Zanthoxylum (including Z. fagara) is a genus of about 250 species of deciduous and evergreen trees and shrubs in the citrus or rue family, Rutaceae, native to warm temperate and subtropical areas worldwide. Common names include Prickly-ash and Hercules' Club.

The fruit of several species are used to make the spice Sichuan pepper. They are also used as bonsai trees. Historically, the bark was widely used for toothache, colic, and rheumatism.

Zanthoxylum nitidum is commercially used in healthcare products for the improvement of tooth condition. Its fruit is also used as a spice. Three new benzenoids, (E)-4-(4-hydroxy-3-methylbut-2-enyloxy)benzaldehyde (1), (E)-methyl 3-(4-((E)-4-hydroxy-3-methylbut-2-enyloxy)phenyl)acrylate (2), and (Z)-methyl 3-(4-((E)-4-hydroxy-3-methylbut-2-enyloxy)phenyl)acrylate (3), have been isolated from the stem wood of Z. nitidum, together with 17 known compounds (4–20).