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1.
Amides in a CH2Cl2 extract from the fruits of Piper retrofractum were detected by HPLC/APCI-MS. Seven new unsaturated amides, together with six known ones, were isolated, and their structures were determined to be N-isobutyl-2E,4E,12Z-octadecatrienamide (1), N-isobutyl-2E,4E,14Z-eicosatrienamide (2), 1-(octadeca-2E,4E,12Z-trienoyl)piperidine (3), 1-(eicosa-2E,4E,14Z-trienoyl)piperidine (4), 1-(octadeca-2E,4E-dienoyl)piperidine (5), 1-(eicosa-2E,4E-dienoyl)piperidine (6), and 1-(eicosa-2E,14Z-dienoyl)piperidine (7) on the basis of chemical and spectroscopic evidence.  相似文献   

2.
The fate of O,O-dipropyl S-[2-(2′-methyl-1-piperidinyl)-2-oxo-ethyl] phosphorodithioate (C 19 490, piperophos) was followed in greenhouse-grown rice after application of 1.6 kg/ha 14C-labeled C 19 490 into the paddy water. At maturity the shoots contained 2.5 ppm and the hulled grains 0.16 ppm 14C-C 19 490 equivalents. Small amounts of unchanged C 19 490 were found in the shoots but none in the grains.

The main metabolites found were:- 2-(2′-methyl-1-piperidiny])-2-oxo-ethane sulfonic acid, 2-(2?-methyl-1?-piperidinyl)-2-oxo-ethanoic acid and a fraction of polar unknown substances. O,O-Dipropyl S-[2-(2?-methyl-1 -piperidinyl)-2-oxo-ethyl] phosphorothioate, 2-(2?-methyl-1?-piperidinyl)- 1-methyl-sulfinyl-2-oxo-ethane, 2-(2?-methyl-1?-piperidinyl)-1-methyl-sulfonyl-2-oxo- ethane, 2-methyl-piperidine and CO2 were found in smaller amounts.  相似文献   

3.
Nine fructo-oligosaccharides, synthesized in vitro from sucrose by an enzyme preparation from asparagus roots, were isolated and their structures were elucidated to be 1F (1-β-fructofuranosyl)n sucrose [n = 1 (1-kestose), 2 (nystose) and 3], 6G (1-β-fructofuranosyl)n sucrose [n=1 (neokestose), 2 and 3] and 1F (1-β-fructofuranosyl)m-6G (1-β-fructofuranosyl)n sucrose [m=1, n=1; m=2, n =1; and m =1, n=2]. These saccharides are all known to occur naturally in asparagus roots, but 6G (1-β-fructofuranosyl)3 sucrose and 1F (1-β-fructofuranosyl)m-6G-(1-β-fructofuranosyl)n sucrose (m=1, n =1; and m=1, n=2) were the first saccharides enzymatically synthesized in vitro. Also three types of fructosyltransferases were presumed to be involved in the biosynthesis of these oligosaccharides in asparagus roots.  相似文献   

4.
(2R*,4S*,6S*,αS*)- and (2R,4R,6RS)-Streptovitacin-C2 (STV-C2) (1a and 1b) were synthesized by an aldol condensation of (2R*,4S*)- or (2R,4R)-2,4-dimethyl-2-trimethylsiloxy-1-cyclohexanone (15a or 15b) with 4-(2-oxoethyl)-2,6-piperidinedione (16), which was followed by desilylation of the products. The stereochemistry of the synthesized STV-C2 isomers (1a and 1b) was elucidated by NMR. STV-C2 isomers (1a and 1b) did not show strong antimicrobial activity against Saccharomyces cerevisiae and Pyricularia oryzae.  相似文献   

5.
6.
《Biomarkers》2013,18(5):441-446
Context: Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) play divergent roles in myocardial ischemia and reperfusion injury.

Objective: To investigate serum Ang-1 and Ang-2 levels in ST-segment elevation myocardial infarction (STEMI) patients treated with primary percutaneous coronary intervention (PCI).

Methods: Serum Ang-1 and Ang-2 were measured in 85 STEMI patients in the first week after PCI.

Results: Ang-1, Ang-2 and Ang-2/Ang-1 ratio (Ang-2/1) were all increased at admission, and had dynamic changes after PCI. Ang-2 and Ang-2/1 at admission and 2 h after PCI were positively correlated with peak cardiac troponin T levels.

