The new norsesquiterpene hydrocarbon, cyprotene, the sesquiterpenes 2,4-patchouladiene, epoxycyperene, 2,4,11 -eudesmatriene and 3,5,11 -eudesmatriene, were identified as constituents in the hydrodistillation products of Cyperus alopecuroides from Cameroon by spectroscopic methods and chemical conversions.