Determination of Diclazuril in Avian Feed and Premixes with Gas Chromatography/Mass Spectrometry

A method is presented for the determination of the relatively new anticoccidial drug diclazuril in avian feed and premixes. The drug was extracted from feed with acidified methanol-water, and the extracts were cleaned up by simple liquid-liquid extraction. These were then derivatized with ethereal diazomethane, and the methyl derivatives were analyzed by gas chromatography/mass spectrometry on a bench-top instrument An internal standard was used to enhance the reproducibility and ruggedness of the assay. The coefficients of variation for a finished feed and premix assayed 5 times each on 3 occasions were 6.6 and 6.0%, respectively. The detection limit of the assay is about 0.02 mg/kg, which is adequate for measuring the normal inclusion rate of 1 mg/kg in finished feed.

Metabolites produced by the Scleroderris canker fungus, Gremmeniellaabietina. Part 3. Some further metabolites

This article describes the metabolites of a strain of Gremmeniellaabietina (Lagerb.) Morelet indigenous to Alberta. This strain does not produce the phenalenone derived metabolites isolated from the other strains of G. abietina examined to date. Only fatty acids and esters, glycerides, and sterol esters were produced. This raises a question regarding the identity of this particular strain. A greenish-yellow metabolite named Scleroderris green, isolated from a New Brunswick strain of G. abietina, is shown to have structure 12. Scleroderris green (12) is structurally related to Scleroderris blue (4) and is produced when the latter compound is reduced with sodium bisulfite. Air oxidation of Scleroderris green (12) gives rise to Scleroderris blue (4). The structure of compound 12 was established by a study of the 13C nmr spectra of the three pentamethyl derivatives (8, 9, and 10) produced when 12 is treated with ethereal diazomethane. It is suggested that the greenish discoloration of the wood of Scleroderris infected pine may be due to the presence of compound 12.

Safe Storage Vessel for Small Quantities of Diazomethane

Two relatively safe, inexpensive, and easily fabricated vessels for the storage of small quantities of ethereal diazomethane are described

Reactions with 4-Thiohydantoin. Preparation of 5-Arylidene-4-Thiohydantoin, their Reactions towards Grignard Reagents and the Alkylating Agents

4-Thiohydantoin and 1-phenyl-4-thiohydantoin reacted with aromatic aldehydes to give the corresponding 5-arylidene-4-thiohydantoin (1 a-h). la was obtained also from 5-benzylidene hydantoin and phosphorous pentasulphide. Grignard reagents added to the lateral double bond of (1 a-c) to give after hydrolysis the colorless products 3. Treatment of (1a, b) with alkylating agents gave the corresponding alkylmercapto derivatives (4 a-h). Also (4a, e) were obtained by the action of ethereal diazomethane on (1a, b). By further methylation of (4 e) with diazomethane, a cyclopropane derivative could be isolated.

Preparation of Methyl Derivatives of Some Organic Acids for Analysis by Gas–Liquid Chromatography

One microgram to 1 mg of organic acid was completely converted to its methyl derivative when it was dissolved in methanol and treated with an excess of ethereal diazomethane. Single products were obtained from α-ketoglutaric acid, oxaloacetic acid, pyruvic acid, glyoxylic acid, or hydroxypyruvic acid on reaction with thionyl chloride – methanol. The separation of 24 organic acids by gas–liquid chromatography on a Reoplex 400 column is presented.