This paper reports the isolation and structural elucidation of two minor products from Orthosphenia mexicana: orthosphenin [4], a new cassinic acid alkaloid sesquiterpene ester with an evoninol nucleus, and a new norisopimaradiene diterpene 8 of a type found only for the second time in the Celastraceae, where abietatriene diterpenes are the norm. © 1989, American Chemical Society. All rights reserved.