Palladium-catalyzed carbonylation. A new synthesis of .alpha.-methylene .gamma.-, .delta.-, .epsilon.-lactams and lactones including bicyclic lactams of pyrrolizidine and indolizidine skeletons
Ni-Catalyzed Reductive 1,2-Cross-Dialkylation of Unactivated Alkenes with Two Alkyl Bromides
作者:Jian-Xin Zhang、Wei Shu
DOI:10.1021/acs.orglett.2c01416
日期:2022.6.3
Cross-dialkylation of unactivatedalkenes represents a significant challenge due to competitive β-hydride elimination and associated selectivity issues. Herein, a Ni-catalyzed reductive 1,2-dialkylation of unactivated aliphatic alkenes has been developed using two different alkyl bromides. The reaction proceeds smoothly under mild conditions to install two Csp3–Csp3 bonds onto directed aliphatic alkenes, demonstrating
由于竞争性 β-氢化物消除和相关的选择性问题,未活化烯烃的交叉二烷基化是一项重大挑战。在此,已使用两种不同的烷基溴开发了未活化的脂肪族烯烃的镍催化还原 1,2-二烷基化。该反应在温和条件下顺利进行,将两个 C sp3 -C sp3键安装到定向脂肪族烯烃上,表现出优异的化学和区域选择性和良好的官能团耐受性。
Co-Catalyzed Synthesis of 1,4-Dicarbonyl Compounds Using TBHP Oxidant
作者:Feng Zhang、Peng Du、Jijun Chen、Hongxiang Wang、Qiang Luo、Xiaobing Wan
DOI:10.1021/ol5004687
日期:2014.4.4
A Co-catalyzed reaction for the construction of 1,4-dicarbonyls has been reported in which cascade organo-cobalt addition/trapping/Kornblum-DeLaMare rearrangement were involved. In view of the easy availability of starting materials, wide substrate scope, high functionality tolerance, and operational simplicity, this protocol constituted a simple, practical, and powerful alternative compared with previous approaches.
Antitumor agents 292. Design, synthesis and pharmacological study of S- and O-substituted 7-mercapto- or hydroxy-coumarins and chromones as potent cytotoxic agents
作者:Ying Chen、Hong-Rui Liu、Hong-Shan Liu、Ming Cheng、Peng Xia、Keduo Qian、Pei-Chi Wu、Chin-Yu Lai、Yi Xia、Zheng-Yu Yang、Susan L. Morris-Natschke、Kuo-Hsiung Lee
DOI:10.1016/j.ejmech.2011.12.025
日期:2012.3
Thirty-five S- and O-substituted 7-mercaptocoumarin (9-23) and 7-hydroxy- or 7-mercapto-chromone (24-43) analogs were designed, synthesized and evaluated in vitro against four human tumor cell lines [KB (nasopharyngeal), KB-vin (vincristine-resistant subline), A549 (lung) and DU145 (prostate)] with paclitaxel as the positive control. Many of the synthesized compounds exhibited potent cytotoxic activity. Among them, compounds 10 and 18 showed broad spectrum activity with GI(50) values ranging from 0.92 to 2.11 mu M and 2.06-14.07 mu M, respectively. However, 33, a 3-brominated compound, displayed significant and selective inhibition against MDR KB-vin with a GI(50) of 5.84 mu M. Regardless of the size of the 7-alkoxy group, 2-alpha-bromoethyl-8-bromomethyl compounds (40-43) exhibited increased cytotoxicity compared with 2-ethyl-8-bromomethyl compounds (36-39). Moreover, in a preliminary pharmacological study, 10 not only remarkably increased cellular apoptosis in a concentration-dependent manner, but also clearly induced A549 cell cycle arrest at the G2/M phase. Thus, these coumarin derivatives merit investigation as novel potential antitumor agents with further structural modification to produce an optimal lead compound and elucidate the detailed pharmacological mechanism(s). (C) 2011 Elsevier Masson SAS. All rights reserved.
MORI, MIWAKO;WASHIOKA, YUMIKO;URAYAMA, TAKAO;YOSHIURA, KAGARI;CHIBA, KATS+, J. ORG. CHEM., 1983, 48, N 22, 4058-4067