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Kinya Akiba - One of the best experts on this subject based on the ideXlab platform.
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a grignard type addition of allyl unit to aldehydes by using Bismuth and Bismuth Salt
Bulletin of the Chemical Society of Japan, 1990Co-Authors: Makoto Wada, Hidenori Ohki, Kinya AkibaAbstract:In the presence of metallic Bismuth, Bismuth(III) chloride–metallic zinc, or Bismuth(III) chloride–metallic iron, allylic halides have been found to react with aldehydes under mild conditions to give the corresponding homoallylic alcohols in high yields with high chemo-, regio-, and stereoselectivity. Allylic halides have been also found to react with aldehydes at room temperature in tetrahydrofuran–water by using Bismuth(III) chloride–metallic aluminium to afford the expected homoallylic alcohols in high yields.
Makoto Wada - One of the best experts on this subject based on the ideXlab platform.
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Aerobic oxidation of alcohols using Bismuth bromide as a catalyst
Tetrahedron Letters, 2019Co-Authors: Masaharu Ueno, Satoshi D. Ohmura, Makoto Wada, Norikazu MiyoshiAbstract:Abstract We developed an environmentally friendly method for aerobic oxidation of alcohols using a commercially available, relatively benign Bismuth Salt as a catalyst. We found that the catalytic combination of BiBr 3 with nitric acid is key for enhancing the reactivity. The reaction proceeds well under air, making the use of pure oxygen unnecessary. Each of the primary or secondary alcohols tested was oxidized to the corresponding aldehydes or ketones using this protocol.
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a grignard type addition of allyl unit to aldehydes by using Bismuth and Bismuth Salt
Bulletin of the Chemical Society of Japan, 1990Co-Authors: Makoto Wada, Hidenori Ohki, Kinya AkibaAbstract:In the presence of metallic Bismuth, Bismuth(III) chloride–metallic zinc, or Bismuth(III) chloride–metallic iron, allylic halides have been found to react with aldehydes under mild conditions to give the corresponding homoallylic alcohols in high yields with high chemo-, regio-, and stereoselectivity. Allylic halides have been also found to react with aldehydes at room temperature in tetrahydrofuran–water by using Bismuth(III) chloride–metallic aluminium to afford the expected homoallylic alcohols in high yields.
Donna Mctavish - One of the best experts on this subject based on the ideXlab platform.
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Omeprazole
Drugs, 1994Co-Authors: Michelle I. Wilde, Donna MctavishAbstract:Synopsis Omeprazole, a gastric acid pump inhibitor, dose-dependently controls gastric acid secretion; the drug has greater antisecretory activity than histamine H_2-receptor antagonists. Omeprazole 20 to 40 mg/day is more effective than histamine H_2-receptor antagonists in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. Available data suggest that omeprazole 10 to 40 mg/day is also more effective than ranitidine in the maintenance therapy of duodenal ulcer and reflux oesophagitis. The drug is also effective in patients with duodenal ulcer, gastric ulcer or reflux oesophagitis poorly responsive to histamine H_2-receptor antagonists. The efficacy of omeprazole 20 mg/day appears to be similar to that of lansoprazole 30 mg/day in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. However, most available studies have been reported in abstract form only, and 2 of 3 studies in patients with duodenal ulcer have shown greater healing rates at 2 (but not 4) weeks with lansoprazole. Helicobacter pylori eradication decreases duodenal ulcer relapse rates and appears to be associated with improved duodenal ulcer healing rates. Evidence also suggests that H. pylori eradication is associated with reduced gastric ulcer relapse rates. Omeprazole monotherapy may suppress but does not eradicate H. pylori infection. Eradication rates with omeprazole 20 or 40mg twice daily plus amoxicillin usually up to 2 g/day (3 g/day in a few studies) for 2 weeks appear to be similar to those of standard triple therapy (Bismuth Salt plus metronidazole, plus tetracycline or amoxicillin) or omeprazole plus clarithromycin, although eradication rates vary widely. Omeprazole plus amoxicillin