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Mohammed A.E. Sallam 《Carbohydrate research》1980,85(1):93-105
Dehydration of D-galacto-2-heptulose phenylosazone with methanolic sulfuric acid afforded two 3,6-anhydro-osazone derivatives (2 and 3). Compound 2 was obtained as the preponderant isomer, without inversion at C-1 (C-3 of the starting osazone), and 3 was obtained with inversion. The anomeric configurations of 2 and 3 were determined by n.m.r. spectroscopy. Refluxing of 2 and 3 with copper sulfate afforded two C-nucleoside analogs, namely, 4-β- and 4-α- D-lyxofuranosyl-2-phenyl-1,2,3-triazole, 4 and 5, respectively. The anomeric configurations of 4 and 5 were determined by n.m.r and c.d. spectroscopy. Acetylation of 4 and 5 afforded the tri-O-acetyl derivatives. The mass spectra of these compounds were discussed. 相似文献
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Ehab HASSANEEN Alaa El‐Din SALLAM Ahmad ABO‐GHALIA Yoshiyuki MORIYAMA Kenji TOMIOKA 《Entomological Science》2011,14(3):278-282
Pigment‐dispersing factor (PDF) is an important neurotransmitter in insect circadian systems. In the cricket Gryllus bimaculatus, it affects nocturnal activity, the free‐running period and photic entrainment. In this study, to investigate whether these effects of PDF occur through a circadian molecular machinery, we measured mRNA levels of clock genes period (per) and timeless (tim) in crickets with pdf expression knocked‐down by pdf RNAi. The pdf RNAi decreased per and tim mRNA levels during the night to reduce the amplitude of their oscillation. The phase of the rhythm advanced by about 4 h in terms of trough and/or peak phases. On the other hand, pdf mRNA levels were little affected by per and tim RNAi treatment. These results suggest that PDF affects the circadian rhythm at least in part through the circadian molecular oscillation while the circadian clock has little effect on the pdf expression. 相似文献
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Ali Zainab A. Yasseen Akeel A. McAllister Katherine A. Al-Dujailli Arafat Al-Karaqully Ahmed J. Jumaah Alaa S. 《Molecular biology reports》2022,49(7):6019-6028
Molecular Biology Reports - Autism spectrum disorder (ASD) is an increasing concern among the Iraqi Arab population. The genetic alterations that cause ASD are likely to converge at the synapse.... 相似文献
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Habib Insan Anjum Farah Mohammad Taj Sulaimani Md Nayab Shafie Alaa Almehmadi Mazen Yadav Dharmendra Kumar Sohal Sukhwinder Singh Hassan Md Imtaiyaz 《Molecular and cellular biochemistry》2022,477(5):1361-1370
Molecular and Cellular Biochemistry - Head and neck squamous cell carcinoma (HNSCC) is a prevalent malignancy with a poor prognosis, whose biomarkers have not been studied in great detail. We have... 相似文献
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Summary When analytical reagent grade chemicals were used in the preparation of the fermentation medium for citric acid production, enrichment with zinc was found to be essential for establishing, good acid production addition of manganese on the other hand, was found to be inhibitory. Slight inhibition or no effect was obtained on addition of copper and iron respectively.A Greeting to the 70th Birthday of Prof. Dr. A. Rippel-Baldes. 相似文献