A flexible, highly efficient method for the preparation of homochiral oxazaphospholidine-boranes
摘要:
An efficient and operationally simple procedure for the synthesis of 2-substituted 3,4-dimethyl-5-phenyloxazaphospholidine derivatives has been developed. This new method permits the large scale preparation of a range of electronically and sterically differentiated homochiral monophosphine precursors.
Relative Basicities of ortho-, meta-, and para-Substituted Aryllithiums
摘要:
The relative basicities of aryllithiums bearing methoxy, chlorine, fluorine, trifluoromethyl and trifluoromethoxy substituents at the ortho, meta, and para positions have been assessed. To this end, two aryllithiums of comparable basicity were equilibrated together with the corresponding bromo- or iodoarenes in a 1: 2 mixture of pentanes with tetrahydrofuran at -50, -75, or -100 degrees C. The "basicity" (protodelithiation) increments Delta Delta G derived from the equilibrium constants are linearly correlated with the relative protonation enthalpies of the corresponding aryl anions in the gas phase. However, the correlation factor proves to be position-dependent. Compared with "naked" aryl anions, the basicity of aryllithiums mirrors the effects of ortho, meta, and para substituents to the extent of 36%, 30%, and 25%, respectively.
1,1-Diarylalkenes as anticancer agents: Dual inhibitors of tubulin polymerization and phosphodiesterase 4
摘要:
A series of 1,1-diarylalkene derivatives were prepared to optimize the properties of CC-5079 (1), a dual inhibitor of tubulin polymerization and phosphodiesterase 4 (PDE4). By using the 3-ethoxy-4-methoxyphenyl PDE4 pharmacophore as one of the aromatic rings, a significant improvement in PDE4 inhibition was achieved. Compound 28 was identified as a dual inhibitor with potent PDE4 (IC(50) = 54 nM) and antitubulin activity (HCT-116 IC(50) = 34 nM and tubulin polymerization IC(50) similar to 1 mu M). While the nitrile group at the alkene terminus was generally required for potent antiproliferative activity, its replacement was tolerated if there was a hydroxyl or amino group on one of the aryl rings. Conveniently, this group could also serve as a handle for amino acid derivatization to improve the compounds' solubility. The glycinamide analog 45 showed significant efficacy in the HCT-116 xenograft model, with 64% inhibition of tumor growth upon dosing at 20 mg/kg qd. (C) 2011 Elsevier Ltd. All rights reserved.
Hydroxamic acid derivatives as metalloprotease inhibitors
申请人:Burns M. David
公开号:US20050250789A1
公开(公告)日:2005-11-10
The present invention provides compounds of Formula I or II:
salt form or prodrug thereof, wherein variables are defined herein, that are modulators of metalloproteases such as matrix metalloproteases (MMPs) and ADAMs. The compounds or compositions described herein can be used to treat diseases associated with metalloprotease activity including, for example, arthritis, cancer, cardiovascular disorders, skin disorders, inflammation or allergic conditions.
2-bis(diphenylphosphino)benzene), substituents of increasing van der Waals volumes have been introduced into the ortho- or meta-positions of the platinum-bonded phenyl rings in order to influence the relative orientations of these rings with espect to the plane defined by the four valences of the central platinum. The consequences of the different conformations on the photochemical elimination of the biphenyl
(254 nm) smoothly yielded hexahydrofluorenones and related structures. This photo‐Nazarov reaction could also be applicable to the substrates carrying β‐alkyl groups on the enone, which gave corresponding polycyclic rings containing quaternary centers. These photo‐electrocyclized products may prove useful for synthesizing a variety of natural products and their derivatives. Further application of this
Resorcin derivatives, process for their preparation and pharmaceutical
申请人:Richter Gedeon Vegyeszeti Gyar Rt.
公开号:US04510338A1
公开(公告)日:1985-04-09
The invention relates to new resorcin derivatives of the formula (I) ##STR1## wherein R.sub.1 and R.sub.2 independently represent hydrogen, halogen, trihalomethyl, alkyl having from one to 3 carbon atoms or alkoxy having from one to 3 carbon atoms. According to another aspect of the invention there are provided processes for the preparation of these compounds. The compounds of the formula (I) are pharmacologically active. In particular, they are suitable for the treatment of acute ethanolic intoxication. Pharmaceutical compositions containing them as active ingredient are also within the scope of the invention.
Fundamental Study on Arsenic(III) Halides (AsX<sub>3</sub>; X = Br, I) toward the Construction of <i>C</i><sub>3</sub>-Symmetrical Monodentate Arsenic Ligands
Arsenicligands have attracted considerable attention in coordination chemistry. Arsenic(III) halides are the most important starting materials in the preparation of monodentate arsenicligands. In this work, we optimized the synthetic methodologies of arsenic(III) halides (AsX3; X = Br, I) and examined the difference of their physical properties such as solubility to organic solvent and reactivity
砷配体在配位化学中引起了相当大的关注。卤化砷(III)是制备单齿砷配体的最重要原料。在这项工作中,我们优化了卤化砷(III)(AsX 3; X = Br,I)的合成方法,并研究了其物理性质的差异,例如对有机溶剂的溶解度和对亲核试剂的反应性。此外,用获得的AsX 3制备了多种单齿砷配体。最后,将所获得的单齿砷配体用于与卟啉的反应体系中的无铜Sonogashira交叉偶联反应。结果表明,单齿砷配体比三苯基膦具有更高的催化活性,这是由于砷和磷原子之间的孤对电子特性不同。