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Xylopien [1] and xylomatenin [2], two new bioactive monotetrahydrofuran Annonaceous acetogenins, have been isolated from an EtOH extract of the bark of Xylopia aromatica, using bioactivity-directed fractionation employing lethality to brine shrimp. These new compounds each have a double bond in the hydrocarbon chain and have been identified as C-23, C-24 dehydro analogs of xylopiacin and xylomaticin. Their structures were elucidated by spectral analyses of the parent compounds and/or simple chemical derivatives. Their absolute stereochemistries have been established by 1H- and 2D nmr experiments utilizing the production of Mosher esters. These acetogenins showed cytotoxic potencies superior to adriamycin against three human solid tumor cell lines.

By guiding fractionation with brine shrimp lethality, three novel compounds, with cytotoxic activities against human tumor cell lines, have been isolated from the bark of Melodorum fruticosum Lour.(Annonaccae). These compounds have benzoyl moieties in common with a c7 dienone or lactone terminal which appears to arise from a heptose or the equivalents. They were named melodienone, isomelodienone, and acetylmelodorinol.

A precise and selective high-performance liquid chromatographic (HPLC) method with diode-array detection for quantifying huperzine A in formulated products was developed and validated. A liquid chromatographic-mass spectrometric (LC/MS) procedure was devised to confirm the HPLC method. Huperzine A was dissolved in 1,2-dichloroethane, chromatographed on a YMCBasic C18 column, and detected at 308 nm. A gradient mobile phase of 10 mM ammonium acetate (pH = 3.5)--methanol was used. Identification was based on retention time, UV spectra and mass spectra by comparison with a commercial standard. The UV peak areas were used for quantitation of huperzine A content. The correlation coefficient (R2) of the calibration curve was 1 over the range 0.8-11.6 microg/ml. Overall recovery of huperzine A was 103.9% +/- 1.8 (mean +/- SD). Relative standard deviations for intra- and interday precision were < 2%.

The cactus genus Coryphantha has been reported to contain certain β-phenethylamine alkaloids. In this investigation, a Texas species, C. ramillosa Cutak, yielded five alkaloids which were isolated chromatographically and crystallized as their hydro-chloride salts. The isolated compounds were identified as N-methyl-4-methoxy-β-phenethylamine hydrochloride, hordenine hydrochloride, N-methyltyramine hydrochloride, synephrine hydrochloride, and β-O-methylsynephrine hydrochloride, all of which have been previously identified in other Coryphantha species.

A technique for qualitative identification and quantitative determination of micro quantities of ergot alkaloids has been developed. Using glass plates spread with a layer of silica gel G and a solvent system composed of benzene:dimethylformamide (13:2) or of ethyl acetate:dimethylformamide:ethanol (13:1.9:0.1), one can separate ergonovine, ergotamine, ergosine, ergocristine, and a mixed zone composed of ergocornine and ergokryptine. The mixed zone is removed from the plate, the alkaloids eluted with 10 per cent methanol in chloroform, and filtered or centrifuged to remove the silica gel. The eluant is evaporated, and the mixture of the alkaloids is dissolved in a standard volume of methanol-chloroform. The respotting of this solution on glass plates spread with a layer of aluminum oxide G and chromatographed with a solvent system composed of chloroform:ether:water (3:1:1) results in the separation of ergocornine and ergokryptine. These solvent systems can be utilized to separate the isomers of the six alkaloids with equal facility. The technique has been extended to the resolution and quantitative estimation of the alkaloids.

The presence of alkaloids was chromatographically demonstrated in seven species of Coryphantha. By using preparative chromatographic techniques, N-methyl-3,4-dimethoxy-β-phenethylamine, N-methyl-4-methoxy-β-phenethylamine, N-methyltyramine, and N,N-dimethyltyramine (hordenine) were isolated from extracts of C. cornifera (DC.) Br. and R. var. echinus (Engelm.) L. Benson. In addition, two new cactus alkaloids, N-methyl-4-hydroxy-β-methoxy-β-phenethylamine (β-O-methylsynephrine) and 4-methoxy-β-hydroxy-β-phenethylamine, were identified spectroscopically in extracts of this species.

Although contact dermatitis from shoes is common, the causative allergen is frequently not known. Reliance cannot be placed on standard screening trays because such testing can be negative when testing to shoe materials is positive. Furthermore, the relevance of positive screening tests is almost never proven by extracting that allergen from the patient's shoes. We present a case of insole dermatitis to tennis shoes in which we directly isolated the causative allergens by step-by-step patch-test monitoring of active fractions. Chromatographic separation of the active fractions led to the isolation of 2 allergens, mereaptobenzothiazole (Captex) (MBT) and its dimmer, dibenzothiazyl disulfide (Altax) (DBTD). Patch tests to DBTD were noticeably more potent than those to MBT. In what might be considered an obvious case of contact sensitivity to MBT, the actual allergen isw DBTD. Using this method, unknown shoe allergens can be isolated, identified, and added to the shoe test tray of potential fallergens.

Hordenine HCl and N-methyltyramine HCl were crystallized from extracts of the cactus Ariocarpus kotschoubeyanus (Lemaire) Schumann. Other alkaloids, which have been found in closely related Ariocarpus species, were not detected in this species. Extraction of the isolated alkaloids by percolation gave higher yields than continuous extraction.

Eleven β-phenethylamine derivatives were isolated and identified from fresh-frozen specimens of Coryphantha macromeris var. runyonii (Br. and R.) L. Benson. Isolations were accomplished using preparative TLC, and identifications were based on chromato-graphic properties, IR and NMR spectra, and comparisons with authentic materials. The data provide initial documentation for: the occurrence of N-formylnormacromerine in nature; the first recorded detection of metanephrine and N-methylmetanephrine in the plant kingdom; the first occurrence of synephrine and N-methyltyramine in this cactus; confirmation of earlier GLC-mass spectral data on the presence of N-methyl-4-methoxy-β-phenethyl-amine, N-methyl-3,4-dimethoxy-β-phenethylamine, tyramine, and hordenine in the plant; and verification of previous reports on the isolation of macromerine and normacromerine.

Macromerine, a β -phenethylamine alkaloid previously isolated from Coryphantha macromeris , has been isolated from Coryphantha runyonti .

Ariocarpus fissuratus var. fissuratus (Engelmann) K. Schumann, commonly known as living rock, chaute, peyote, sunami, or dry whiskey, has an interesting history of folkloric medicinal uses. In previous phytochemical studies the alkaloids, hordenine and N-methyltyramine, have been identified in both the fissuratus and lloydii varieties of the species. In the present investigation, a new alkaloid was crystallized from the nonphenolic alkaloid fractions and identified as N-methyl-3,4-dimethoxy-β-phenethylamine HCl. This compound has previously been reported in three other cactus species.