Synthesis and antimicrobial evaluation of a series of 7-[3-amino (or aminomethyl)-4-aryl (or cyclopropyl)-1-pyrrolidinyl]-4-quinolone and -1,8-naphthyridone-3-carboxylic acids
摘要:
A series of 6-fluoroquinolone- and 6-fluoro-1,8-naphthyridone-3-carboxylic acids possessing a [3-amino (or aminomethyl)-4-aryl (or cyclopropyl)-1-pyrrolidinyl] group at C-7 were synthesized and evaluated for their antimicrobial activity. The effect of the relative stereochemistry of the pyrrolidinyl substituents, as well as the presence of different functional groups on the 4-aryl (or cyclopropyl) moiety, was investigated in conjunction with their attachment to several quinolone or naphthyridone nuclei. In general, the incorporation of substituents on the aryl (or cyclopropyl) ring decreased in vitro and in vivo activity, regardless of the nature and relative position of the substituent. Bulky, lipophilic groups and substitution at the 2- and 3-position of the aromatic ring were particularly deleterious. Within a limited subset of derivatives, cis substitution of the pyrrolidine ring was less favorable than trans substitution. The majority of these effects were more apparent against the Enterobacteriaceae than against any other Gram-negative or Gram-positive organism and could be associated with negative interactions related to permeability or transport factors.
1,4‐Addition of TMSCCl
<sub>3</sub>
to Nitroalkenes: Efficient Reaction Conditions and Mechanistic Understanding
作者:Na Wu、Benoit Wahl、Simon Woodward、William Lewis
DOI:10.1002/chem.201402394
日期:2014.6.16
formation of the 1,4‐addition product, suggesting the reaction proceeds via a transient [Me3Si(alkene)CCl3] species, in which (alkene) indicates an Si⋅⋅⋅O coordinated nitroalkene. The anaerobic catalytic chain is propagated through the kinetic nitronate anion resulting from 1,4 CCl3− addition to the nitroalkene. This is demonstrated by the fact that isolated NBu4[CH2NO2] is an efficient promoter. Use
改进的合成条件允许以良好的产率 (70%) 和优异的纯度制备 TMSCCl 3。NBu 4 X [X=Ph 3 SiF 2 (TBAT)、F(四丁基氟化铵,TBAF)、OAc、Cl 和 Br]类型的化合物作为催化促进剂,用于对一系列环状和非环状硝基烯烃进行 1,4-加成, 在 0–25 °C 的 THF 中,通常具有中等至极好的收率 (37–95%)。TBAT 是最有效的促进剂,而溴化物最不有效。厌氧条件下的多核 NMR 研究(1 H、19 F、13 C 和29 Si)表明将 TMSCCl 3 添加到 TBAT(均为 0.13 M) 在 -20 °C 下,在没有硝基烯烃的情况下,立即导致 Me 3 SiF、Ph 3 SiF 和 NBu 4 CCl 3 的混合物。后者至少在 0 °C 下是稳定的,并且即使在延长的时间后,也不会在 -20 到 0 °C 之间添加硝基烯烃。硝基烯烃在 TMSCCl
Efficient and Stereoselective Nitration of Mono- and Disubstituted Olefins with AgNO<sub>2</sub> and TEMPO
common and versatile reagent. Its synthesis from olefin is generally limited by the formation of mixture of cis and trans compounds. Here we report that silver nitrite (AgNO2) along with TEMPO can promote the regio- and stereoselective nitration of a broad range of olefins. This work discloses a new and efficient approach wherein starting from olefin, nitroalkane radical formation and subsequent transformations
硝基烯烃是一种常见且用途广泛的试剂。它从烯烃合成通常受到顺式和反式化合物混合物的形成的限制。在这里,我们报告亚硝酸银 (AgNO2) 与 TEMPO 一起可以促进范围广泛的烯烃的区域和立体选择性硝化。这项工作公开了一种新的有效方法,其中从烯烃开始,硝基烷烃自由基形成和随后的转化以立体选择性方式导致所需的硝基烯烃。
BENZOXAZOLE CARBOXAMIDE INHIBITORS OF POLY(ADP-RIBOSE)POLYMERASE (PARP)
申请人:Chu Daniel
公开号:US20090197863A1
公开(公告)日:2009-08-06
A compound having the structure set forth in Formula (I) or Formula (II):
wherein the variables Y, R
1
, R
2
, R
3
, and R
4
are as defined herein. Provided herein are inhibitors of poly(ADP-ribose)polymerase activity. Also described herein are pharmaceutical compositions that include at least one compound described herein and the use of a compound or pharmaceutical composition described herein to treat diseases, disorders and conditions that are ameliorated by the inhibition of PARP activity.
A straightforwardsynthesis of 1,2‐dicyanoalkanes by reacting nitroalkenes with trimethylsilyl cyanide in the presence of tetrabutylammoniumfluoride is described. The reaction proceeds through a tandem double Michael addition under mild conditions. Employing the hypervalent silicate generated from trimethylsilyl cyanide and tetrabutylammoniumfluoride is essential for achieving this transformation