1 The effects of 8-oxoberberine (JKL1073A) on contractions and electrophysiological characteristics of atrial tissues were examined.2 In driven left atria of the rat JKL1073A (10-100 gM) increased twitch tension dose-dependently. In spontaneously beating right atria, JKLI073A increased twitch tension but decreased beating rate slightly. 3 The positive inotropic and the negative chronotropic effect of 30 gM JKLI073A was not affected by prazosin (1 gM), propranolol (1 gM) and 3-isobutyl-1-methyl-xanthine (10 Mm) but significantly suppressed by 4-aminopyridine (2 mM 4-AP). 4 Current-clamp study revealed that JKL1073A prolonged rat atrial action potential duration (APD). This prolongation of APD by JKL1073A was decreased by pretreating the cells with 2 mM 4-AP.Voltage-clamp study showed that JKL1073A inhibited the integral of the transient outward current (It.)

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Enantiomers of β‐lactams bearing aryl, furyl or styryl substituents in the 4‐position were chromatographically separated by means of high‐performance liquid chromatography on chiral column packed with amino acid‐derived chiral stationary phase. Separation factors are generally modest. To improve further the resolution of enantiomers, the rings of these β‐lactams were opened with octanol in acidic conditions and converted into N‐3,5‐ dinitrobenzoyl ester derivatives of the resulting β‐amino acids. Enantiomers of these derivatives are efficiently separated on an amide‐derived chiral stationary phase. The chromatographic separations enable accurate determination of optical purity of the chiral β‐ lactams, prepared from homochiral ester enolate‐imine condensation. The absolute configuration of the major enantiomer of the β‐amino acid derivatives was determined from elution order on a chiral column.

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Key Word Index -Citr us t ank an ; (lavonoids ; hesperidin; li monin ; [er ul ic acid, Seven kinds of flavones , fl-sitostcroJ, fi-sitosterol-D -g luco side , hesperidin, limonin, ferulic acid and succinic acid were isolated from the fruit peel of Citrus tankan Hay ata .