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1.
Li C Lee D Graf TN Phifer SS Nakanishi Y Burgess JP Riswan S Setyowati FM Saribi AM Soejarto DD Farnsworth NR Falkinham JO Kroll DJ Kinghorn AD Wani MC Oberlies NH 《Organic letters》2005,7(25):5709-5712
[chemical reaction: see text]. Three new ent-trachylobane diterpenoids (1-3) were isolated and structures elucidated from Mitrephora glabra Scheff. (Annonaceae). Mitrephorone A (1) possesses a hexacyclic ring system with adjacent ketone moieties and an oxetane ring, both of which are unprecedented among trachylobanes. All compounds were evaluated for cytotoxicity against a panel of cancer cells, where 1 displayed the most potent and broadest activity, and against a battery of antimicrobial assays, where all compounds were approximately equipotent. 相似文献
2.
QUANTITATION OF PYRIMIDINE DIMERS BY IMMUNOSLOT BLOT FOLLOWING SUBLETHAL UV-IRRADIATION OF HUMAN CELLS 总被引:6,自引:0,他引:6
Altaf A. Wani Steven M. D'Ambrosio Nasir K. Alvi 《Photochemistry and photobiology》1987,46(4):477-482
An immunoslot blot assay was developed to detect pyrimidine dimers induced in DNA by sublethal doses of UV (254 nm) radiation. Using this assay, one dimer could be detected in 10 megabase DNA using 200 ng or 0.5 megabase DNA using 20 ng irradiated DNA. The level of detection, as measured by dimer specific antibody binding, was proportional to the dose of UV and amount of irradiated DNA used. The repair of pyrimidine dimers was measured in human skin fibroblastic cells in culture following exposure to 0.5 to 5 J m-2 of 254 nm UV radiation. The half-life of repair was approximately 24, 7 and 6 h in cells exposed to 0.5, 2 and 5 J m-2 UV radiation, respectively. This immunological approach utilizing irradiated DNA immobilized to nitrocellulose should allow the direct quantitation of dimers following very low levels of irradiation in small biological samples and isolated gene fragments. 相似文献
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Molecular Diversity - The terminal oxidases of the oxidative phosphorylation pathway play a significant role in the survival and growth of M. tuberculosis, targeting these components lead to... 相似文献
4.
Naiem Ahmad Wani Vivek Kumar Gupta Rajni Kant Subrayashastry Aravinda Rajkishor Rai 《Acta Crystallographica. Section C, Structural Chemistry》2014,70(8):776-779
The crystal structure of N‐[(1‐{2‐oxo‐2‐[2‐(pyrazin‐2‐ylcarbonyl)hydrazin‐1‐yl]ethyl}cyclohexyl)methyl]pyrazine‐2‐carboxamide monohydrate (Pyr‐Gpn‐NN‐NH‐Pyr·H2O), C19H23N7O3·H2O, reveals an unusual trans–gauche (tg−) conformation for the gabapentin (Gpn) residue around the Cγ—Cβ (θ1) and Cβ—Cα (θ2) bonds. The molecular conformation is stabilized by intramolecular N—H...N hydrogen bonds and weak C—H...O interactions. The packing of the molecules in the crystal lattice shows a network of strong N—H...O and O—H...O hydrogen bonds together with weak C—H...O and π–π inteactions. 相似文献
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Molecular Diversity - Tuberculosis (TB) is an infectious disease and the leading cause of death globally. The rapidly emerging cases of drug resistance among pathogenic mycobacteria have been a... 相似文献
10.
A new regime of chemical oxygen-iodine laser (COIL), high-pressure subsonic mode operation, was demonstrated using a jet-type
singlet oxygen generator (SOG). The laser output power of 342 W with chemical efficiency of 20.9% was obtained at the Cl2 flow rate of 18 mmol/s and the operating pressure of 6.4 Torr in the laser cavity. The specific energy was 3.1 J/l which
was four times higher than our supersonic device, and was comparable to the highest value for the supersonic regime. The experimental
results were in good agreement with the numerical simulation results.
Received: 26 February 1999 / Revised version: 13 July 1999 / Published online: 30 November 1999 相似文献