Extracts of the stem parts of the woody Composite Eremanthus elaeganus yielded lupeol acetate (1 ), friedelin (Z), epifriedelinol (3). a mixture of sitosterols, the flavonoids tamarixetin (3,5,7,3'-tetrahydroxy-4'-methoxyflavone), genkwanin (5,4'-dihydroxy-7-methoxyflavone),and luteolin 7-methyl ether (5,3',4'-trihydroxy-7-methoxyflavone), and the three novel modified germacranolides eremantholide A ( 5 ) . B (6), and C (minor component) ( 7 ) . The structures of eremantholides A and B were determined by X-ray crystallography, and a crystallographic comparison between the two structures is given. Eremantholide A reacts with propane-I -thiol by a novel 1.6-Michael-type addition which may simulate the mode of its cytotoxic action.

The alkaloid fraction of the Amazonian species Telitoxicum peruvianum (Menispermaceae) was found to contain the known alkaloids norrufescine (1), lysicamine (6), and subsesseline (2) as well as the new alkaloids telitoxine (3), peruvianine (4), and telazoline (7). Structures are proposed for the new alkaloids on the basis of spectroscopic data.As part of a continuing study of the alkaloids of the family Menispermaceae, we have investigated a number of plants of the South American genus Abuta (1-3). We now wish to report the isolation of some of the alkaloid constituents of Telitoxicum peruvianum, a species of the related and hitherto unexamined Amazonian genus Telitoxicum (4, 5).The total tertiary alkaloids were partitioned into phenolic and nonphenolic bases by extraction with 5% sodium hydroxide. The phenolic alkaloid fraction afforded, after separation by column chromatography on silica gel, the two known alkaloids, norrufescine (1) (1) and subsesseline (2) (6), and the two new alkaloids telitoxine (3) and peruvianine (4).•0 MeO 1 2 Telitoxine (3) was obtained as yellow flakes, mp 273-275°. Its high resolution mass spectrum indicated the molecular composition C17H13NO3. The ultraviolet spectrum of telitoxine was similar to that of the azafluoranthene alkaloid, norrufescine. Its nmr spectrum revealed a substitution pattern slightly different from that of norrufescine. The singlet at 7.18 was assigned to the C-3 proton; the remainder of the spectrum consisted of two methoxyls ( 4.06 and 4.07), a pair of doublets (2 H, 6 Hz) at 8.50 and at 7.53, doublets at 7.82 (1 H, 7 = 9 Hz) and at 7.57 (1 H, 7 = 2 Hz), and a quartet at 6.92 (1 H, 7 = 9 Hz and 2 Hz). The small ortho coupling constant of 6 Hz is consistent with the assignment of the 8.50 and 7.53 signals to pyridine ring protons at C-2 and C-3, respectively. Based on spectral evidence, structure (3) was assigned to telitoxine, making it a hydroxy derivative of triclisine (5) isolated from Triclisia gilletti (Dewild) Staner (7).Peruvianine (4) crystallized from methanol as red orange prisms, mp 252-255°3 20

The caryophyllene derivative lychnophoric acid (2) and several eremantholides have been isolated from the cytotoxic extracts of L. affinis as well as two germacranolides, lychnophorolides A and B, having both «-methylene 7-lactone and 3(2fl)-furanone electrophilic functions. The structure of lychnophorolide A has been shown to be 3 by X-ray analysis, and lychnophorolide B is assigned structure 4. Comparison of bond lengths and angles from the crystal structure determination of lychnophorolide A and the previously determined eremantholides A and B shows a remarkable conformational similarity in the cyclodecadienone rings of these compounds.

Irradiation of If in Methanol. A solution of If (200 mg) in methanol (30 mL) was photolyzed and worked up in the usual way to afford oxindole 11 (mp 99-101 °C), ester 12, and aceto-

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