A triangulane is a hydrocarbon consisting exclusively of a series of spiro-linked cyclopropane rings.
Triangulanes are named according to the rules of systematic nomenclature for spiro compounds. The pattern of their common names is "[n]triangulane", where n is the number of cyclopropane units. The simplest such chemical, triangulane, is named spiro[2.2]pentane by systematic nomenclature. Chains consisting of four or more cyclopropane units—triangulane and higher—can form chiral helices. This property is unusual for a molecule that contains no stereogenic atoms; the chiral nature is due to restricted mobility of the chain ends analogous to helicene molecules.
The rings can form a branched or cyclic patterns. For example, rotane is a branched triangulane; it consists of one additional cyclopropane attached to the central ring of a triangulane chain.
Triangulane derivatives have seen some use in medicine — e.g. lomedeucitinib contains a triangulane ring system, while vanzacaftor contains a triangulane ring system.
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