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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%.

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.