Alpha-Amyrone (Alfa-Amyrenone) is a natural poduct found in aerial parts of Inula candida (L.) Cass. subsp. Alpha-Amyrone is an antineoplastic agent.

Taccalonolide AJ is a microtubule stabilizer; it has excellent and highly persistent antitumor efficacy when administered directly to the tumor, suggesting that the lack of antitumor efficacy seen with systemic administration of AJ is likely due to its short half-life in vivo.

Negsehisandrin G is a natural product.