Antimycobacterial Compounds from Piper sanctum

Bioassay-guided chromatographic separation of the antimycobacterial extract of the leaves of Piper sanctum afforded 14 new compounds, identified as 2-oxo-12-(3‘,4‘-methylenedioxyphenyl)dodecane (<BO>1</BO>), 2-oxo-14-(3‘,4‘-methylenedioxyphenyl)tetradecane (<BO>2</BO>), 2-oxo-16-(3‘,4‘-methylenedioxyphenyl)hexadecane (<BO>3</BO>), 2-oxo-18-(3‘,4‘-methylenedioxyphenyl)octadecane (<BO>4</BO>), 2-oxo-14-(3‘,4‘-methylenedioxyphenyl)-trans-13-tetradecene (<BO>5</BO>), 2-oxo-16-(3‘,4‘-methylenedioxyphenyl)-trans-15-hexadecene (<BO>6</BO>), 2-oxo-18-(3‘,4‘-methylenedioxyphenyl)-trans-17-octadecene (<BO>7</BO>), 2-oxo-16-phenyl-trans-3-hexadecene (<BO>8</BO>), methyl [6-(10-phenyldecanyl)tetrahydropyran-2-yl]acetate (<BO>9</BO>), methyl 2-(6-tridecyltetrahydro-2H-pyran-2-yl)acetate (<BO>10</BO>), methyl 2-(5-tetradecyltetrahydro-2-furanyl)acetate (<BO>11</BO>), 2-oxo-14-(3‘,4‘-methylenedioxyphenyl)-trans-3-tetradecene (<BO>12</BO>), 2-oxo-16-(3‘,4‘-methylenedioxyphenyl)-trans-3-hexadecene (<BO>13</BO>), and 2-oxo-16-phenyl-3-hexadecane (<BO>14</BO>). In addition, p-eugenol (<BO>15</BO>), methyleugenol (<BO>16</BO>), Z-piperolide (<BO>17</BO>), demethoxyyangonin (<BO>18</BO>), 5,6-dehydro-7,8-dihydromethysticin (<BO>19</BO>), cepharanone B (<BO>20</BO>), piperolactam A (<BO>21</BO>), cepharadione B (<BO>22</BO>), N-trans-feruloyltyramine (<BO>23</BO>), and N-trans-(p-coumaroyl)tyramine (<BO>24</BO>) were obtained from the anti-TBC stem extract of the plant. GC-MS and HPLC analyses of the essential oils of the leaves and stem revealed that safrol (<BO>25</BO>) was the major component of the oils. Compounds <BO>2</BO>, <BO>3</BO>, <BO>6</BO>, <BO>18</BO>−<BO>21</BO>, and <BO>24</BO> inhibited the growth of Mycobacterium tuberculosis when tested by the MABA assay, with MIC values ranging from 4 to 64 μg/mL.