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排序方式: 共有373条查询结果,搜索用时 15 毫秒
71.
72.
Dr. Shota Ooi Dr. B. Adinarayana Dr. Daiki Shimizu Dr. Takayuki Tanaka Prof. Dr. Atsuhiro Osuka 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(24):9509-9513
While oxidation of 5,5′,15,15′-tetramesityl-10-10′-linked 3NH-corrole dimer with DDQ gave the corresponding triply linked 2NH-corrole tape, the use of an equimolar amount of p-chloranil as a milder oxidant resulted in the formation of a 10-10′-linked neutral 2NH-corrole radical dimer as a stable product. The stability of this peculiar product is ascribed largely to strong antiferromagnetic interaction of the two spins. Further oxidation of this diradical produced corrole tape, suggesting its involvement as a reaction intermediate to the corrole tape. Oxidation of 10-10′-linked bis-pyridine-coordinated CoIII corrole dimer with DDQ produced a cobalt corrole radical dimer and a doubly linked corrole dimer both as stable compounds bearing pyridine and cyanide axial ligands. This type of oxidative transformation involving neutral diradical intermediates is a unique reaction mechanism specific for corrole dimers. 相似文献
73.
Soo Liang Ooi Sok Cheon Pak Peter S. Micalos Emily Schupfer Catherine Lockley Mi Houn Park Sung-Joo Hwang 《Molecules (Basel, Switzerland)》2021,26(9)
Rice bran arabinoxylan compound (RBAC) is derived from defatted rice bran hydrolyzed with Lentinus edodes mycelial enzyme. It has been marketed as a functional food and a nutraceutical with health-promoting properties. Some research has demonstrated this rice bran derivative to be a potent immunomodulator, which also possesses anti-inflammatory, antioxidant, and anti-angiogenic properties. To date, research on RBAC has predominantly focused on its immunomodulatory action and application as a complementary therapy for cancer. Nonetheless, the clinical applications of RBAC can extend beyond cancer therapy. This article is a narrative review of the research on the potential benefits of RBAC for cancer and other health conditions based on the available literature. RBAC research has shown it to be useful as a complementary treatment for cancer and human immunodeficiency virus infection. It can positively modulate serum glucose, lipid and protein metabolism in diabetic patients. Additionally, RBAC has been shown to ameliorate irritable bowel syndrome and protect against liver injury caused by hepatitis or nonalcoholic fatty liver disease. It can potentially ease symptoms in chronic fatigue syndrome and prevent the common cold. RBAC is safe to consume and has no known side effects at the typical dosage of 2–3 g/day. Nevertheless, further research in both basic studies and human clinical trials are required to investigate the clinical applications, mechanisms, and effects of RBAC. 相似文献
74.
75.
Hydrodesulfurization activity of cobalt Chevrel phase sulfide catalysts has been investigated in a fixed-bed flow reactor.
Single phase cobalt Chevrel phase sulfides exhibited catalytic activity for hydrodesulfurization. Supported cobalt Chevrel
phase sulfides catalysts indicated much higher hydrodesulfurization activity and even higher than commercial CoMoS/Al2O3 catalysts. The existence of Mo6S8 and the reduced oxidation state of Mo in the cobalt Chevrel phase sulfides has been observed by XRD, LRS, and XPS.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
76.
Cover Picture: Catalyst‐Enabled Site‐Divergent Stereoselective Michael Reactions: Overriding Intrinsic Reactivity of Enynyl Carbonyl Acceptors (Angew. Chem. Int. Ed. 17/2018)
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77.
Asymmetric epoxidation of N-enoylsultams (1, 3-15) incorporating a variety of chiral sultams as the chiral induction elements with UHP/TFAA has been studied. Both diastereomeric isomers of epoxides (2, 16-28) were obtained in high yield and moderate to high optical purity. 相似文献
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79.
Takashi Ooi 《Tetrahedron letters》2004,45(23):4481-4484
Chiral organoaluminum complex 1 efficiently catalyzed the asymmetric hetero-ene reaction of commercially available 2-methoxypropene (2) with aldehydes under mild conditions to give the corresponding β-hydroxymethyl ketones 3 in good to excellent chemical yields with high enantiomeric excesses. The asymmetric catalysis of 1 was further applied to the carbonyl addition of methallylsilanes, where exclusive formation of the optically active allylic silanes 5 was achieved. 相似文献
80.
Reaction of (S)-2-(tert-butyldiphenylsilyloxy)-5-(mesyloxy)pentanal with hydroxylamine in allyl alcohol brought about simultaneous 1,3-dipolar cycloaddition of the resulting nitrone to allyl alcohol to give three diastereoisomeric adducts, from which (+)-febrifugine and (+)-isofebrifugine, potent antimalarial alkaloids, were synthesized. 相似文献