appears to be better tolerated than triple therapy and represents a first-line treatment alternative in patients with H. pylori -associated peptic ulcer disease. Omeprazole plus amoxicillin plus metronidazole appears to be more effective than omeprazole plus amoxicillin in patients with metronidazole-sensitive H. pylori infection. Omeprazole remains a treatment of choice in patients with Zollinger-Ellison syndrome. The dosage should be adjusted according to individual response. However, relatively low dosages of 10 to 40 mg/day may be sufficient in some patients. The drug has also shown promise in the treatment of children with severe reflux oesophagitis, in patients with reflux oesophagitis and coexisting systemic sclerosis, and in the prevention of aspiration pneumonia. Evidence suggests that omeprazole is more effective than ranitidine in patients with nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage who continue to take NSAIDs, especially in patients with large gastric ulcers; however, completion of ongoing studies is required to verify this. Omeprazole is generally well tolerated during short (2cm in diameter) ulcers. The superior efficacy of omeprazole 20 or 40 mg/day in terms of healing and symptom resolution compared with ranitidine 150mg twice daily in the short term treatment of all grades of reflux oesophagitis, including histamine H_2-receptor antagonist-refractory disease, has also been confirmed in recent studies. Available data suggest that the efficacy of omeprazole is superior to that of ranitidine in combination with cisapride or metoclopramide, and similar to that of lansoprazole in the short term treatment of reflux oesophagitis. Recent data confirm the superiority of omeprazole over ranitidine in the prevention of recurrence of reflux oesophagitis. Further study with a low omeprazole dosage of 10 mg/day in the prevention of reflux oesophagitis recurrence is underway. Omeprazole has also shown promise in the treatment of patients with reflux oesophagitis and coexisting systemic sclerosis or peptic oesophageal strictures, and in children with severe gastro-oesophageal reflux. Although omeprazole has been shown to improve oesophagitis in patients with Barrett’s oesophagus, data on regression of the metaplasia are inconclusive. The efficacy of omeprazole in the treatment of patients with Zollinger-Ellison syndrome is well established. Relatively low omeprazole dosages of 10 to 40 mg/day may be sufficient in some patients although dosage titration is advised. Oral omeprazole 40mg on the evening before surgery plus oral omeprazole 40mg on the morning before surgery, or intravenous omeprazole 40mg 1 hour before induction of anaesthesia reduces the risk of aspiration pneumonitis during general anaesthesia. Tolerability The favourable tolerability profile of short term (
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Omeprazole. An update of its pharmacology and therapeutic use in acid-related disorders.
Drugs, 1994Co-Authors: Michelle I. Wilde, Donna MctavishAbstract:Omeprazole, a gastric acid pump inhibitor, dose-dependently controls gastric acid secretion: the drug has greater antisecretory activity than histamine H2-receptor antagonists. Omeprazole 20 to 40 mg/day is more effective than histamine H2-receptor antagonists in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. Available data suggest that omeprazole 10 to 40 mg/day is also more effective than ranitidine in the maintenance therapy of duodenal ulcer and reflux oesophagitis. The drug is also effective in patients with duodenal ulcer, gastric ulcer or reflux oesophagitis poorly responsive to histamine H2-receptor antagonists. The efficacy of omeprazole 20 mg/day appears to be similar to that of lansoprazole 30 mg/day in the short term treatment of duodenal ulcer, gastric ulcer and reflux oesophagitis. However, most available studies have been reported in abstract form only, and 2 of 3 studies in patients with duodenal ulcer have shown greater healing rates at 2 (but not 4) weeks with lansoprazole. Helicobacter pylori eradication decreases duodenal ulcer relapse rates and appears to be associated with improved duodenal ulcer healing rates. Evidence also suggests that H. pylori eradication is associated with reduced gastric ulcer relapse rates. Omeprazole monotherapy may suppress but does not