Toyokichi Yoshizawa

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Incarvillateine (1), a new monoterpene alkaloid carrying a characteristic cyclobutane ring, has been found to show significant antinociceptive activity in a formalin-induced pain model in mice. To investigate the correlation between its structure and antinociceptive activity, and especially to study whether a cyclobutane ring is necessary or not for(More)
A higher concentration of kinsenoside, 3-(R)-3-beta-D-glucopyranosyloxybutanolide (1), was detected in the crude drug Anoectochilusformosanus, and A. koshunensis by HPLC analysis. A methylation reaction occurred to give methyl ester (4) when the lactone ring of 1 was cleaved by silica gel catalysis using methanol containing solvent used in the purification(More)
Incarvillea sinensis is a wild plant distributed in northern China. The dried whole plant has been traditionally used to treat rheumatism and relieve pain as an ancient Chinese crude drug. To investigate its antinociceptive activity, we evaluated several fractions derived from the methanolic extract of Incarvillea sinensis in the formalin-induced pain model(More)
The anti-inflammatory activities of alpha-truxillic acid (1) and 4,4'-dihydroxy-alpha-truxillic acid (2) as well as their monomer components (E)-cinnamic acid (3) and (E)-p-coumaric acid (4) were evaluated in the formalin test. alpha-Truxillic acid (1) and its derivative 4,4'-dihydroxy-alpha-truxillic acid (2) exhibited significant activity against(More)
To determine the antinociceptive mechanism of incarvillateine (INCA), the opiate antagonists nor-binaltorphimine (nor-BNI), beta-funaltrexamine (beta-FNA) and naltrindole (NTI) were pretreated prior to its injection in a formalin test. The antinociceptive effect of INCA was antagonized by nor-BNI (kappa-receptor antagonist) and beta-FNA (mu-receptor(More)
Our recent study demonstrated that the dimeric structure of alpha-truxillic acid derivatives played an important role in the expression of their anti-inflammatory activities. In the present report, to investigate the correlation between the structure and anti-inflammatory activity, alpha-truxillic acid (1) and its derivatives (2-6), beta-truxinic acid (7)(More)
Method for rapid quantitative analysis of incarvillateine in Incarvillea sinensis by high-performance liquid chromatography (HPLC) has been developed. The sample preparation involves solid phase extraction (SPE) with a mixed-mode reversed-phase and cation-exchange cartridge. The linear calibration range for incarvillateine was 0.002-0.5 mg/ml. The limit of(More)
The oral anti-inflammatory activity of 4,4'-dihydroxy-alpha-truxillic acid (1) was compared with that of two other nonsteroidal anti-inflammatory drugs, loxoprofen sodium (LOX) and diclofenac sodium (DIC). The activity of 1 against the inflammatory pain response induced by formalin was comparable to that of LOX, but weaker than that of DIC. In the(More)
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