The phytoalexins from cauliflower, caulilexins A, B and C: Isolation, structure determination, syntheses and antifungal activity

• Published in: Phytochemistry (Oxford) 2006-07, Vol.67 (14), p.1503-1509
• Main Authors: Pedras, M. Soledade C., Sarwar, Mohammed G., Suchy, Mojmir, Adio, Adewale M.
• Format: Article
• Language: English
• Subjects: 1-Methoxyindolyl-3-acetonitrile; Antifungal Agents - chemical synthesis; Antifungal Agents - chemistry; Antifungal Agents - isolation & purification; Antifungal Agents - pharmacology; antifungal properties; Ascomycota - drug effects; Biological and medical sciences; Botrytis; Brassica; Brassica - chemistry; Brassica oleracea; Brassica oleracea var. botrytis; Brassicaceae; Brassicanal C synthesis; Brassitin; Cauliflower; caulilexins; Chemical constitution; Chemical control; chemical structure; Control; Crucifer; Cruciferae; Fundamental and applied biological sciences. Psychology; Fungal plant pathogens; Indoles - chemical synthesis; Indoles - chemistry; Indoles - isolation & purification; Indoles - pharmacology; Leptosphaeria maculans; Leptospira - drug effects; Microbial Sensitivity Tests; Molecular Structure; Phoma lingam; Phytoalexin; phytoalexins; Phytopathology. Animal pests. Plant and forest protection; plant pathogenic fungi; Plant physiology and development; Rhizoctonia - drug effects; Rhizoctonia solani; Sclerotinia sclerotiorum; Sesquiterpenes; spectral analysis; Spirobrassinin; Terpenes - chemical synthesis; Terpenes - chemistry; Terpenes - isolation & purification; Terpenes - pharmacology; Thanatephorus cucumeris
• ISSN: 0031-9422; 1873-3700
• DOI: 10.1016/j.phytochem.2006.05.020

Investigation of phytoalexin production in cauliflower led to isolation of seven phytoalexins, three of which are new; syntheses and antifungal activities are reported. Our continuous search for phytoalexins from crucifers led us to examine phytoalexin production in florets of cauliflower ( Brassica oleracea var. botrytis) under abiotic (UV light) elicitation. Four known (isalexin, S-(−)-spirobrassinin, 1-methoxybrassitin, brassicanal C) and three new (caulilexins A–C) phytoalexins were isolated. The syntheses and antifungal activity of caulilexins A–C against the economically important pathogenic fungi Leptosphaeria maculans, Rhizoctonia solani and Sclerotinia sclerotiorum, and the first synthesis of brassicanal C are reported.