eradicate H. pylori infection. Eradication rates with omeprazole 20 or 40 mg twice daily plus amoxicillin usually up to 2 g/day (3 g/day in a few studies) for 2 weeks appear to be similar to those of standard triple therapy (Bismuth Salt plus metronidazole, plus tetracycline or amoxicillin) or omeprazole plus clarithromycin, although eradication rates vary widely. Omeprazole plus amoxicillin appears to be better tolerated than triple therapy and represents a first-line treatment alternative in patients with H. pylori-associated peptic ulcer disease. Omeprazole plus amoxicillin plus metronidazole appears to be more effective than omeprazole plus amoxicillin in patients with metronidazole-sensitive H. pylori infection. Omeprazole remains a treatment of choice in patients with Zollinger-Ellison syndrome. The dosages should be adjusted according to individual response. However, relatively low dosages of 10 to 40 mg/day may be sufficient in some patients. The drug has also shown promise in the treatment of children with severe reflux oesophagitis, in patients with reflux oesophagitis and coexisting systemic sclerosis, and in the prevention of aspiration pneumonia. Evidence suggests that omeprazole is more effective than ranitidine in patients with nonsteroidal anti-inflammatory drug (NSAID)-induced gastric damage who continue to take NSAIDs, especially in patients with large gastric ulcers; however, completion of ongoing studies is required to verify this.(ABSTRACT TRUNCATED AT 400 WORDS)
Han Yuzh - One of the best experts on this subject based on the ideXlab platform.
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Catalytic Performance of Tungstate/Molybdate/Phosphotungstic/Phosphomolybdate Acid Bismuth Salt
Journal of Jishou University, 2015Co-Authors: Han YuzhAbstract:Bi2WO6,Bi2MoO6,BiPW12O40 and BiPMo12O40catalysts were synthesized by hydrothermal and co-precipitation method and characterized by IR,UV-vis,FL,SEM and X-ray power diffraction(XRD).The relationship between catalytic performance of catalysts and preparation conditions,calcination temperature and different substrates was explored.The best degradation of RhB(100mL 4mg/L)achieved98.1% over the unbaked Bi2WO6 with the W/Bi molar rate 1∶2,which also had certain catalytic effect for degrading methyl orange and methylthionine chloride.The tungstate Bismuth and molybdate Bismuth catalysts had a good catalytic effect for degrading RhB,methyl orange and methylthionine chloride as well.The catalytic performance of phosphomolybdate Bismuth was poorer.
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catalytic performance of tungstate molybdate phosphotungstic phosphomolybdate acid Bismuth Salt
Journal of Jishou University, 2015Co-Authors: Han YuzhAbstract:Bi2WO6,Bi2MoO6,BiPW12O40 and BiPMo12O40catalysts were synthesized by hydrothermal and co-precipitation method and characterized by IR,UV-vis,FL,SEM and X-ray power diffraction(XRD).The relationship between catalytic performance of catalysts and preparation conditions,calcination temperature and different substrates was explored.The best degradation of RhB(100mL 4mg/L)achieved98.1% over the unbaked Bi2WO6 with the W/Bi molar rate 1∶2,which also had certain catalytic effect for degrading methyl orange and methylthionine chloride.The tungstate Bismuth and molybdate Bismuth catalysts had a good catalytic effect for degrading RhB,methyl orange and methylthionine chloride as well.The catalytic performance of phosphomolybdate Bismuth was poorer.
Hidenori Ohki - One of the best experts on this subject based on the ideXlab platform.
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a grignard type addition of allyl unit to aldehydes by using Bismuth and Bismuth Salt
Bulletin of the Chemical Society of Japan, 1990Co-Authors: Makoto Wada, Hidenori Ohki, Kinya AkibaAbstract:In the presence of metallic Bismuth, Bismuth(III) chloride–metallic zinc, or Bismuth(III) chloride–metallic iron, allylic halides have been found to react with aldehydes under mild conditions to give the corresponding homoallylic alcohols in high yields with high chemo-, regio-, and stereoselectivity. Allylic halides have been also found to react with aldehydes at room temperature in tetrahydrofuran–water by using Bismuth(III) chloride–metallic aluminium to afford the expected homoallylic alcohols in high yields.