Three benzenetellurinic mixed anhydrides, i.e., benzenetellurinyl acetate, trifluoroacetate, and trifluoromethanesulfonate, have been found to be mild oxidizing agents for various substrates such as thiol, phosphine, acyloin, α-hydroxy ester, catechol, hydroquinone, thiourea, and thioamide. The reactions towards the last two substrates are highly chemoselective, depending on both the reagent and substrate.

Ring strips of monkey pulmonary veins precontracted with a high concentration of prostaglandin F2 alpha (PGF2 alpha) relaxed in a concentration-dependent manner in response to histamine. Treatment with mepyramine and/or famotidine attenuated the relaxation. 2-Pyridylethylamine (2PEA) and dimaprit caused relaxations in the precontracted preparations, which were inhibited by pretreatment with mepyramine and famotidine, respectively. Removal of endothelium reversed the histamine- and 2PEA-induced relaxations to dose-related contractions. On the other hand, the removal had no effect on the dimaprit-induced relaxations, which were significantly reduced by pretreatment with famotidine. Histamine-induced relaxations in the precontracted strips with endothelium in the presence and absence of famotidine were suppressed or abolished by treatment with methylene blue or hemoglobin but were unaffected by aspirin. It may be concluded that histamine-induced relaxation in monkey pulmonary veins precontracted with PGF2 alpha is mediated by H2-receptors in smooth muscle and H1-receptors in endothelium. Also, stimulation of the endothelial H1-receptors liberates an endothelium-derived relaxing factor.

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BackgroundMicafungin and caspofungin, which are both echinocandins, elicit their antifungal effects by suppressing the synthesis of β-D-glucan, an essential component of fungal cell walls. If micafungin is not effective against a fungal infection, is it unreasonable to switch to caspofungin?Case presentationAn 80-year-old Asian man presented to our hospital with brain and lung abscesses. Klebsiella pneumonia and Escherichia coli were identified by sputa culture and Streptococcus mitis was identified in the brain abscess culture obtained by drainage surgery. He was treated with antibiotics and both abscesses shrank after the treatment. But he continued to have a high fever and Candida glabrata was identified by blood culture. The origin of the infection was not clarified and micafungin was administered intravenously. The fungus showed poor susceptibility to micafungin; we then switched the antifungal from micafungin to caspofungin. After caspofungin treatment, his body temperature remained below 37 °C and his β-D-glucan levels decreased remarkably.Conclusions In vitro, micafungin is considered more effective against C. glabrata because its minimum inhibitory concentration against C. glabrata is lower than that of caspofungin. However, in vivo, there is no significantly different effect between the two drugs. When micafungin is not effective against candidiasis, a switch to caspofungin might be applicable because the pharmacokinetics in each echinocandin is slightly different.

Bis(p-methoxyphenyl) telluride (1) electrochemically reacted with supporting electrolytes such as tetrabutylammonium acetate and tetraethylammonium tosylate under anhydrous conditions to give tellurium(IV) diacetate 2a and ditosylate 2b, respectively. On the other hand, 1 was electrolyzed in the presence of water to give telluroxide 3. It has turned out that the tellurium compounds 2a and 2b like telluroxide 3 are mild oxidizing agents, but 2b behaves differently in a reaction towards thioamide. Thus 2a and 3 converted it into nitrile, while 2b did it into 1,2,4-thiadiazole. An indirect electrolytic oxidation of thioamides with 1 as a mediator was examined under various conditions. As a result, nitriles or 1,2,4-thiadiazoles could be chemoselectively formed, depending on the intermediacy of 2a or 3 as an active species for the former and 2b for the latter.