A new pyrrolidine alkaloid, acanthophoraine A (1), along with six known alkaloids (2-7), had been isolated from the red alga Acanthophora spicifera. The structures of these compounds were identified by spectroscopic analyses. The absolute configuration of 1 was established by ECD calculation. Compound 1 represents the first example of N-isobutyl pyrrolidone with an urea arm. The antimicrobial activity of 1 was also evaluated.[Figure: see text].
Keywords: Acanthophora spicifera; Red alga; alkaloids.