The synthesis and local anesthetic properties of five 1-dealkyloxindole-3-spiropyrrolidines and six 1-dealkyloxindole-3-spiropiperidines are described. The compounds studied include members of all five possible positional isomers of the two classes of spirooxindoles; all showed local anesthetic activity by the rat sciatic nerve block method. The coincidence of the least variability in the relative positions of basic nitrogen, amide carbonyl, and aromatic ring (compounds 1 and 6) with lowest normalized toxicity is noteworthy.

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A method for compliance analysis for total lysine in animal feed is described. One g portions of finely ground feed sample are spiked with a calculated amount of diaminobutyric acid internal standard and hydrolyzed by heating with 100 mL 6N aqueous HC1 at 120°C in a closed bottle. A very small aliquot (25 /*L) of hexane-washed hydrolysate is evaporated under vacuum to dryness and derivatized with dansyl chloride. Lysine is separated from other amino acids by isocratic reverse-phase (LC-18) liquid chromatography; the mobile phase is acetonitrile-O.OlM sodium phosphate (pH 7.0) buffer (100 + 210, v/v). The internal standard method along with a fluorescence detector (310-410 nm excitation and 435-650 nm emission), is used for quantitation. Thirty-five feed samples of various types (lysine 0.2- 8.2%) were analyzed with no interference from the matrix. The results were compared with those furnished by an independent laboratory using an amino acid analyzer; no statistical difference was found at the 95% confidence level. Six replicate analyses of a feed sample showed a coefficient of variation of 2.8%; no significant differences were found when between-day results of 9 samples (lysine 0.90- 4.30%) were compared. This procedure has been tested for ruggedness and can be applied for compliance determination of total lysine in feedstuffs by laboratories with limited resources

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