(1) receptors and high selectivity towards dopamine D(2) and serotonin 5-HT(2A) and 5-HT(2C) receptors are discussed.  相似文献   

13.
In our efforts to identify agents that would specifically inhibit ALDH3A1, we had previously studied extensively the effect of an N(1)-alkyl, an N(1)-methoxy, and several N(1)-hydroxy-substituted ester derivatives of chlorpropamide on the catalytic activities of ALDH3A1s derived from human normal stomach mucosa (nALDH3A1) and human tumor cells (tALDH3A1), and of two recombinant aldehyde dehydrogenases, viz. human rALDH1A1 and rALDH2. The N(1)-methoxy analogue of chlorpropamide, viz. 4-chloro-N-methoxy-N-[(propylamino)carbonyl]benzenesulfonamide (API-2), was found to be a relatively selective and potent inhibitor of tALDH3A1-catalyzed oxidation as compared to its ability to inhibit nALDH3A-catalyzed oxidation, but even more potently inhibited ALDH2-catalyzed oxidation, whereas an ester analogue, viz. (acetyloxy)[(4-chlorophenyl)sulfonyl]carbamic acid 1,1-dimethylethyl ester (NPI-2), selectively inhibited tALDH3A1-catalyzed oxidation as compared to its ability to inhibit nALDH3A1-, ALDH1A1- and ALDH2-catalyzed oxidations, and this inhibition was apparently irreversible. Three additional chlorpropamide analogues, viz. 4-chloro-N,O-bis(ethoxycarbonyl)-N-hydroxybenzenesulfonamide (NPI-4), N,O-bis(carbomethoxy)methanesulfohydroxamic acid (NPI-5), and 2-[(ethoxycarbonyl)oxy]-1,2-benzisothiazol-3(2H)-one 1,1-dioxide (NPI-6), were evaluated in the present investigation. Quantified were NAD-linked oxidation of benzaldehyde catalyzed by nALDH3A1 and tALDH3A1, and NAD-linked oxidation of acetaldehyde catalyzed by rALDH1A1 and rALDH2, all at 37 degrees C and pH 8.1, and in the presence and absence of inhibitor. NPI-4, NPI-5 and NPI-6 were not substrates for the oxidative reactions catalyzed by any of the ALDHs studied. Oxidative reactions catalyzed by the ALDH3A1s, rALDH1A1 and rALDH2 were each inhibited by NPI-4 and NPI-5. NPI-6 was a poor inhibitor of nALDH3A1- and tALDH3A1-catalyzed oxidations, but was a relatively potent inhibitor of rALDH1A1- and rALDH2-catalyzed oxidations. In all cases, inhibition of ALDH-catalyzed oxidation was directly related to the product of inhibitor concentration and preincubation (enzyme+inhibitor) time. As judged by the product values (microMxmin) required to effect 50% inhibition (IC(50)): (1) nALDH3A1 and tALDH3A1 were essentially equisensitive to inhibition by NPI-4 and NPI-5, and both enzymes were poorly inhibited by NPI-6; (2) rALDH1A1 was, relative to the ALDH3A1s, slightly more sensitive to inhibition by NPI-4 and NPI-5, and far more sensitive to inhibition by NPI-6; and (3) rALDH1A1 was, relative to rALDH2, essentially equisensitive to inhibition by NPI-5, whereas, it was slightly more sensitive to inhibition by NPI-4 and NPI-6.  相似文献   

14.
Cheng L  Chen Q  Du Y 《Carbohydrate research》2007,342(11):1496-1501
A tetrasaccharide, dodecanyl 4-O-acetyl-alpha-l-rhamnopyranosyl-(1-->3)-2,4-di-O-acetyl-alpha-l-rhamnopyranosyl-(1-->3)-4-O-acetyl-alpha-l-rhamnopyranosyl-(1-->4)-alpha-l-rhamnopyranoside (cleistetroside-2), was synthesized via '2+2' convergent strategy. Sequential regioselective 3-O-glycosylation of isopropyl 1-thio-alpha-l-rhamnopyranoside (4) with 4-O-acetyl-2,3-O-isopropylidene-alpha-l-rhamnopyranosyl trichloroacetimidate (8), and isopropyl 4-O-acetyl-2,3-O-isopropylidene-alpha-l-rhamnopyranosyl-(1-->3)-2,4-di-O-acetyl-alpha-l-1-thio-rhamnopyranoside (10) with dodecanyl 4-O-acetyl-alpha-l-rhamnopyranosyl-(1-->4)-2,3-O-isopropylidene-alpha-l-rhamnopyranoside (12), greatly facilitate the target availability.  相似文献   

