9,11-cycloendoperoxide pro-drugs of prostaglandin analogues for treatment of ocular hypertension and glaucoma
申请人:——
公开号:US20040023954A1
公开(公告)日:2004-02-05
9,11-Cycloendoperoxide derivatives of biologically active prostaglandin analogs, and particularly of the ocular hypotensive drugs Bimatoprost, Latanaprost, Unoprostone, Travoprost and prostaglandin H
2
1-ethanolamide or of structurally closely related analogs, are pro-drugs which hydrolyze under physiological conditions to provide prostaglandin analogues that are capable of providing sustained ocular and other in vivo concentrations of the respective drugs. The compounds of the invention have the formula shown below where the variables have the meaning defined in the specification.
1
Hindered organoboron groups in organic chemistry. 25. The condensation of aliphatic aldehydes with dimesitylboryl stabilised carbanions to give alkenes.
作者:Andrew Pelter、Keith Smith、Said M.A. Elgendy
DOI:10.1016/s0040-4020(01)87983-7
日期:1993.8
In the presence of protic acids the condensation of aliphatic aldehydes with dimesitylboryl stabilised carbanions results in alkenes. In the presence of strong acids such as HCl or CF3SO3H, the products contain > 90% of E-alkenes in all cases tried. When acetic acid is used, then Z-alkenes may result predominantly, particularly in the cases of RsCHO and RtCHO. HX HCI, CF3SO3H gives E - alkenes in
在质子酸的存在下,脂族醛与二聚三苯甲基稳定的碳负离子的缩合会生成烯烃。在强酸(例如HCl或CF 3 SO 3 H)的存在下,在所有尝试的情况下,产品均含有> 90%的E-烯烃。当使用乙酸时,则可能主要产生Z-烯烃,特别是在R s CHO和R t CHO的情况下。在所有情况下,HXHCl,CF 3 SO 3 H均会生成E-烯烃。HXCH 3 CO 2 H,使得主要ž -烯烃当Rř秒,R叔。
Phosphonium-based ionic liquids: Economic and efficient catalysts for the solvent-free cycloaddition of CO2 to epoxidized soybean vegetable oil to obtain potential bio-based polymers precursors
these ionicliquids was compared to the widely used and benchmark catalyst in CO2 cycloaddition to epoxides reaction, namely tetrabutylammonium bromide at different reaction conditions. The influence of some reaction parameters such as temperature, CO2 pressure, reaction time and catalyst amount was studied. It has been found that the solubility of the prepared ionicliquids in the reaction media (epoxidized
一系列基于鏻的离子液体以一种简单的方式从廉价的原料中一步制备。所制备的离子液体已成功地在 CO 2与环氧化大豆油的无溶剂环加成反应中作为催化剂进行测试,以获得碳酸豆油,该油可潜在地用作生物基聚合物合成中的生物单体。将这些离子液体的催化性能与CO 2环加成到环氧化物反应中广泛使用的基准催化剂,即在不同反应条件下的四丁基溴化铵进行了比较。温度、CO 2等反应参数的影响对压力、反应时间和催化剂用量进行了研究。已经发现,制备的离子液体在反应介质(环氧化大豆油)中的溶解度是限制一些合成离子液体催化性能的关键因素。所有制备的离子液体都表现出比基准催化剂更高的热稳定性,其中三种表现出优异的催化性能。十二烷基三苯基溴化鏻 ( 5 )在转化率和选择性方面获得了最佳结果,在160 ºC和40 bar CO 2 条件下反应5 小时后,几乎完全转化 ( 99.8% ) 和出色的选择性 ( 84.0% )。 . 与文献中报道的那些相比,在无溶剂CO
Simple salts of abundant metals (Fe, Bi, and Ti) supported on montmorillonite as efficient and recyclable catalysts for regioselective intramolecular and intermolecular hydroalkoxylation reactions of double bonds and tandem processes
conditions has been studied using two types of solid catalysts, namely montmorillonite (MMT) doped with metal cations and metal nanoparticles supported on oxides. In the case of intramolecular reactions, 38–99% yields of cyclic ethers have been obtained using Fe-MMT and Bi-MMT both in CH3NO2 and dimethyl carbonate (DMC) compared with other supported metal salts or metal nanoparticles. In the case of more challenging
已经使用两种类型的固体催化剂,即掺杂有金属阳离子的蒙脱石(MMT)和负载在氧化物上的金属纳米颗粒,研究了烯烃的催化加氢烷氧基化反应从均相转化为非均相条件的过程。在分子内反应的情况下,在CH 3 NO 2中使用Fe-MMT和Bi-MMT均可获得38-99%的环状醚收率碳酸二甲酯(DMC)与其他负载型金属盐或金属纳米粒子相比。在更具挑战性的分子间反应的情况下,使用金属掺杂的MMT(例如Fe-,Bi-和Ti-MMT)也可以获得高达72%的转化率和高达54%的产率。在本文中,我们详细介绍了被识别为真正异质催化过程的底物范围和限制,适用于两类反应和串联过程,它们在流动中的移位以及有关活性物质的一些机理见解。作为一般趋势,观察到三取代的双键在分子内和分子间反应中均能获得最佳结果。在Fe-MMT和Bi-MMT的情况下,均相催化剂成功转移到非均相催化剂上,在Bi-MMT的情况下,甚至可以提高催化活性。
Convenient synthesis of d- and l-xylo-1,2,3,4-alkane tetrols from a d-gluco-configured common building block
D-gluco-configured buildingblock derived from D-(+)-gluconolactone has served as a common chiral template for the synthesis of enantiopure D- and L-xylo-configured 1,2,3,4-alkane tetrols. This has enabled synthesis of medicinally important guggultetrols and their enantiomers from a common starting point. Wittig and Grignard reactions are the key steps used for the incorporation of lipophilic chain