Identification of the chemical constituents in the leaves and twigs of Nerium oleander by ultrahigh‐performance liquid chromatography coupled to quadrupole Orbitrap high‐resolution mass spectrometry

Nerium oleander L. (Apocynaceae) is a medium-sized evergreen flowering tree and is distributed widely in China. Various parts of N. oleander have been used medicinally and are reported to possess a wide range of biological activities, including cardiotonic, cytotoxic, and central nervous system depressant activities. However, there is a lack of in-depth understanding of the chemical constituents in various parts of N. oleander.