苉（Picene）是一种多环芳香烃，化学式C₂₂H₁₄，由泥炭焦油或石油蒸馏的残留物蒸馏至干，用对异丙基甲苯反复重结晶得到。

苉为具有蓝色荧光的无色晶体，溶于浓硫酸溶液显绿色。在冰醋酸溶剂中用铬酸氧化苉得到苉醌，随着氧化继续进行稠环断裂形成羧酸，最终产物为邻苯二甲酸。苉晶体层间掺入钾或铷冷至18K以下时体现出超导性。.

Picene is a hydrocarbon found in the pitchy residue obtained in the distillation of peat tar and of petroleum. This is distilled to dryness and the distillate repeatedly recrystallized from cymene. It may be synthetically prepared by the action of anhydrous aluminium chloride on a mixture of naphthalene and 1,2-dibromoethane, or by distilling a-dinaphthostilbene. It crystallizes in large colorless plates which possess a blue fluorescence. It is soluble in concentrated sulfuric acid with a green color. Chromic acid in glacial acetic acid solution oxidizes it to picene-quinone, picene-quinone carboxylic acid, and finally to phthalic acid.