Lahorenoic Acids A–C, <i>ortho</i>-Dialkyl-Substituted Aromatic Acids from the Biocontrol Strain <i>Pseudomonas aurantiaca</i> PB-St2

Abstract

Three new aromatic acids, named lahorenoic acids A (<b>1</b>), B (<b>2</b>), and C (<b>3</b>), have been isolated along with the known compounds phenazine-1-carboxylic acid (<b>4</b>), 2-hydroxyphenazine-1-carboxylic acid (<b>5</b>), 2-hydroxyphenazine (<b>6</b>), 2,8-dihydroxyphenazine (<b>7</b>), cyclo-Pro-Tyr (<b>8</b>), cyclo-Pro-Val (<b>9</b>), cyclo-Pro-Met (<b>10</b>), and WLIP (<b>11</b>) and characterized from the biocontrol strain <i>Pseudomonas aurantiaca</i> PB-St2. The structures of these compounds were deduced by 1D and 2D NMR spectroscopic and mass spectral data interpretation. Compounds <b>2</b>, <b>4</b>, and <b>7</b> showed moderate antibacterial activity against mycobacteria and other Gram-positive bacteria, while <b>4</b> was also found to exhibit cytotoxic and antifungal properties