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151.
Chromosome engineering,mapping, and transferring of resistance to Fusarium head blight disease from Elymus tsukushiensis into wheat 总被引:1,自引:0,他引:1
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Kumar M Rawat P Khan MF Rawat AK Srivastava AK Maurya R 《Bioorganic & medicinal chemistry letters》2011,21(8):2232-2237
16-Dehydropregnenolone undergoes a smooth annulation with propan-1-amine and aromatic aldehydes. Several amine derivatives of 16- dehydropregnenolone were synthesized and evaluated as inhibitors of DPP-IV. The structures of compounds were confirmed by 1H, 13C, NMR and mass spectral analysis. Among 17 compounds evaluated only five compounds 1, 9, 13, 15 and 16 demonstrated significant inhibition of DPP. This study suggest that introduction of appropriate substituents in the 16-dehydropregnenolone plays an important role in DPP-IV inhibitory activity. 相似文献
156.
Rao VK Chhikara BS Shirazi AN Tiwari R Parang K Kumar A 《Bioorganic & medicinal chemistry letters》2011,21(12):3511-3514
An efficient and economical method was developed for the synthesis of 3-substituted indoles by one-pot three-component coupling reaction of a substituted or unsubstituted benzaldehyde, N-methylaniline, and indole or N-methylindole using Yb(OTf)3-SiO2 as a catalyst. All the synthesized compounds were evaluated for inhibition of cell proliferation of human colon carcinoma (HT-29), human ovarian adenocarcinoma (SK-OV-3), and c-Src kinase activity. The 4-methylphenyl (4o and 4p) and 4-methoxyphenyl (4q) indole derivatives inhibited the cell proliferation of SK-OV-3 and HT-29 cells by 70-77% at a concentration of 50 μM. The unsubstituted phenyl (4d) and 3-nitrophenyl (4l) derivatives showed the inhibition of c-Src kinase with IC50 values of 50.6 and 58.3 μM, respectively. 相似文献
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Low E Kim B Francavilla C Shiau TP Turtle ED O'Mahony DJ Alvarez N Houchin A Xu P Zuck M Celeri C Anderson MB Najafi RR Jain RK 《Bioorganic & medicinal chemistry letters》2011,21(12):3682-3685
Structure stability/activity relationships (SXR) of a new class of N,N-dichloroamine compounds were explored to improve antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Candida albicans while maintaining aqueous solution stability. This study identified a new class of solution-stable and topical antimicrobial agents. These agents are sulfone-stabilized and possess either a quaternary ammonium or sulfonate appendages as a water solubilizing group. Several unique challenges were confronted in the synthesis of these novel compounds which are highlighted in the discussion. 相似文献
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In the present study, anaerobic fungi were isolated from different ruminants and non-ruminants; i.e., cattle, buffalo, sheep,
goats, wild bluebulls, elephants, deer, and zebras; and were identified as Anaeromyces, Orpinomyces, Caecomyces, Piromyces, and Neocallimastix sp., based on their morphological characteristics. These isolates possessed significant in vitro hydrolytic enzyme activities;
however, an isolate of Caecomyces sp. from elephant was found to exhibit maximum activity, i.e., filter paper cellulase (Fpase; 21.4 mIU/ml), carboxymethyl
cellulose (CMCase; 15.1 mIU/ml), cellobiase (37.4 mIU/ml), and xylanase (26.0 mIU/ml). Besides, this isolate also showed the
significantly highest ability to digest plant cell-wall contents in vitro. The in vitro dry matter digestibility increased
from 45.1 to 48.9% after 48 h of incubation, and the plant cell-wall contents, in terms of neutral detergent fiber and acid
detergent fiber, decreased from 64.2 to 61.3% and from 31.3 to 29.6%, respectively. These results indicate that such fibrolytic
ruminal fungal strains are prevalent in wild herbivores such as elephants, as well as in other ruminants and non-ruminants,
and could be exploited as microbial feed additives for improved nutrition and productivity in domesticated ruminants. 相似文献
160.
Farrar CT Kamoun WS Ley CD Kim YR Catana C Kwon SJ Rosen BR Jain RK Sorensen AG 《PloS one》2011,6(3):e17228
MRI biomarkers of tumor edema, vascular permeability, blood volume, and average vessel caliber are increasingly being employed to assess the efficacy of tumor therapies. However, the dependence of these biomarkers on a number of physiological factors can compromise their sensitivity and complicate the assessment of therapeutic efficacy. Here we examine the response of these MRI tumor biomarkers to cediranib, a potent vascular endothelial growth factor receptor (VEGFR) inhibitor, in an orthotopic mouse glioma model. A significant increase in the tumor volume and relative vessel caliber index (rVCI) and a slight decrease in the water apparent diffusion coefficient (ADC) were observed for both control and cediranib treated animals. This contrasts with a clinical study that observed a significant decrease in tumor rVCI, ADC and volume with cediranib therapy. While the lack of a difference between control and cediranib treated animals in these biomarker responses might suggest that cediranib has no therapeutic benefit, cediranib treated mice had a significantly increased survival. The increased survival benefit of cediranib treated animals is consistent with the significant decrease observed for cediranib treated animals in the relative cerebral blood volume (rCBV), relative microvascular blood volume (rMBV), transverse relaxation time (T2), blood vessel permeability (K(trans)), and extravascular-extracellular space (ν(e)). The differential response of pre-clinical and clinical tumors to cediranib therapy, along with the lack of a positive response for some biomarkers, indicates the importance of evaluating the whole spectrum of different tumor biomarkers to properly assess the therapeutic response and identify and interpret the therapy-induced changes in the tumor physiology. 相似文献