排序方式: 共有60条查询结果,搜索用时 15 毫秒
11.
Aicha Mhamdi 《Green Chemistry Letters and Reviews》2018,11(1):12-17
A green and versatile method for the preparation of γ-hydroxyphosphonate and phosphine oxide derivatives in 5?min, is accomplished through the reduction of γ-phosphonylketones with sodium borohydride supported on alumina, at room temperature, under solvent free conditions. 相似文献
12.
13.
Aicha Benabad Karima Bakhous Fatima Cherkaoui Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(11):1292-1293
BiV0.4Fe3IIIO(PO4)3 crystallizes with two Fe atoms (one on an inversion centre and one on a mirror plane) displaying octahedral geometry and a third Fe atom (on a mirror plane) with trigonal bipyramidal coordination. Fe atoms are seen in oxygen‐bridged chains. BiV atoms are found in the interstitial sites between these chains. Bi shows sevenfold coordination, with Bi—O distances between 2.357 (7) and 2.529 (6) Å. 相似文献
14.
Bareche Aicha Cherfaoui Mouloud 《Methodology and Computing in Applied Probability》2019,21(4):1259-1281
Methodology and Computing in Applied Probability - We are interested in the approximation of the ruin probability of a classical risk model using the strong stability method. Particularly, we study... 相似文献
15.
Aicha Bouratoua Assia Khalfallah Chawki Bensouici Zahia Kabouche Abdulmagid Alabdul Magid Dominique Harakat 《Natural product research》2018,32(16):1873-1880
This is the first study on the phytochemistry and antioxidant activity of Ferula longipes Coss. ex Bonnier and Maury (Apiaceae). A new flavonoid quercetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-[2-O-caffeoyl]-glucopyranoside (1), along with 10 known compounds kaempferol-3-O-α-L-rhamnopyranoside (2), quercetin-3-O-α-L-rhamnopyranoside (3), kaempferol-3-O-ß-D-glucopyranoside-7-O-α-L-rhamnopyranoside (4), isorhamnetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-glucopyranoside (5), quercetin-3-O-α-L-rhamnopyranoside-7-O-ß-D-glucopyranoside (6), isorhamnetin-3,7-di-O-β-D-glucopyranoside (7), apigenin (8), apigenin-7-O-ß-D-glucopyranoside (9), 3,5-dicaffeoylquinic acid (10), deltoin (11) were isolated from the aerial parts of Ferula longipes Coss. Structures elucidation was performed by comprehensive 1D and 2D NMR analyses, mass spectrometry and by comparison with literature data. The compounds 1, 3, 4, 6, 7 and 10 were evaluated for their antioxidant activity, compound 1 exhibited the best antiradical activity potential and showed IC50 and A0.5 values 5.70, 7.25, 5.00, and 2.63 μg/mL towards DPPH free radical-scavenging, ABTS, CUPRAC, and reducing power assays, respectively compared with BHA, BHT and ascorbic acid which were used as positive controls. 相似文献
16.
Dr. Aicha Boudhar Dr. Mélanie Charpenay Dr. Gaëlle Blond Dr. Jean Suffert 《Angewandte Chemie (International ed. in English)》2013,52(49):12786-12798
The scaffold of fenestranes is quite unique, as it contains four condensed cycles and a distorted tetracoordinated central carbon atom with bond angles greater than the regular 109°28“. In this Minireview, a detailed overview on the developments regarding this compound class, including their synthesis, is given for the time period since 2006. In the past years, natural products that belong to the class of heterofenestranes have been isolated and their syntheses will also be discussed. 相似文献
17.
18.
Aicha El Maadi Ali Boukhari Elizabeth M. Holt 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):i141-i143
The structure of the title mixed trimetallic diphosphate, K2Sr3Mn2(P2O7)3, is constructed of a three‐dimensional matrix composed of SrO8–10, MnO5 and PO4 polyhedra. The sharing of O atoms between these polyhedra creates tunnels of large dimensions parallel to (010), in which are found columns of K+ ions. Thus, the presence of several cations differing in size in the solid matrix leads to the formation of large tunnels and potential conductivity. 相似文献
19.
Aicha Yacouta-Nour Mohsen M. Mostafa Abobaker K. T. Maki 《Transition Metal Chemistry》1990,15(1):34-38
Summary Several new uranyl(VI) complexes of hydrazones, derived from formoyl-, acetoyl-, butroyl-, caproyl-, salicyloyl-, oxaloyldi-, malonoyldi-, and adipolyldi-hydrazines and benzaldehyde or salicylaldehyde have been prepared in absolute EtOH and in the presence or absence of AcONa. The complexes have been characterized by elemental analyses, molar conductivities, spectral (u.v., i.r, n.m.r.,) and magnetic measurements. I.r. spectral data suggest that the ligands coordinate in a bi-, tri- and/or tetradentate fashion in the enol form, and that proton displacement proceedsvia the enolized carbonyl oxygen solely in the benzaldehyde hydrazone complexes and through the OH (phenolic) in the salicylaldehyde hydrazone complexes. Moreover, the spectral data show the existence of dihydroxo bridges for benzaldehyde hydrazone complexes. The role of the OH (phenolic) as well as the presence or absence of NaOAc on the properties of the latter complexes is discussed. 相似文献
20.
Djellouli Fayrouz Dahmani Abdallah Hassani Aicha 《Journal of Thermal Analysis and Calorimetry》2017,130(3):1585-1591
Journal of Thermal Analysis and Calorimetry - Polymorphic transformation in Trimethoprim (TMP) drug has been studied employing differential scanning calorimetry (DSC), TG/DSC, X-ray diffraction and... 相似文献