15.
A facile approach towards the synthesis of 4-nitrophenyl O-alpha-L-fucopyranosyl-(1----3)-2-acetamido-2-deoxy-beta-D-glucopyra nos ide, 2-nitrophenyl O-alpha-L-fucopyranosyl-(1----3)-O-(2-acetamido-2-deoxy-beta-D-glucop yra nosyl)- (1----6)-2-acetamido-2-deoxy-alpha-D-galactopyranoside, 4-nitrophenyl O-alpha-L-fucopyranosyl-(1----3)-O-(2-acetamido-2-deoxy-beta-D-glucop yra nosyl)- (1----6)-alpha-D-mannopyranoside, and 4-nitrophenyl O-alpha-L-fucopyranosyl-(1----3)-O-(2-acetamido-2-deoxy-beta-D-glucop yra nosyl)-(1----6)-beta-D-galactopyranoside has been accomplished through the development and use of methyl 3,4-O-isopropylidene-2-O-(4-methoxybenzyl)-1-thio-beta-L-fucopyranoside as the glycosyl donor.  相似文献   

16.
A series of nine 3-arylamino-1-chloropropan-2-ols 2a-2i were synthesized and their anti-fungal activity against pathogenic strains of Aspergillus fumigatus, Aspergillus flavus, Aspergillus niger and Candida albicans, and antibacterial activity against four pathogenic bacterial strains of Salmonella typhi, Pseudomonas aeruginosa, Streptococcus pneumonae and Staphylococcus aureus were evaluated using different assay systems. 1-Chloro-3-(4'-chlorophenylamino)-propan-2-ol was found to be the most active anti-fungal compound against three pathogenic strains under study, i.e., A. fumigatus, A. flavus and A. niger; the compound showed more than 90% inhibition of growth of A. fumigatus at a concentration of 5.85 microg/ml in disc diffusion assay. Interestingly, 1-chloro-3-(4'-chlorophenylamino)-propan-2-ol did not show any toxicity up to a concentration of 4000 microg/ml. Although 1-chloro-3-(4'-chlorophenylamino)-propan-2-ol was about 8 times less active than the standard compound amphotericin B, its toxicity was many more fold less than the toxicity of amphotericin B. Further, 1-chloro-3-(2',6'-dichlorophenylamino)-propan-2-ol and 1-chloro-3-(3',5'-dichlorophenylamino)-propan-2-ol were found to be the most active compounds against C. albicans. In the anti-microbial assay, 1-chloro-3-(2',4'-dichlorophenylamino)-propan-2-ol and 1-chloro-3-(3',5'-dichlorophenylamino)-propan-2-ol were found to be the most active compounds against Salmonella typhi and 1-chloro-3-(3',4'-dichlorophenylamino)-propan-2-ol was found to be the most active compound against P. aeruginosa. Although, the activities of 1-chloro-3-(2',4'-dichlorophenylamino)-propan-2-ol and 1-chloro-3-(3',5'-dichlorophenylamino)-propan-2-ol are about half the activity of the standard anti-bacterial compound tetracycline, these compounds also were many fold less toxic than the standard drug.  相似文献   

