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31.
A benzoquinone and flavonoids from Cyperus alopecuroides   总被引:1,自引:0,他引:1  
A benzoquinone, named alopecuquinone, was isolated from the ethanol extract of the inflorescences of Cyperus alopecuroides. Its structure was primarily elucidated by spectroscopic analysis including 1H, 13C NMR, APT, HMQC, 1H-1H COSY and CIMS. The known flavonoids, vicenin 2, orientin, diosmetin, quercetin 3,3'-dimethyl ether and its 3,4'-dimethyl ether, were also isolated and characterized. The ethanol extract of the plant material showed moderate estrogenic activity using a strain of Saccharomyces cerevisiae.  相似文献   
32.
A 70-day rearing trial was done to determine the optimal frequency of feeding on growth performance (GP), feed conversion rate (FCR), cannibalism, survival rate (SR), body chemical composition and economic efficiency of the Asian sea bass. This study tested four different treatments of feeding frequencies (FF), once (T1), twice (T2), three times (T3), and four times (T4) per day. An average initial weight of Asian sea bass fry was 0.2 g (SD = ±0.12) were stocked 10 individuals per m3 (9.14 m × 1.82 m × 1.22 m, L × W × H; water depth 0.61 m) with two replicates per treatment (4 × 2 = 8). Fry were fed a mixture of larval commercial feed and shrimp with a pellet diet containing (46% CP). Initially, the feeding rate of 8% biomass per day was further adjusted according to fish biomass on a weekly basis. Results showed that, the FF significantly affected (p < 0.05) on growth indictors and survival rate (SR). Specifically fry fed three times a day (T3) had the best FBW, FL, SGR, ADWG and FCR followed by T4 and T2 while fry fed one time a day was the lowest in these parameters. Also, VSI, HSI and CF (k) significantly differed among the treatments. The fish whole body content of protein, moisture and ash did not significantly (p < 0.05) be affected by feeding frequency, but lipid content differed and both T3, T4 were the highest. It could be concluded that, increasing FF up to three times a day had a positive effect on weight gain, survival rate and feed utilization of Lates calcarifer. The second degree polynomial regression indicates that fed three times a day is optimum for best growth performance and survival for Asian sea bass.  相似文献   
33.
Different 2,4-thiazolidinedione-tethered coumarins 5a–b, 10a–n and 11a–d were synthesised and evaluated for their inhibitory action against the cancer-associated hCAs IX and XII, as well as the physiologically dominant hCAs I and II to explore their selectivity. Un-substituted phenyl-bearing coumarins 10a, 10 h, and 2-thienyl/furyl-bearing coumarins 11a–c exhibited the best hCA IX (KIs between 0.48 and 0.93 µM) and hCA XII (KIs between 0.44 and 1.1 µM) inhibitory actions. Interestingly, none of the coumarins had any inhibitory effect on the off-target hCA I and II isoforms. The sub-micromolar compounds from the biochemical assay, coumarins 10a, 10 h and 11a–c, were assessed in an in vitro antiproliferative assay, and then the most potent antiproliferative agent 11a was tested to explore its impact on the cell cycle phases and apoptosis in MCF-7 breast cancer cells to provide more insights into the anticancer activity of these compounds.  相似文献   
34.
In the current work, a new set of carbohydrazide linked benzofuran-isatin conjugates (5a–e and 7a–i) was designed and synthesised. The anticancer activity for compounds (5b–d, 7a, 7b, 7d and 7g) was measured against NCI-55 human cancer cell lines. Compound 5d was the most efficient, and thus subjected to the five-dose screen where it showed excellent broad activity against almost all tested cancer subpanels. Furthermore, all conjugates (5a–e and 7a–i) showed a good anti-proliferative activity towards colorectal cancer SW-620 and HT-29 cell lines, with an excellent inhibitory effect for compounds 5a and 5d (IC50 = 8.7 and 9.4 µM (5a), and 6.5 and 9.8 µM for (5d), respectively). Both compounds displayed selective cytotoxicity with good safety profile. In addition, both compounds provoked apoptosis in a dose dependent manner in SW-620 cells. Also, they significantly inhibited the anti-apoptotic Bcl2 protein expression and increased the cleaved PARP level that resulted in SW-620 cells apoptosis.  相似文献   
35.
o-, m-, p-Phenylenediamines having 2,3,4-trihydroxy, 3,4 dihydroxy, and 4-hydroxybenzoyl moieties were prepared and their inhibitory activities were measured against topoisomerase I and II. More hydroxy groups on two aromatic rings increased the activities. Bis(trihydroxybenzoyl)-o-phenylenediamide showed IC(50)=0.90 and 0.09 microM against topoisomerase I and II, respectively. Compounds with hydroxy groups protected by acetyl moiety still had the activities. Less hydroxy groups decreased their activities. Benzothiazole derivatives also indicated the activities.  相似文献   
36.