Conclusion: The extent of myocardial damage may be linked to circulating Ang-2 and Ang-2/1.  相似文献   

7.
Detached mungbean (Vigna radiata L.Wilczek) leaves were inoculated with a conidial suspension of a local isolate (TI-1) of the powdery mildew pathogen (Erysiphe polygoni DC) under controlled environment conditions. Based on the latent period and severity of the infection, a rating scale of 0–5 was used to classify the host pathogen interactions. Reactions 0, 1 and 2 were considered resistant and referred to as R0, R1 and R2 while 3, 4 and 5 were classified as susceptible (S). RUM lines (resistant to powdery mildew) and their derivatives are crossed with several susceptible (reaction types 3–5) genotypes and the inheritance of the resistance was studied in the F1, F2 and F3 generations. The results showed that powdery mildew resistance in mungbean is governed by two dominant genes designated as Pm-1 and Pm-2. When both Pm-1 and Pm-2 were present, an R0 reaction was observed after inoculation with TI-1. The resistant reaction was R1 when only Pm-1 was present and R2 in the presence of Pm-2. In the absence of both Pm-1 and Pm-2, susceptible reactions 3, 4 and 5 were observed.  相似文献   

8.
Sheep x hamster cell hybrids containing sheep metacentric Chromosome (Chr) 2 were produced by fusing blood leukocytes from normal sheep with hamster auxotrophic Ade F-minus mutants. Cell clones that were isocitrate dehydrogenase 1 (IDH1) positive were cytogenetically characterized, confirming that they contained sheep Chr 2. The following loci were newly assigned by Southern hybridization to sheep Chr 2: lipoprotein lipase (LPL), glycoprotein-4-beta galactosyltransferase 2 (GGTB2), neurofilament light polypeptide (68 kDa; NEFL), surfactant-associated protein 2 (SFTP2), lymphocyte-specific protein tyrosine kinase (LCK), and nebulin (NEB). These new assignments and the in situ localization of gelsolin (GSN) to sheep Chr 2pter-p24 are consistent with the predicted homology of cattle Chr 8 (U18) with sheep Chr 2p, and of cattle Chr 2 (U17) with sheep 2q. In addition, the assignment by cell hybrid analysis of loci previously mapped to Chr 2 in sheep, viz., cholinergic receptor, nicotinic, delta polypeptide (CHRND), collagen type III alpha 1 (COL3A1), fibronectin 1 (FN1), isocitrate dehydrogenase (IDH1), and villin 1 (VIL1), confirmed the localization of sheep syntenic group U11 to this chromosome. By nutritional selection and complementation of the hamster auxotrophic Ade F mutation, the multifunctional enzyme locus phosphoribosylaminoimidazolecarboxamide formyltransferase (AICAR transformylase)/IMP cyclohydrolase (inosinicase) (provisionally given the symbol PRACFT) has also been newly assigned to sheep Chr 2. This report significantly extends the number of loci physically mapped to sheep Chr 2 and confirms its close homology with cattle Chrs 2 and 8.  相似文献   

9.
In the current study, 18 salt-tolerant bacteria were isolated from salt-affected soil of Erzurum, Turkey. Forty-five bacterial isolates were identified and characterized by conventional and molecular techniques. These 45 sequenced isolates were identified as 16 different genus including Bacillus (19 isolates), Staphylococcus (3 isolates), Halobacillus (4 isolates), Zhihengliuella (2 isolates), Oceanobacillus (2 isolates), Halomonas (1 isolate), Nesterenkonia (2 isolates), Promicromonospora (2 isolates), Jeotgalibacillus (2 isolates), Planococcus (2 isolates), Virgibacillus (1 isolate), Terribacillus (1 isolate), Thalassobacillus (1 isolate), Marinibacillus (1 isolate), Gracilibacillus (1 isolate) and Microbacterium (1 isolate). According to the results obtained, investigated bacterial strains have high salt tolerance and significant enzyme activities that can improve soil nutrient cycling and soil fertility. The current article provides the evaluation and diversity of the potential halotolerant and halophilic bacterial strains in salt-affected soils of Erzurum, Turkey.  相似文献   

10.
Acidic oligosaccharides were separated by dialysis, ion-exchange, preparative paper and gel chromatography from caprine colostrum. Four sialyl trisaccharides were characterized by 1H-NMR spectrometry as follows: α-N-acetylneuraminyl-(2,6)-β-d-galactopyranosyl-(1,4)-2-N-acetamido-2-deoxy-d-glucopyranose (Neu5Ac α 2-6Gal β 1-4GlcNAc), α-N-acetylneuraminyl-(2,3)-β-d-galactopyranosyl-(1,4)-d-glucopyranose (Neu5Ac α 2-3Gal β-1-4Glc), α-N-acetylneuraminyl-(2,6)-β-d-galactopyranosyl-(1,4)-d-glucopyranose (Neu5Ac α 2-6Gal β 1-4Glc) and α-N-glycolylneuraminyl-(2,6)-β-d-galactopyranosyl-(1,4)-d-glucopyranose (Neu5Gc α 2-6Gal β 1-4Glc).  相似文献   

