Abstract Along with known flavonoid aglycones, the frond exudate of N. greggii yielded two ocotillol-type dammarane triterpenoids, whose structure was established by chemical reactions, spectral data and X-ray analysis.
摘要 与已知的黄酮苷元一起,N. greggii 的叶状分泌物产生了两种 ocotillol 型达马烷三萜类化合物,其结构是通过化学反应、光谱数据和 X 射线分析确定的。
Synthesis and biological evaluation of novel ocotillol-type triterpenoid derivatives as antibacterial agents
A novel class of ocotillol-type triterpenoid derivatives have been synthesized and evaluated for their in vitro antibacterial activity against several representative pathogenic bacterial strains. Compounds 20(S)-protopanaxadiol (PPD), 3, 5,16 and 24 exhibited potent antibacterial activity against Gram-positive bacteria. Compounds 3 and 5 also displayed promising antibacterial activity against a community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA; strain USA300). Furthermore, compounds PPD, 3 and 16 combined with two commercially available antibiotics kanamycin and chloramphenicol showed strong synergistic inhibitory effects at their sub-MIC concentrations against S. aureus USA300 and Bacillus subtilis 168. Additionally, cytotoxic activity assay showed that the compounds tested did not affect cell viability of the human epithelial kidney (HEK-293) and human cervical (HeLa) cells at their MICs. (C) 2013 Elsevier Masson SAS. All rights reserved.
new series of amino acid-containing derivatives were produced from 12-dehydropyxinol, a pyxinol oxidation metabolite, and its anti-inflammatory activity was assessed using an NO inhibition assay. Interestingly, the dehydrogenation at C-12 of pyxinol derivatives improved their potency greatly. Furthermore, half of the derivatives exhibited better NO inhibitory activity than hydrocortisone sodium succinate
Pyxinol 骨架是在人肝脏中由 20S-原人参二醇(人参皂苷的主要活性苷元)形成的抗炎剂的有前途的框架。在本研究中,从 12-脱氢比西诺(一种比西诺氧化代谢物)生产了一系列新的含氨基酸衍生物,并使用 NO 抑制试验评估了其抗炎活性。有趣的是,pyxinol 衍生物的 C-12 脱氢大大提高了它们的效力。此外,一半的衍生物表现出比氢化可的松琥珀酸钠(一种糖皮质激素药物)更好的 NO 抑制活性。构效关系分析表明氨基酸残基的种类及其亲水性在很大程度上影响活性,C-24的R/S立体化学也是如此。在各种衍生品中,具有 N-Boc 保护的苯丙氨酸残基的 5c 显示出最高的 NO 抑制活性和相对较低的细胞毒性。此外,衍生物 5c 可以通过 MAPK 和 NF-κB 通路而非 GR 通路剂量依赖性地抑制 iNOS、IL-1β 和 TNF-α。总的来说,pyxinol 衍生物具有作为抗炎剂应用的潜力。