Sesquiterpene lactones. XXXIII. Guaianolides in the subgenus Psephellus (Cass.) Schmalh., genus Centaurea L.

Abstract

Sesquiterpene lactones were found to occur in all of the studied species of the subgenus <em>Psephellus</em> (Cass.) Schmalh. Differing compositions were found in the representatives of three sections. In <em>Centaurea declinata</em> MB. from the section <em>Leucophylle</em> (Sosn.) Sosn.. 15-deoxyrepin, linichlorin B and cynaropicrin were found. Linichlorin B dominated in <em>Centaurea hypoleucu</em> DC. from section <em>Hypoleucae</em> (Sosn.) Sosn., while in the species classified in section <em>Psephellus</em> Sosn., repin, acroptilin, jenerin, centaurepensin and, in some, also cynaropicrin. dominated.