11.
12.
13.
Summary Two extracellular -fructofuranosidases (E-1 andE-2) fromAureobasidium sp. ATCC 20524, producing 1-kestose (1F--fructofuranosyl-sucrose) from sucrose, were purified to homogeneity. Molecular weights of the enzymes were estimated to be about 304000 (E-1) and 315000 (E-2) Da by gel filtration. The enzymes contained 33% (w/w) (E-1) and 27% (w/w) (E-2) carbohydrate. TheK m values for sucrose ofE-1 andE-2 andE-2 were 0.34 and 0.28 M, respectively. were 0.34 and 0.28 M, respectively. The enzymatic profiles of these enzymes were almost identical to intracellular enzymesP-1 andP-2 except for the differences in carbohydrate content andK m values ofE-2 andP-2.  相似文献   

14.
15.
The thymidine mimics isocarbostyril nucleosides and difluorophenyl nucleosides were tested as deoxynucleoside kinase substrates using recombinant human cytosolic thymidine kinase (TK1) and deoxycytidine kinase (dCK), and mitochondrial thymidine kinase (TK2) and deoxyguanosine kinase (dGK). The isocarbostyril nucleoside compound 1‐(2‐deoxy‐β‐D‐ribofuranosyl)‐isocarbostyril (EN1) was a poor substrate with all the enzymes. The phosphorylation rates of EN1 with TK1 and TK2 were < 1% relative to Thd, where as the phosphorylation rates for EN1 were 1.4% and 1.1% with dCK and dGK relative to dCyd and dGuo, respectively. The analogue 1‐(2‐deoxy‐β‐D‐ribofuranosyl)‐7‐iodoisocarbostyril (EN2) showed poor relative‐phosphorylation efficiencies (k cat /K m ) with both TK1 and dGK, but not with TK2. The k cat /K m value for EN2 with TK2 was 12.6% relative to that for Thd. Of the difluorophenyl nucleosides, 5‐(1′‐(2′‐deoxy‐β‐D‐ribofuranosyl))‐2,4‐difluorotoluene (JW1) and 1‐(1′‐(2′‐deoxy‐β‐D‐ribofuranosyl))‐2,4‐difluoro‐5‐iodobenzene (JW2) were substrates for TK1 with phosphorylation efficiencies of about 5% relative to that for Thd. Both analogues were considerably more efficient substrates for TK2, with k cat /K m values of 45% relative to that for Thd. 2,5‐Difluoro‐4‐[1‐(2‐deoxy‐β‐L‐ribofuranosyl)]‐aniline (JW5), a L‐nucleoside mimic, was phosphorylated up to 15% as efficiently as deoxycytidine by dCK. These data provide a possible explanation for the previously reported lack of cytotoxicity of the isocarbostyril‐ and difluorophenyl nucleosides, but potential mitochondrial effects of EN2, JW1 and JW2 should be further investigated.  相似文献   

16.
Two new pyrrolosesquiterpenes, 1 and 2 , were isolated from cultures of the soil actinomycete Streptomyces sp. Hd7–21. The structures of these compounds were established as (2Z,4E,9E)‐6,7,11‐trihydroxy‐3,7,11‐trimethyl‐1‐(1H‐pyrrol‐2‐yl)dodeca‐2,4,9‐trien‐1‐one ( 1 ) and (2Z,4E)‐5‐{3‐[(2E)‐4‐hydroxy‐4‐methylpent‐2‐en‐1‐yl]‐3‐methyloxiran‐2‐yl}‐3‐methyl‐1‐(1H‐pyrrol‐2‐yl)penta‐2,4‐dien‐1‐one ( 2 ) by extensive spectroscopic analyses including MS, and 1D‐ and 2D‐NMR data. Their cytotoxic activities against a panel of human cancer cell lines were evaluated.  相似文献   

