<jats:title>Abstract</jats:title><jats:p>From the aerial parts of <jats:italic>Senecio dianthus</jats:italic>, four new eremophilenolides (<jats:bold>1</jats:bold>–<jats:bold>4</jats:bold>, resp.) and one new eremophilenolide alkaloid (<jats:bold>5</jats:bold>), of the relatively uncommon eremophilenoid‐type sesquiterpenoid lactones, were isolated together with three known sesquiterpenoid lactones, 10<jats:italic>β</jats:italic>‐hydroxyeremophil‐7(11)‐en‐12,8<jats:italic>α</jats:italic>‐olide (<jats:bold>6</jats:bold>), 8<jats:italic>β</jats:italic>,10<jats:italic>β</jats:italic>‐dihydroxyeremophil‐7(11)‐en‐12,8<jats:italic>α</jats:italic>‐olide (<jats:bold>7</jats:bold>), and 10<jats:italic>α</jats:italic>‐hydroxy‐1‐oxoeremophila‐7(11),8(9)‐dien‐12,8‐olide (<jats:bold>8</jats:bold>). On the basis of IR, MS, and NMR data, particularly 2D‐NMR analyses, the structures of the new compounds were established as: 2<jats:italic>β</jats:italic>‐(angeloyloxy)‐10<jats:italic>β</jats:italic>‐hydroxyeremophil‐7(11)‐en‐12,8<jats:italic>α</jats:italic>‐olide (<jats:bold>1</jats:bold>), 6<jats:italic>β</jats:italic>‐(angeloyloxy)‐10<jats:italic>β</jats:italic>‐hydroxyeremophil‐7(11)‐en‐12,8<jats:italic>α</jats:italic>‐olide (<jats:bold>2</jats:bold>), 2<jats:italic>β</jats:italic>‐(angeloyloxy)‐8<jats:italic>β</jats:italic>,10<jats:italic>β</jats:italic>‐dihydroxyeremophil‐7(11)‐en‐12,8<jats:italic>α</jats:italic>‐olide (<jats:bold>3</jats:bold>), 2<jats:italic>β</jats:italic>‐(angeloyloxy)‐8<jats:italic>α</jats:italic>‐hydroxyeremophila‐7(11),9(10)‐dien‐12,8<jats:italic>β</jats:italic>‐olide (<jats:bold>4</jats:bold>), and 8<jats:italic>β</jats:italic>‐amino‐10<jats:italic>β</jats:italic>‐hydroxyeremophil‐7(11)‐en‐12,8<jats:italic>α</jats:italic>‐olide (<jats:bold>5</jats:bold>). In addition, the relative configuration of <jats:bold>1</jats:bold> was corroborated by X‐ray diffraction analysis.