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The polar parts of the title plant gave several lignans including six new ones named vladinol A-F. The structures were elucidated by high field (1)H-NMR spectroscopy and a few chemical reactions. The stereochemistry was determined by the observed NOE's and by comparison of the (1)H-NMR data with those of related lignans.

The polar fractions of the extract of the aerial parts of CALENDULA PERSICA afforded eight sesquiterpene glycosides, five derived from viridiflorol, two of beta-eudesmol, and one of 4alpha-hydroxygermacra-1(10) E,5E-diene. In addition to fucopyranosides, also chinovopyranosides were present. The structures were elucidated by high field NMR techniques.

Isolation from Calea prunifolia of sesquiterpenes derived from acorane, daucane, and a new type of alicyclic sesquiterpene carbon skeleton, caleprunane, is described. Furthermore, two benzofurans were isolated. The structures were elucidated by spectroscopic methods.From the large genus Calea (Compositae, tribe Heliantheae, subtribe Neurolaeninae) several species have already been investigated chemically. Most species contain highly oxygenated sesquiterpene lactones (1). Having studied the constituents of a species from Costa Rica, Calea prunifolia H.B.K., we now report the results in this paper.The aerial parts afforded a complex mixture of hydrocarbons that could be separated by AgNOj-coated silica columns and plates. In addition to a-and ß-farnesene, germacrene D, caryophyllene, and dauca-2,11-diene (2), three other hydrocarbons, the 2 8 15

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A reinvestigation of the aerial parts of Heliopsis buphthalmoides gave in addition to compounds isolated previously four new lignans and two unsaturated amides. Some time ago we isolated some lignans (1, 2) from Heliopsis buphtalmoides. As these compounds show remarkable biological activities (3) we have reinvestigated the aerial parts of the same species which were collected in Peru. While the unpolar fractions afforded a-and 3-farnesene, germacrene D, caryophyllene and phytol the more polar fractions gave seven lignan derivatives (1-7) only three of them being isolated previously, (1) (1), heliobuphthalmin (2) (1) and 4(2). Five highly unsaturated isobutylamides were also obtained, the enynes 8(1,4) and 9, the enyne dienes 10and 11(1) as well as the ynediene 1.2.The structure of 3, molecular formula C22H2209, followed from the 1H NMR spectrum (Table I) which clearly showed that we were dealing with a biscarbomethoxy derivative (8 3.68 and 3.53 s) with two trisubstituted aromatic moieties. A four proton singlet at 8 = 5.93 indicated the presence ot two dioxymethylene groups. However, in contrast to the spectrum of 2, the aromatic signals showed that this compound was not symmetric. Accordingly, the signals of the benzylic protons showed different splitting, one pair of doublets and one pair of double doublets. A broadened singlet at 8 = 3.58 indicated a hydroxy group which could only be placed at C-8. Its presence also followed from the IR spectrum, which further indicated a

The aerial parts of VERBESINA PERSICIFOLIA DC afforded a new eudesmane derivative in addition to known compounds. The roots of V. SUBCORDATA gave also new eudesmane cinnamates in addition to several known ones as well as a 5alpha-hydroxybicyclogermacra-1 (10) E, 4 (15)-diene. A reinvestigation of V. VIRGINICA L. gave two new ( Z)-configurated coumarates. Furthermore the structures of some sesquiterpenes are revised. The structures were elucidated by highfield NMR spectroscopy and a few chemical reactions.

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