Structure activity relationship, acute toxicity and cytotoxicity of antimycobacterial neolignan analogues

J Pharm Pharmacol. 2011 Jul;63(7):936-42. doi: 10.1111/j.2042-7158.2011.01290.x. Epub 2011 May 19.


Objectives: The study's aims were to evaluate the antimycobacterial activity of 13 synthetic neolignan analogues and to perform structure activity relationship analysis (SAR). The cytotoxicity of the compound 2-phenoxy-1-phenylethanone (LS-2, 1) in mammalian cells, such as the acute toxicity in mice, was also evaluated.

Methods: The extra and intracellular antimycobacterial activity was evaluated on Mycobacterium tuberculosis H37Rv. Cytotoxicity studies were performed using V79 cells, J774 macrophages and rat hepatocytes. Additionally, the in-vivo acute toxicity was tested in mice. The SAR analysis was performed by Principal Component Analysis (PCA).

Key findings: Among the 13 analogues tested, LS-2 (1) was the most effective, showing promising antimycobacterial activity and very low cytotoxicity in V79 cells and in J774 macrophages, while no toxicity was observed in rat hepatocytes. The selectivity index (SI) of LS-2 (1) was 91 and the calculated LD50 was 1870 mg/kg, highlighting the very low toxicity in mice. SAR analysis showed that the highest electrophilicity and the lowest molar volume are physical-chemical characteristics important for the antimycobacterial activity of the LS-2 (1).

Conclusions: LS-2 (1) showed promising antimycobacterial activity and very weak cytotoxicity in cell culture, as well as an absence of toxicity in primary culture of hepatocytes. In the acute toxicity study there was an indication of absence of toxicity on murine models, in vivo.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Bacterial Agents / adverse effects
  • Anti-Bacterial Agents / chemistry*
  • Anti-Bacterial Agents / pharmacology*
  • Antitubercular Agents / adverse effects
  • Antitubercular Agents / chemistry
  • Antitubercular Agents / pharmacology
  • Cell Line
  • Cricetinae
  • Cricetulus
  • Hepatocytes / drug effects
  • Lethal Dose 50
  • Lignans / adverse effects
  • Lignans / chemistry*
  • Lignans / pharmacology*
  • Macrophages / drug effects
  • Male
  • Mice
  • Mice, Inbred BALB C
  • Microbial Sensitivity Tests
  • Mycobacterium tuberculosis / drug effects*
  • Principal Component Analysis
  • Rats
  • Rats, Wistar
  • Structure-Activity Relationship
  • Toxicity Tests, Acute


  • 2-phenoxy-1-phenylethanone
  • Anti-Bacterial Agents
  • Antitubercular Agents
  • Lignans