Hordeum vulgare, cultivated barley, and its wild relative, H. chilense, have several important traits that might be useful for wheat improvement. Here, in situ hybridization and barley expressed sequence tag (EST) markers were used to characterize and compare the chromosomes of H. chilense with those of H. vulgare. FISH with four repetitive DNA sequences, AG, AAG, 5S rDNA and 45S rDNA, was applied to the mitotic chromosomes of H. vulgare, H. chilense and available wheat-H. chilense addition and substitution lines. FISH with the AAG repeat differentiated the individual chromosomes of H. chilense and H. vulgare. The patterns of FISH signals in the two species differed greatly. The 45S rDNA signals were observed on two pairs of chromosomes in both species, while the 5S rDNA signals were observed on four pairs of chromosomes in H. vulgare and on one pair in H. chilense. The AG repeat showed FISH signals at the centromeric regions of all chromosomes of H. vulgare but none of the chromosomes of H. chilense. These results indicate that the chromosomes of the two species are highly differentiated. To study the homoeology between the two species, 209 EST markers of H. vulgare were allocated to individual chromosomes of H. chilense. One hundred and forty of the EST markers were allocated to respective chromosomes of H. chilense using the wheat-H. chilense addition and substitution lines. Twenty-six EST markers on average were allocated to each chromosome except to the chromosome 2H(ch)S, to which only 10 markers were allocated. Ninety percent of the allocated EST markers in H. chilense were placed on H. vulgare chromosomes of the same homo-eologous group, indicating that the expressed sequences of the two species were highly conserved. These EST markers would be useful for detecting chromatin introgressed from these species into the wheat genome.  相似文献   
37.
38.
Abstract

Cyclic imides containing 3-benzenesulfonamide, oxime, and β-phenylalanine derivatives were synthesised and evaluated to elucidate their in vivo anti-inflammatory and ulcerogenic activity and in vitro cytotoxic effects. Most active anti-inflammatory agents were subjected to in vitro COX-1/2 inhibition assay. 3-Benzenesulfonamides (2–4, and 9), oximes (11–13), and β-phenylalanine derivative (18) showed potential anti-inflammatory activities with 71.2–82.9% oedema inhibition relative to celecoxib and diclofenac (85.6 and 83.4%, respectively). Most active cyclic imides 4, 9, 12, 13, and 18 possessed ED50 of 35.4–45.3?mg kg?1 relative to that of celecoxib (34.1?mg kg?1). For the cytotoxic evaluation, the selected derivatives 2–6 and 8 exhibited weak positive cytotoxic effects (PCE = 2/59–5/59) at 10?μM compared to the standard drug, imatinib (PCE = 20/59). Cyclic imides bearing 3-benzenesulfonamide (2–5, and 9), acetophenone oxime (11–14, 18, and 19) exhibited high selectivity against COX-2 with SI > 55.6–333.3 relative to that for celecoxib [SI > 387.6]. β-Phenylalanine derivatives 21–24 and 28 were non-selective towards COX-1/2 isozymes as indicated by their SI of 0.46–0.68.  相似文献   
39.
Abstract

Inhibitory action of newly synthesised 4-(2-(2-substituted-thio-4-oxoquinazolin-3(4H)-yl)ethyl)benzenesulfonamides compounds 2–13 against human carbonic anhydrase (CA, EC 4.2.1.1) (hCA) isoforms I, II, IX, and XII, was evaluated. hCA I was efficiently inhibited by compounds 2–13 with inhibition constants (KIs) ranging from 57.8–740.2?nM. Compounds 2, 3, 4, and 12 showed inhibitory action against hCA II with KIs between 6.4 and 14.2?nM. CA IX exhibited significant sensitivity to inhibition by derivatives 2–13 with KI values ranging from 7.1 to 93.6?nM. Compounds 2, 3, 4, 8, 9, and 12 also exerted potent inhibitory action against hCA XII (KIs ranging from 3.1 to 20.2?nM). Molecular docking studies for the most potent compounds 2 and 3 were conducted to exhibit the binding mode towards hCA isoforms as a promising step for SAR analyses which showed similar interaction with co-crystallized ligands. As such, a subset of these mercaptoquinazolin-4(3H)-one compounds represented interesting leads for developing new efficient and selective carbonic anhydrase inhibitors (CAIs) for the management of a variety of diseases including glaucoma, epilepsy, arthritis and cancer.  相似文献   
40.
Both neemix and basil oil had an insecticidal effect against Aphis craccivora Koch when the plant was treated systematically or by contact. The tested compounds caused a significant reduction in fecundity, longevity and the natal period. In addition, neemix and basil oil had a toxic effect on the adult stage of the pest, which was more clear for basil oil than neemix, since the cumulative percent morality reached 100% in all tested concentrations after 7 days for basil treatment and after 8 days for neemix oil treatment, while the mortality did not exceed 36% for the control. The two tested oils also had an antifeedant and aphicidal effect on the nymphal stage, since they caused prolongation of the nymphal duration, high percentage of mortality and only a few young ones can be succeeded to reach to the adult stage. The correlation between the biological effects of the tested compounds and the impairment of the activity of some enzymes (acid phosphatase and alkaline phosphatase) and (aspartate aminotranferase and alanine aminotransferase) as well as protein contents had also been investigated. The results clarified a significant reduction in all the tested enzymes and were more pronounced for basil oil treatment than neemix. This explained the reduction in the reproductive potency of A. craccivora Koch. Concerning the side effect of the tested compounds on faba bean plants, the results indicated that the treatment induced promising effect on the antioxidant enzymes activity (superoxide dismutase, catalase, peroxidase and polyphenol oxidase) of the plants which were treated with basil oil and neemix.  相似文献   
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