Five new sulphur-containing amides from Glycosmis lucida with antifeedant activity against Tribolium castaneum

Five new sulphur-containing amides ( 2 , 5 – 8 ) and three known analogue compounds ( 1 , 3 – 4 ) were isolated from the leaves of Glycosmis lucida which were collected in Yunnan province, China. Their structures were elucidated with NMR spectroscopy and mass spectrometry. The compounds were identified as N -( p -hydroxyphenethyl)-3-(methylsulfonyl)-propenamide ( 1 ), N -[2-(4- hydroxyphenyl)-ethyl]-3-methanesulfonyl- N -methyl-propionamide ( 2 ), methylgerambullin ( 3 ), methylisogerambullone ( 4 ), methylgerambullindiol ( 5 ), N -{2-[4-(6,7-hydroxy-3,7-dimethyl-oct- 2-enyloxy)-phenyl]-ethyl}-3-methanesulfonyl- N -methyl-acrylamide ( 6 ), N -{2-[4-(6,7-dihydroxy- 3,7-dimethyl-oct-2-enyloxy)-phenyl]-ethyl}-3-methanesulfonyl- N -methyl-propionamide ( 7 ), ( E )- N -{2-[4-(6-hydroxy-7-dimethyl-oct-2-enyloxy)-phenyl]-ethyl}-3-methanesulfinyl- N -methyl- acrylamide ( 8 ). Feeding deterrent activities of these surphur-containing derivatives against Tribolium castaneum were assayed for the first time. Compound 2 , 3 , 6 possessed significant feeding deterrent activities against T. castaneum adults (EC 50   =   311.6, 244.9 and 108.3   ppm, respectively). These results demonstrated that some sulphur-containing amides are promising candidates as insect antifeedant agents.