This review deals with novel methods for a homologation of carbonyl compounds by using 1-chloroalkyl aryl sulfoxides as acyl anion equivalents. The products obtained from these methods are those of dialkyl ketones, aldehydes, α-substituted carbonyl compounds, vinyl-and divinyl ketones, 1-acylbutadienes, α, β-unsaturated carbonyl compounds, aldols, epoxides, allylic alcohols, (Z)-N-arylaziridines, and α-hydroxycarboxylic acids and their derivatives. Novel synthetic methods for cyclic ketones or new annulation procedures were achieved by using these new procedures. As the novel methods for asymmetric synthesis, a practical procedure for preparing optically pure 1-chloroalkyl p-tolyl sulfoxides was achieved. Optically active epoxides, (Z)-N-arylaziridines, α-amino aldehydes, and α-hydroxycarboxylic acids and their derivatives were synthesized from carbonyl compounds or imines and the optically active 1-chloroalkyl p-tolyl sulfoxides.
High-performance liquid chromatography (HPLC) with electrochemical detection has been developed for the trace analysis of electrochemically active substances in biological fluids such as catecholamines. The recent development of this system, both instruments and application, has been reviewed. The principle of instrument and newly developed electrode for electrochemical detector have been described at the first section. Series electrodes, especially with coulometric detection, gave much higher selectivity to the analysis of biological substances. The application of HPLC with electrochemical detection to the determination of estrogens in biological fluids clarified the metabolic pathway of catechol estrogens. The applicability to the determination of vitamin D3 and related compounds has been also suggested. For the purpose of extending the applicability of HPLC with electrochemical detection to electroinactive compounds, pre-and post-column labeling methods have been developed. Pre-column derivatization reagents possessing ferrocene as an electrophore provided a selective and sensitive response to the detector, because of their high-reversibility and low applied potential in the redox reaction. Post-column reaction by using immobilized enzyme reactor has been widely used for the determination of acetylcholine and choline in biological fluids.
Determinations of volatile components of essential oil contained in Asiasari Radix were studied by head space gas chromatography. The head space gas, which was generated by heating 0.2 g of crude drug with 1.0 ml of water at 90°C for 45 min, was analyzed directly by gas chromatography or gas chromatography-mass spectrometry. This method was rapid, and did not require tedious procedures and time consuming, and without contamination of the column.
Regional changes in concentrations of histamine (HA), serotonin (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in the rat brain were investigated after diarrhea induced by castor oil. Significant decreases in body weight were observed from the 3rd day after daily oral administration of castor oil (2.5 ml/kg). HA concentrations in most brain regions descreased in diarrhea induced by a single administration of castor oil. A significant decrease was recognized particularly in the case of the hippocampus. The influence has begun to appear in the thalamus and hypothalamus in consecutive (3 d) administration. HA concentration in the striatal and hypothalamic regions of the rat treated with castor oil for 9 d significantly decreased in comparsion with the control group. On the other hand, an inhibition of 5-HT turnover was observed in the thalamus at 3 h after a single administration of castor oil. However, this inhibition was not found in rats treated with castor oil for 3 d. Moreover, 5-HT concentration in the midbrain significantly decreased in rats that acquired the adaptability for the occurrence of diarrhea. These data present a new finding that the occurrence of diarrhea or acquisition of adaptability for diarrheal occurrence affects the central histerminergic or serotonergic neuron system.
To determine morphological changes in the very early stage of damage and recovery of myocardial fibers in relation to electrolytes and water content in the myocardium, experimental myocardial infarcts were produced after injection of 75 mg/kg isoproterenol (Isp) to rats weighing 270±10g. Electrolytes were exmined by an atomic absorption spectrophotometer, and histologic examination was performed by light and electron microscopy. At 30 min after Isp injection, Ca and water contents of myocardium increased, but Mg decreased. These myocardial damages showed a maximum level from 6 to 12 h after injection of Isp. It consisted of reversible injury of muscle fibers represented by eosinophilic and fatty degeneration, intermingled with coagulation necrosis of fibers which was irreversible. Most of these eosinophilic degeneration fibers recovered to normal fibers between 12 h and 3 d after the injection. The chronological changes of Ca, Mg, and water contents were well correlated to the morphological early changes of myocardial fibers, and this experimental model by using Isp may be useful for examining the recovery of damaged myocardial tissue and estimating the effects of therapeutics.
A study was carried out to examine the combined effect of arbutin isolated from the leaves of Arctostaphylos uva-ursi (L.) SPRENG. (Bearberry leaf) and indomethacin on Type IV allergic reaction-induced immuno-inflammation, carrageenin-induced edema and adjuvant-induced arthritis. Contact dermatitis caused by picryl chloride (PC-CD) and sheep red cell delayed type hypersensitivity (SRBC-DTH) was not inhibited by the oral application of arbutin at 2 divided doses immediately before and 16 h after the application, but arbutin at dose of 50 mg/kg 24 h after the application rapidly decreased the swelling of PC-CD. Arbutin (p. o.) plus indomethacin (s. c.) showed inhibitory effect on the swelling of PC-CD and SRBC-DTH stronger than that of indomethacin alone. When arbutin (p. o.) and indomethacin (s. c.) in a given portion were simultaneously administered, the inhibitory effect was more potent than that of indomethacin alone in both carrageenin-induced edema and adjuvant-induced arthritis. These results suggest that arbutin may increase the inhibitory action of indomethacin on PC-CD, SRBC-DTH, carrageenin-induced edema and adjuvant-induced arthritis, but further investigations are required to understand the mechanism involved.