使用顺序糖基化方法报道了来自碳青霉烯抗性肺炎克雷伯氏菌2796和3264的CPS六糖重复单元的总合成。总合成已经通过对衍生自市售糖的合理保护的单糖合成子进行糖基化来完成。通过TEMPO介导的后期氧化,成功地在半乳糖部分上安装了所需的尿酸。使用H 2 SO 4-二氧化硅作为促进剂,通过NIS介导的硫糖苷的活化进行糖基化。氯乙酸基团被广泛用作临时保护基团,以促进立体选择性糖基化。
Synthesis and antibacterial evaluation of a series of oligorhamnoside derivatives
摘要:
A series of novel oligorhamnoside derivatives (1-10) and naturally occurring cleistrioside-5 were synthesized and evaluated for their in vitro antibacterial activities. Among them, dirhamnoside derivative 7 and cleistrioside-5 displayed similar antibacterial profiles and exhibited moderate to good inhibitory activities on bacterial growth against a panel of Gram-positive bacteria (MICs <= 4-32 mu g/mL). The results revealed that these two compounds showed selectivity towards bacterial species strictly, without being affected by the antibiotic-resistant/susceptible properties of one species, which suggested that they might have the potential to avoid antibiotic cross-resistance. In addition, the preliminary SARs of this type of oligorhamnoside derivatives on the antibacterial activities were determined. (C) 2011 Elsevier Ltd. All rights reserved.