55386-79-3Relevant academic research and scientific papers
Solvent dependent reactivities of di-, tetra- and hexanuclear manganese complexes: Syntheses, structures and magnetic properties
Yang, Hua,Cao, Fan,Li, Dacheng,Zeng, Suyuan,Song, You,Dou, Jianmin
, p. 6620 - 6629 (2015/04/14)
An unusual solvent effect on the synthesis of five manganese complexes [Mn2(L1)2(Py)4](1), [Mn2(L1)2(DMSO)4](2), [Mn4(L2)4(OH)4](3), [Mn4(L3)2(DMSO)7(H2O)](4), and [Mn6O2(L4)4(OAc)2(OMe)2(DMSO)4]·MeOH] (5), (H3L1 = 5-(2-oxyphenyl)-pyrazole-3-carboxylic acid; H2L2 = 5-(2-oxyphenyl)-pyrazole-3-carboxylic acid amide; H4L3 = di-[5-(2-oxyphenyl)-pyrazole]-3-hydroxamic ether; and H2L4 = 5-(2-oxyphenyl)-pyrazole-3-carboxylic acid methyl ester) has been reported. Five complexes have been characterized by X-ray single crystal diffraction, IR, element analysis, thermogravimetric analysis and UV-vis spectra. The analysis reveals that complexes 1 and 2 are isostructural with a bimetallic six-membered ring and L1 from the decomposition of the original H4ppha (H4ppha = 5-(2-hydroxyphenyl)-pyrazole-3-hydroxamic acid) ligand. Complexes 3 and 4 are two tetranuclear clusters, and 3 possesses an aza12-metallacrown-4 core with L2 from the amide functionalization of the decomposition L1; while 4 represents a novel linear [Mn4N8O2] core with L3 from the condensation of L1 and H4ppha. Complex 5 is the first Mn6 cluster linked by two stacked, off-set 8-azametallacrown-3 subunits with [M-N-N-M-N-N-M-O] connectivity, and L4 derived from the esterification of L1. The magnetic behaviour of complexes 1-5 show the dominant antiferromagnetic interactions between metal centers, whereas complex 5 further reveals the coexistence of antiferromagnetic and ferromagnetic interactions, and slow magnetic relaxation at T 6 K with S = 4 ground state, as well as field induced magnetization saturation. This journal is
Chemical inducers of neurogenesis
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Page/Page column 32-33, (2009/04/24)
The present invention relates to compounds and methods for inducing neuronal differentiation in normal neural stem cells and brain cancer stem cells. The methods may take place in vitro, such as in isolates from the adult mammalian brain, or in vivo. Comp
Benzopyrones. Part 19. Synthesis and some Reactions of Ethyl 3-Bromo-4-oxochromen-2-carboxylate
Bevan, Peter S.,Ellis, Gwynn P.
, p. 1705 - 1709 (2007/10/02)
The product of the condensation of o-hydroxyacetophenone and diethyl oxalate, ethyl 2-hydroxy-4-oxochroman-2-carboxylate (13), slowly and partially isomerises in solution to the phenolic ketone (16), but in the presence of mineral acid, it is rapidly dehydrated directly to ethyl 4-oxochromen-2-carboxylate (2; R = Et).Bromination of the oxochroman (13) gave a 72:28 mixture of epimeric 3-bromo-esters.The major isomer (trans-OH,H) was readily dehydrated to give the title compound which contains a reactive bromine atom.
