Two new thiazoyl substituted indole phytoalexins, camalexin (5) and methoxycamalexin (8), were Isolated from Camelina sativa leaves following elicitation by the fungus Altenmia brassme. The phytoalexin theory of disease resistance in plants, fist proposed by Miiller and Biirgerl, explams many plant-pathogen interactions. Recently, we and others have demonstrated that plants of the farmly Cruclferae accumulate phytoalexins after exposure to microorganisms. These compounds are of special interest since they were the first phytoalexins reported to contain sulfur. When Pseudomonas cichorij (Swingle) Stapp was used as an elicitor, the Chinese cabbage (Brassica campestris L. ssp. pekinensis) produced brassinin (1) and cyclobrassinin (2)2, and the Japanese vegetable, daikon (Rbaphanus sativus L. var. hortensw), produced splrobrassinin (3)3. On the other hand, the mustard plant (B. juncea (L.) Cosson) showed resistance to the blackleg fungus Leptosphaeria maculans @esm.)Ces. et de Not. and this phenomenon was shown fo he due to the synthesis and accumulation of brassilexin (4)4 after infection. Recently Conn et ap have shown that leaves of false flax (Camelina sativa (L.) Crantz) were resistant to AItemaria brassicae (Berk.) Sacc., the causal agent of blackspot disease of rapes&,, and this resistance was attributed to the production of unidentified phytoalexins Tlus paper describes the isolation, separation, and structure elucidation of the major component produced by C sativa which is fungitoxic to A. brassicad.