Tri- and dibromination of methyl-, dimethyl-, and trimethylbenzenes with N-bromosuccinimide were accomplished by photothermal reaction with a tungsten lamp in carbon tetrachloride or benzene. (Dibromomethyl)arenes and (tribromomethyl) derivatives were produced depending upon a solvent used and a substituent on the benzene ring. In the bromination of methylbenzenes without a substituent on the ortho-position, (tribromomethyl)benzenes were formed. On the other hand, ortho-substituted methylbenzenes gave (dibromomethyl)benzenes. α,β-Dibromo-1,2-diarylstilbenes were formed via the debrominative carbon–carbon coupling reaction of (tribromomethyl) benzenes upon irradiation with a tungsten lamp.
On the Total Synthesis and Determination of the Absolute Configuration of Rishirilide B: Exploitation of Subtle Effects to Control the Sense of Cycloaddition of o-Quinodimethides
作者:Kana Yamamoto、Martin F. Hentemann、John G. Allen、Samuel J. Danishefsky
DOI:10.1002/chem.200304931
日期:2003.7.21
The totalsynthesis of racemic rishirilide B has been accomplished. The synthesis serves to define the relative relationships of its stereogenic centers. Also, starting with readily available chiral pool, ent-rishirilide B was synthesized, thereby demonstrating that natural configuration of rishirilide B. The defining step in our totalsynthesis is the facile cycloreversion of the bis(siloxy)benzocyclobutane
Design, synthesis and evaluation of a series of 5-methoxy-2,3-naphthalimide derivatives as AcrB inhibitors for the reversal of bacterial resistance
作者:Chaobin Jin、Rawaf Alenazy、Yinhu Wang、Rumana Mowla、Yinhui Qin、Jin Quan Eugene Tan、Natansh Deepak Modi、Xinjie Gu、Steven W. Polyak、Henrietta Venter、Shutao Ma
DOI:10.1016/j.bmcl.2019.02.003
日期:2019.4
A series of novel 5-methoxy-2,3-naphthalimide derivatives were designed, synthesized and evaluated for their biological activities. In particular, the ability of the compounds to synergize with antimicrobials, to inhibit Nile Red efflux, and to target AcrB was assayed. The results showed that the most of the tested compounds more sensitized the Escherichia coli BW25113 to the antibiotics than the parent compounds 7 c and 15, which were able to inhibit Nile Red efflux. Significantly, compound A5 possessed the most potent antibacterial synergizing ac-tivity in combination with levofloxacin by 4 times and 16 times at the concentration of 8 and 16 mu g/mL, re-spectively, whilst A5 could effectively abolish Nile Red efflux at 100 mu M. Additionally, target effect of A5 was confirmed in the outer- or inner membrane permeabilization assays. Therefore, A5 is an excellent lead com-pound for further structural optimization.
Mataka Shuntaro, Liu Guo-Bin, Sawada Tsuyoshi, Kurisu Masayoshi, Tashiro +, Bull. Chem. Soc. Jap, 67 (1994) N 4, S 1113-1119
作者:Mataka Shuntaro, Liu Guo-Bin, Sawada Tsuyoshi, Kurisu Masayoshi, Tashiro +