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排序方式: 共有293条查询结果,搜索用时 15 毫秒
1.
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Abed Al-Aziz Al-Quntar 《Journal of organometallic chemistry》2005,690(10):2504-2514
This article describes our recent methods for the synthesis of substituted vinylphosphonates by reacting 1-alkynylphosphnates with group (IV) complexes. cis-Vinylphosphonates, 1,3-butadienylphosphonates, 1-(hydroxymethyl)vinylphosphonates, 2-(hydroxymethyl)vinylphosphonates, (E) 3-oxo-1-alkenylphosphonates were produced as a result of the reactions between zirconium complexes and 1-alkynylphosphonates. On the other hand, titanium complexes afford 3-aminovinylphoshonates, 1,4-bis-phosphonates, and various other di- and tri-substituted vinylphosphonates. An evaluation of access of these recently synthesized vinylphosphonates as MMP-2 inhibitors has shown that certain compounds are very potent and promising. 相似文献
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Hydroxyapatite (HA), a natural constituent of bone, was synthesized. HA particles were radiolabeled with 188Re. Radiolabeling efficiency was 95%. In vitro studies showed 5% loss of activity from particles in normal saline over a period of 2 days, whereas a dissociation rate of 9% was observed in human serum albumin. 相似文献
5.
Dina Abed Bakhotmah 《Phosphorus, sulfur, and silicon and the related elements》2020,195(6):437-453
AbstractThis review reports the developed methods for the synthesis of polyfunctional 1,2,4-triazine systems bearing and/or containing phosphorus atoms as donor-acceptors interactions. Most of the synthetic methods depend on the interaction between an amino group of the side chain of 1,2,4-triazine with phosphorus reagents. The biological activities, i.e. their biocidal affects as antioxidants, antimicrobials, anti-inflammatory as well as molluscicidal agents against some snails are discussed. 相似文献
6.
Ahmed El Abed Etienne Gaudin Jacques Darriet 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):i138-i140
Single crystals of Sr4Mn2.09Cu0.91O9 have been grown by flux synthesis and the structure, closely related to the hexagonal perovskite 2H, was solved from single‐crystal X‐ray data in space group P321. The structure of Sr4Mn2CuO9 is composed of chains of face‐sharing polyhedra with a sequence of two octahedra and one trigonal prism. The octahedra are filled by Mn atoms and the Cu atoms are randomly distributed at the centres of the square faces of the trigonal prism. A stacking fault is observed within one of the two chains, which can be attributed to a shifting of the chain along the c axis. 相似文献
7.
Acta Mathematica Sinica, English Series - In this research article, we shall give some reverse Arithmetic-Geometric mean inequalities for unital positive linear maps on Hilbert space operators... 相似文献
8.
Coset diagrams for the orbit of the groupG=〈x,y∶x
2=y
4
=1〉 acting on real quadratic fields give some interesting information. By using these coset diagrams, we show that in the orbitpG, where
, the non-square positive integern does not change its value and the real quadratic irrational numbers of the formp, wherep and its algebraic conjugate
have different signs, are finite in number and that part of the coset diagram containing such numbers forms a single closed
path, which is the only closed path in the orbit ofp. 相似文献
9.
M. S. Mansur A. Mushtaq M. Jehangir 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(1):141-143
Summary The lyophilized MIBI kit was dissolved in 1 ml sterile saline or 250<span style='font-size: 12.0pt;font-family:Symbol;mso-bidi-font-family:Symbol'>mg/ml
ascorbic acid and dispensed into 0.2 ml fractions, which were stored at -20 °C for 12 days. The solution was prepared by using
two different protection methods. In the first method evacuated vials were used for storage of fractionated solution while
in the second method an antioxidant agent, ascorbic acid was employed. The radiochemical impurity of 99mTc-MIBI in the unprotected fractions rises with time. Exclusion of air as well addition of ascorbic acid in fractionated solutions
gave very good results. The labeling efficiency and biodistribution of fractionated solutions was the same as the lyophilized
kit even after 12 days. 相似文献
10.
Saify ZS Mushtaq N Khan KM Perveen S Shah ST Abdel-Jalil RJ Fecker M Voelter W 《Chemical & pharmaceutical bulletin》2005,53(1):64-66
A new series of 4-(4'-chlorophenyl)-4-hydroxypiperidine derivatives (2-5), substituted at nitrogen, were synthesized and tested as potential analgesic compounds as well as evaluated for their effect on hypotensive activity. Results showed that all the derivatives exhibit significant analgesic activity in male Wistar rats at a dose of 50 mg/kg of body weight after intramuscular injection, when tested by thermal stimuli (tail flick test). Pethidine was used as reference drug. Compounds 2, 3 and 5 produced reduction in blood pressure in normotensive rat. 相似文献