Isolation and structure elucidation of the new fungal metabolite (-)-xylariamide A.
Chemical investigations of the terrestrial microfungus Xylaria sp. have afforded the new natural product (-)-xylariamide A (1). The gross structure of 1 was determined by interpretation of 1D and 2D NMR, UV, IR, and MS data. Confirmation of the structure and the absolute stereochemistry of 1 were determined by the total synthesis of (+)-xylariamide A (2). Synthetic 2 was produced by N,O-bis(trimethylsilyl)acetamide-induced coupling of 3-chloro-L-tyrosine (3) with (E)-but-2-enedioic acid 2,5-dioxo-pyrrolidin-1-yl ester methyl ester (4). Optical rotation comparison of 1 with 2 indicated that the natural product (1) contained 3-chloro-D-tyrosine. Both enantiomers of xylariamide A were tested in a brine shrimp lethality assay, and only the natural product (1) showed toxicity.
Davis
Rohan A
RA
Chemical Biology Program, Eskitis Institute, Griffith University, Brisbane, QLD 4111, Australia. r.davis@griffith.edu.au
D000818:Animals; D001156:Artemia / Q000187:drug effects; D001203:Ascomycota / Q000737:chemistry*; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D013237:Stereoisomerism; D014443:Tyrosine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification* / Q000494:pharmacology
C501799:xylariamide A; D014443:Tyrosine; C087259:3-chlorotyrosine