Arzneimittel Forsch
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The spinal nociceptive system is the target of various pain depressing agents. It is capable to function without control from the brain. It is activated by tissue damage which, by excitation of nociceptive afferents, evokes activity in axons ascending to the brain (sensory nociceptive response) and in spinal reflex pathways (motor and autonomic responses). ⋯ Ceruletide and cholecystokinin octapeptide depress nociceptive motor responses but do not affect the nociceptive sensory response. This indicates that motor and sensory responses of the spinal nociceptive system are not rigidly linked together. With the help of appropriate drugs, it is possible to manipulate them separately.
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Arzneimittel Forsch · Jan 1984
2-Acetylpyridine thiosemicarbazones. 10. 2-Propionyl-, 2-butyryl-, and 2-(2-methylpropionyl)pyridine thiosemicarbazones as potential antimalarial agents.
In view of the antimalarial properties observed for many 2-acetylpyridine thiosemicarbazones, a series of N4,N4-disubstituted thiosemicarbazones derived from 2-propionyl-, 2-butyryl-, and 2-(2-methylpropionyl)pyridine was prepared for evaluation against the malaria parasite, Plasmodium berghei, in the mouse. The thiosemicarbazones were made by the reaction of methyl hydrazinecarbodithioate with a 2-acylpyridine to give the intermediate methyl 3-[1-2-pyridinyl)alkylidene]hydrazinecarbodithioates. ⋯ The three thiosemicarbazones derived from 3-azabicyclo[3.2.2]nonane were most effective, the greatest potency being exhibited by 3-azabicyclo-[3.2.2]nonane-3-thiocarboxylic acid 2-[1-(2-pyridinyl)butylidene]hydrazide (4) which cured 4/5 mice at a dose of 160 mg/kg. In contrast to the related thiosemicarbazones derived from 2-acetylpyridine, virtually no toxic effects were observed in the series described here.