Two alkaloids have been isolated from the Chinese drug, Ching-feng-terng, Sinornenium acutum Rehd.et Wils., collected in Yi-shing district of Kiangsu province.One of them was identified to be sinomenine by comparison of its UV spectrum as well as physical constants of its salts with those of sinomenine.The other alkaloid seems to be a new one, having the empirical formula C₁₉H₂₁O₄N, m.p.198°, [α]_D³²-81.6° (chloroform), and was named sinoacutine.It is a tertiary base, containing one phenolic hydroxyl, one carbonyl and two methoxyl groups.The following crystalline salts and derivatives have been prepared:perchlorate, m.p.177°;picrate, m.p.222° (decomp.); tartrate, m.p.203-204°;methiodide, m.p.216°;oxime, m.p.223°;and sinoacutinol, m.p.226°.