17.
A novel type of N-linked glycopeptides representing a major part of the glycans in human small intestinal epithelial cells from blood group A and O individuals were isolated by gel filtrations and affinity chromatography on concanavalin A-Sepharose and Bandeiraea simplicifolia lectin I-Sepharose. Sugar composition, methylation analysis, 1H NMR spectroscopy of the underivatized glycopeptides and FAB-mass spectrometry and electron impact-mass spectrometry of the permethylated glycopeptides indicated a tri- and tetra-antennary structure containing an intersecting N-acetylglucosamine and an alpha (1----6)-linked fucose residue in the core unit for the majority of the glycans. In contrast to most glycopeptides of other sources, the intestinal glycopeptides were devoid of sialic acid, but contained 6-7 residues of fucose. The outer branches contained the following structures: Fuc alpha 1-2Gal beta 1-3GleNAc beta 1- (H type 1) Fuc alpha 1-2Gal beta 1-4GleNAc beta 1- (H type 2) Gal beta 1-4 (Fuc alpha 1-3)GlcNAc beta 1- (X) Fuc alpha 1-2Gal beta 1-4(Fuc alpha 1-3)GleNAc beta 1- (Y) GalNAc alpha 1-3(Fuc alpha 1-2)Gal beta 1-3GleNAc beta 1- (A type 1) GalNAc alpha 1-3(Fuc alpha 1-2)Gal beta 1-4GleNAc beta 1- (monofucosyl A type 2) GalNAc alpha 1-3(Fuc alpha 1-2)Gal beta 1-4 (Fuc alpha 1-3)GlcNAc beta 1- (trifucosyl A type 2) The blood group determinant structures were mainly of type 2, whereas glycolipids from the same cells contained mainly type 1 determinants. The polyfucosylated glycans represent a novel type of blood group active glycopeptides. The unique properties of the small intestinal glycopeptides as compared with glycopeptides of other tissue sources may be correlated with the specialized functional properties of the small intestinal epithelial cells.  相似文献   

18.
In our efforts to identify agents that would specifically inhibit ALDH3A1, we had previously studied extensively the effect of an N(1)-alkyl, an N(1)-methoxy, and several N(1)-hydroxy-substituted ester derivatives of chlorpropamide on the catalytic activities of ALDH3A1s derived from human normal stomach mucosa (nALDH3A1) and human tumor cells (tALDH3A1), and of two recombinant aldehyde dehydrogenases, viz. human rALDH1A1 and rALDH2. The N(1)-methoxy analogue of chlorpropamide, viz. 4-chloro-N-methoxy-N-[(propylamino)carbonyl]benzenesulfonamide (API-2), was found to be a relatively selective and potent inhibitor of tALDH3A1-catalyzed oxidation as compared to its ability to inhibit nALDH3A-catalyzed oxidation, but even more potently inhibited ALDH2-catalyzed oxidation, whereas an ester analogue, viz. (acetyloxy)[(4-chlorophenyl)sulfonyl]carbamic acid 1,1-dimethylethyl ester (NPI-2), selectively inhibited tALDH3A1-catalyzed oxidation as compared to its ability to inhibit nALDH3A1-, ALDH1A1- and ALDH2-catalyzed oxidations, and this inhibition was apparently irreversible. Three additional chlorpropamide analogues, viz. 4-chloro-N,O-bis(ethoxycarbonyl)-N-hydroxybenzenesulfonamide (NPI-4), N,O-bis(carbomethoxy)methanesulfohydroxamic acid (NPI-5), and 2-[(ethoxycarbonyl)oxy]-1,2-benzisothiazol-3(2H)-one 1,1-dioxide (NPI-6), were evaluated in the present investigation. Quantified were NAD-linked oxidation of benzaldehyde catalyzed by nALDH3A1 and tALDH3A1, and NAD-linked oxidation of acetaldehyde catalyzed by rALDH1A1 and rALDH2, all at 37 degrees C and pH 8.1, and in the presence and absence of inhibitor. NPI-4, NPI-5 and NPI-6 were not substrates for the oxidative reactions catalyzed by any of the ALDHs studied. Oxidative reactions catalyzed by the ALDH3A1s, rALDH1A1 and rALDH2 were each inhibited by NPI-4 and NPI-5. NPI-6 was a poor inhibitor of nALDH3A1- and tALDH3A1-catalyzed oxidations, but was a relatively potent inhibitor of rALDH1A1- and rALDH2-catalyzed oxidations. In all cases, inhibition of ALDH-catalyzed oxidation was directly related to the product of inhibitor concentration and preincubation (enzyme+inhibitor) time. As judged by the product values (microM x min) required to effect 50% inhibition (IC(50)): (1) nALDH3A1 and tALDH3A1 were essentially equisensitive to inhibition by NPI-4 and NPI-5, and both enzymes were poorly inhibited by NPI-6; (2) rALDH1A1 was, relative to the ALDH3A1s, slightly more sensitive to inhibition by NPI-4 and NPI-5, and far more sensitive to inhibition by NPI-6; and (3) rALDH1A1 was, relative to rALDH2, essentially equisensitive to inhibition by NPI-5, whereas, it was slightly more sensitive to inhibition by NPI-4 and NPI-6.  相似文献   

