Cis-avicennol,a new pyranocoumarin from the root bark of Zanthoxylum elephantiasis

A new pyranocoumarin has been isolated from the root bark of Zanthoxylum elephantiasis and identified as cis-avicennol (6-(3-hydroxy-3-methyl-cis-but-1-enyl)-5-methoxy-2,2-dimethyl- 2H-benzo [1,2b:3,4b′] dipyran-8-one) on the basis of comparison of spectral data with that of trans-avicennol and conversion to tetrahydroavicennol. The usefulness of the lanthanide shift reagent Eu(fod)₃ in the assignment of cis configuration to the butenyl sidechain is briefly discussed.     

A pyranocoumarin from Atalantia ceylanica

Ceylantin, assigned the structure 7,8-dimethoxy-5,6-pyranocoumarin, and xanthotoxin have been isolated from the heartwood of Atalantia ceylanica.     

Alkaloids of Zanthoxylum monophyllum and Z. punctatum

The known alkaloids N-methylcorydine and magnoflorine were major constituents of stems and branches of Zanthoxylum punctatum (Rutaceae). Berberine was the major alkaloid of Z. monophyllum, which also contained a new pyrano-2-quinolone alkaloid, zanthophylline, and its desmethyl analog. Zanthophylline has an —NCH₂OAc functional group which is readily hydrolyzed by dilute acid. Methyl vanillate and the furocoumarin columbianetin were also found in Z. monophyllum.     

Isofraxinellone,a limonoid lactone from the bark of Fagaropsis glabra

Two lactones, both degraded limonoids, have been isolated from the trunk bark of Fagaropsis glabra. Isofraxinellone is a new natural compound and fraxinellone has previously been characterized in plants of the same family. The structure of isofraxinellone was determined by physical and chemical methods.     

An acridone alkaloid from the root bark of Atalantia monophylla

Atalaphylline 3,5-dimethyl ether, a new acridone alkaloid from Atalantia monophylla, has been characterized on the basis of spectral data and chemical transformations.     

Flavonoids from Elaeodendron balae root bark

The root bark of Elaeodendron balae afforded ourateacatechin, ouratea-proanthocyanidin A and a new leucoanthocyanidin derivative elaeocyanidin.     

Muellitol,a novel trialkenyl inositol from Evodiella muelleri

Muellitol has been isolated from the leaves of Evodiella muelleri and the structure established as 1,3,5-tri-(3-methyl-2-butenyl)cyclohexane-r-1-t-2-c-3-t-4-c-5-t-6-hexol. Chemical and spectroscopic examination of the compound and its derivatives showed it to be conformationally similar to scyllitol. This is the first report of the natural occurrence of a triprenylinositol.     

N-methylflindersine from Spathelia sorbifolia

The isolation and taxonomic significance of N-methylflindersine from S. sorbifolia is discussed.     

Magnolialide: A novel eudesmanolide from the root bark of Magnolia grandiflora

The hitherto unknown γ-isomer of the two eudasmanolides santamarine and reynosin was found to occur naturally in the root bark of M. grandiflora L. Its identity was established by studying its spectral data and by synthesis by cyclizing costunolide-1,10-epoxide. It was named magnolialide.     

New coumarins from Coleonema album

Six coumarins have been isolated from the aerial parts of Coleonema album and identified as ulopterol, 7-(3′, 3′-dimethylallyloxy)-coumarin, (R)-(+)-2′,3′-epoxy-suberosin, and the novel coumarins (R)-(+)-7-(2′, 3′-epoxy-3′-methylbutoxy)-coumarin, (R)-(+)-7-(2′,3′-dihydroxy-3′-dihydroxy-3′-methylbutoxy)-coumarin and (R)-(+)-7-methoxy-8-(2′,3′-epoxy-3′-methylbutoxy)-coumarin.     

7-Phenylacetoxy coumarin from limonia crenulata

A new coumarin, 7-phenylacetoxycoumarin, has been isolated from Limonia crenulata along with luvangetin, xanthotoxin, umbelliferone and limonin. This is the first report of a coumarin phenol ester from a natural source.     

Alkaloids of Rauwolfia nitida root bark

Thirty-three indole alkaloids were isolated from the root bark of Rauwolfia nitida. Sarpagan, dihydroindole, indolenine, yohimbine, 18-hydroxy-yohimbine ester, heteroyohimbine and anhydronium base types were isolated. The principal alkaloids were reserpine (0.034%), serpentinine (0.033%), pseudoreserpine (0.013%) and reserpiline (0.012%).