Echinopsacetylenes A and B, New Thiophenes from Echinops transiliensis

Two new polyacetylene thiophenes, echinopsacetylenes A and B (1 and 2), were Isolated from the roots of Echinops transiliensis. The structures of 1 and 2 were elucidated on the basis of spectroscopic analyses and chemical transformations. Echinopsacetylenes A (1) Is the first natural product possessing an cc-terthienyl moiety covalently linked with another thiophene moiety. Echinopsacetylenes 8 (2) is the first natural thiophene conjugated with a fatty acid moiety. Echinopsacetylene A (1) showed toxicity against the Formosoan subterranean termite (Coptotermes formosanus).