“…The NMR data for compound 9 are presented in this paper. The other known compounds, which are piperine ( 10 ) [22], methyl piperate ( 11 ) [23], piperanine ( 12 ) [24], pipernonaline ( 13 ) [25], piperchabamide B ( 14 ) [9], piperolein-B ( 15 ) [22], 3-phenyl-1-(piperidin-1-yl)propan-1-one ( 16 ) [17] ( E )-3-phenyl-1-(piperidin-1-yl)prop-2-en-1-one ( 17 ) [17], trans -fagaramide ( 18 ) [26], pipercide ( 19 ) [27], guineensine ( 20 ) [27], dihydropiperlonguminine ( 21 ) [25], 5,6-dihydro-1 H -pyridin-2-one ( 22 ) [28], 3-chloro-4-hydroxy-2-piperidone ( 23 ) [29], octahydro-4-hydroxy-3 α -methyl-7-methylene- α -(1-methylethyl)-1 H -indene-1-methanol ( 24 ) [30], alismoxide ( 25 ) [31] (4 S, 4a S, 6 S, 8a S )-octahydro-4-hydroxy-4,8a-dimethyl-6-(1-methylethenyl)naphthalen-1( 2H )-one ( 26 ) [16], ent -4(15)-eudesmene-1 β ,6 α -diol ( 27 ) [32], methylsalicylate-2- O - β - d -glucopyranoside ( 28 ) [33], rozin ( 29 ) [19], piperchabaoside A ( 30 ) [20] (6 S ,9 R )-roseoside ( 31 ) [34], and 2′- O -methyluridine ( 32 ) [35], were identified by comparing their spectroscopic data with those in the literature.…”