19.
A new lignan 1-hydroxy-2-(4-hydroxy-3-methoxyphenyl)-6-(3-acetyl-4-hydroxy-5-methoxyphenyl)-3,7-dioxabicyclo[3.3.0]octane, the secoiridoid 2H-pyran-4-acetic acid,3-hydroxymethyl-2,3-dihydro-5-(methoxycarbonyl)-2-methyl-, methyl ester, the phenylglycoside 4-[beta-D-xylopyranosyl-(1-->6)]-beta-D-glucopyranosyl-1,4-dihydroxy-2-methoxybenzene and the lactone 3-[1-(hydroxymethyl)-1-propenyl] delta-glutarolactone were isolated and identified on the basis of spectroscopic data including two-dimensional NMR, as components of olive oil mill waste-waters. The known aromatic compounds catechol, 4-hydroxybenzoic acid, protocatechuic acid, vanillic acid, 4-hydroxy-3,5-dimethoxybenzoic acid, 4-hydroxyphenylacetic acid, 3,4-dihydroxyphenylacetic acid, tyrosol, hydroxytyrosol, 2-(4-hydroxy-3-methoxy)phenylethanol, 2-(3,4-dihydroxy)phenyl-1,2-ethandiol, p-coumaric acid, caffeic acid, ferulic acid, sinapic acid, 1-O-[2-(3,4-dihydroxy)phenylethyl]-(3,4-dihydroxy)phenyl-1,2-ethandiol, 1-O-[2-(4-hydroxy)phenylethyl]-(3,4-dihydroxy)phenyl-1,2-ethandiol, D(+)-erythro-1-(4-hydroxy-3-methoxy)-phenyl-1,2,3-propantriol, p-hydroxyphenethyl-beta-D-glucopyranoside,2(3,4-dihydroxyphenyl)ethanol 3beta-D-glucopyranoside, and 2(3,4-dihydroxyphenyl)ethanol 4beta-D-glucopyranoside were also confirmed as constituents of the waste-waters.  相似文献   

20.
Two series of arylpiperazinyl-alkyl quinoline-, isoquinoline-, naphthalene-sulfonamides with flexible (13-26) and semi-rigid (33-36) alkylene spacer were synthesized and evaluated for 5-HT(1A), 5-HT(2A), 5-HT(6), 5-HT(7) and selected compounds for D(2), D(3), D(4) receptors. The compounds with a mixed 5-HT and D receptors profile 16 (N-{4-[4-(3-chlorophenyl)-piperazin-1-yl]-butyl}-3-quinolinesulfonamide) and 36 (4-(4-{2-[4-(4-chloro-phenyl)-piperazin-1-yl]-ethyl}-piperidine-1-sulfonyl)-isoquinoline), displaying antagonistic activity at 5-HT(7), 5-HT(2A), D(2) postsynaptic sites, produced antidepressant-like effects in the forced swim test in mice and showed significant anxiolytic activity in the plus-maze test in rats. The lead compound 36, a multi-receptor 5-HT(2A)/5-HT(7)/D(2)/D(3)/D(4) agent, also displayed significant antipsychotic properties in the MK-801-induced hyperlocomotor activity in mice.  相似文献   

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