17.
小麦PPO活性基因等位变异的区域分布研究   总被引:1,自引:0,他引:1  
为了解中国不同生态区小麦种质资源籽粒多酚氧化酶(PPO)活性基因的等位变异的差异与分布,利用小麦PPO活性基因的功能标记PPO16、PPO29与PPO18,检测了来自中国7个不同生态麦区的379份小麦种质资源的等位变异和分布差异。结果表明:(1)在2AL染色体该基因位点有2种等位变异类型:Ppo-A1a(高PPO)和Ppo-A1b(低PPO),其频率分别为51.5%和48.5%。(2)在2DL染色体该基因位点有3种等位变异类型:Ppo-D1a(低PPO)、Ppo-D1b(高PPO)和Ppo-D1ab(中间型),其频率分别为57.8%、32.5%和9.8%。(3)该基因在2AL和2DL染色体上的位点变异有6种不同类型的组合:Ppo-A1a/D1a(中间型)、Ppo-A1a/D1b(高PPO)、Ppo-A1a/Ppo-D1ab(中间型)、Ppo-A1b/D1a(低PPO)、Ppo-A1b/D1b(中间型)和Ppo-A1b/Ppo-D1ab(中间型),其中,与低PPO活性相关的基因型组合Ppo-A1b/D1a的频率为25.6%。(4)小麦PPO活性基因不同变异类型在各生态区的分布存在明显差异,基因型Ppo-A1b在北部冬麦区和西南冬麦区的比例较大,基因型Ppo-D1a在黄淮冬麦区和北部冬麦区的比例较大,基因型组合Ppo-A1b/D1a在北部冬麦区的比例较大。研究认为,结合采用分子标记辅助选择(MAS),有利于小麦籽粒外观品质的遗传改良和新品种选育。  相似文献   

18.
COM1/SAE2 is a highly conserved gene from yeast to higher eukaryotes. Its orthologs, known to cooperate with the MRX complex (Mre11/Rad50/Xrs2), are required for meiotic DNA double‐strand break (DSB) ends resection and specific mitotic DSB repair events. Here, the rice (Oryza sativa, 2n = 2x = 24) COM1/SAE2 homolog was identified through positional cloning, termed OsCOM1. Four independent mutants of OsCOM1 were isolated and characterized. In Oscom1 mutants, synaptonemal complex (SC) formation, homologous pairing and recombination were severely inhibited, whereas aberrant non‐homologous chromosome entanglements occurred constantly. Several key meiotic proteins, including ZEP1 and OsMER3, were not loaded normally onto chromosomes in Oscom1 mutants, whereas the localization of OsREC8, PAIR2 and PAIR3 seemed to be normal. Moreover, OsCOM1 was loaded normally onto meiotic chromosomes in Osrec8, zep1 and Osmer3 mutants, but could not be properly loaded in Osam1, pair2 and OsSPO11‐1RNAi plants. These results provide direct evidence for the functions of OsCOM1 in promoting homologous synapsis and recombination in rice meiosis.  相似文献   

19.
Two new lupane-triterpene glycosides named acankoreosides C and D, were isolated from the leaves of Acanthopanax koreanum. Based on spectroscopic data, the chemical structures were determined as 3-O-β- -glucopyranosyl 3α,11α-dihydroxylup-20(29)-en-28-oic acid 28-O-α- -rhamnopyranosyl-(1→4)-β- -glucopyranosyl-(1→6)-β- -glucopyranosyl ester and 3α,11α-dihydroxylup-23-al-20(29)-en-28-oic acid 28-O-α- -rhamnopyranosyl-(1→4)-β- -glucopyranosyl-(1→6)-β- -glucopyranosyl ester, respectively.  相似文献   

20.
Designed, synthesized a sequence of novel benzimidazol-1-yl-1-phenylpropanone hybrids and assessed for in vitro antimicrobial potential counter to several bacterial strains. Computational Methodology was carried out for designing of the target molecules and structures were confirmed by spectroscopic analysis. Amid the 12 integrated derivatives, (3-(2-((3-fluorobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6g ) and 3-(2-((4-fluorobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6k ) were found to acquire excellent antibacterial activity against all bacterial strains (Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, Staphylococcus aureus), whereas derivative 3-(2-((2-fluorobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6c ), was potent against Escherichia coli, Bacillus subtilis, Staphylococcus aureus and displayed moderate action against P. aeruginosa. Derivatives with NO2 substituent at 3rd and 4th position, 3-(2-((3-nitroobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6h ) and 3-(2-((4-nitroobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6 l ) respectively declared good to moderate results against all bacterial strains. Further, 3-(2-((3-chlorobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6f ) and 3-(2-((4-chlorobenzylidene)amino)-1H-benzo[d]imidazol-1-yl)-1-phenylpropan-1-one ( 6j ) were found to be more competent against both fungal strains (C. albicans, A. niger). Serial two-fold dilution method was used for the entire study and standard drugs utilized were ciprofloxacin and clotrimazole. MIC values (μg/ml) of novel synthesized analogs were reported in comparison to standard drugs for antibacterial and antifungal actions. Molecular docking studies showed that designed molecules dynamically bound with effective area of the receptor (DNA gyrase B, Clotrimazole complex of cytochrome P 45046A1) and in vitro results were in accord with in silico studies.  相似文献   

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