The 13C NMR spectra of the aconitine-type diterpenoid alkaloids aconitine, mesaconitine, deoxyaconitine, delphinine, chasmanine, delphisine, neoline, condelphine, isotalatizidine, as well as 17 related derivatives, have been obtained by the Fourier transform technique at 25.03 MHz. The signal due to each carbon atom has been assigned, and some previously published assignments in the alkamine, delphonine, and the alkaloid, isotalatizidine, are corrected. The spectra are analyzed in terms of substituent effects. On the basis of chemical correlation of chasmanine-neoline-delphisine, and similar values for the resonances in the 13C spectra of chasmanine, deoxyaconitine, delphinine, and delphonine, especially in the case of the ring A carbons, the configuration for the methoxyl at C-l in chasmanine has been revised to an «-equatorial methoxyl group. The results of a study of the "pyrodelphonine chromophore" in the electronic ground state of the molecule, using 13C and NMR techniques, are presented.

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The ethanolic extract of sage {Salvia officinalis L.} was separated into five fractions through reextraction with supercritical CO2. Further fractionation of the most active antioxidant fractions by means of liquid chromatography, with silicic acid as absorbent, yielded 2H-10,4a-(epoxy methano}-phenantren-12-one-l,3,4,9,10,10ahexahydro-5,6-dihydroxy-9a-ethoxy-1,1-dimethyl-7-(1methylethyl), (rosmanol-9-ethyl ether}. The same compound was isolated from the alcoholic extract of the hyssop {Hyssopus officinalis L.}. Rosmanol-9-ethyl ether was shown to be one of the active antioxidant components in sage and hyssop, with activity much greater than butylated hydroxytoluene (BHT}. KEY WORDS: Hyssop extract, natural antioxidants, rosmanol-9-ethyl ether, sage extract, supercritical CO 2 extraction. Natural products, isolated from spices, can act as antioxidants either alone or synergistically with chemical additives. In 1977, Chang et al. (1} reported a patented

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This paper reports a simple method of degradation of the readily available labdane group of diterpenoids to drimanic sesquiterpenes. The synthesis of (+)-drimane-8,11 -diol (5), the (+) and (±) forms of 14,15-bisnor-8a-hydroxylabd-11 (E) -en-13-one ( 7), (±)-8-epimeric hydroxy ,/3-unsaturated ketone (12), and (-)-drimenol (8) is described. Treatment of (+)-ambreinolide (1) with Pb(OAc)4 in boiling benzene for 120 hr gave compounds 2 (12%), 3 (22%), and 4 27%). Treatment of 1 with DDQ in boiling p-dioxane for 48 hr afforded 2 (40%). Ozonolysis of 2 in methylene chloride at -70°, followed by treatment with Red-Al, gave (+)-5 (85%). Oxidation of the latter with CrOg-pyridine gave aldehyde (+)-6 (50%). Treatment of (+)-6 with sodium diethyl 2-oxopropylphosphonate in THE gave (+)-7 (40%). A parallel series of reactions starting with (±)-ambreinolide ( 1) gave (±)-2, (±)-5, (±)-6, and (±)-7. Treatment of (+)-5 with AC2O overnight gave a monoacetate which was dehydrated with POClg-pyridine at 0-5°to give a mixture of isomeric acetates. Basic hydrolysis of the latter gave a mixture of alcohols 8 and 9. From this mixture (-)-dimenol (8) was isolated by preparative TLC. Treatment of (i)-drimenol (8) with mchloroperbenzoic acid in methylene chloride at 0-5°g ave a mixture of a and ß epoxides. Reduction of the ß epoxide with L1AIH4 in THE gave diol 10. Oxidation of 10 with CrOg-pyridine gave 11, which on treatment with sodium diethyl 2-oxopropylphosphonate in THE gave ketone 12 (30%).