An elegant synthesis of Zetaclausenamide.
Zetaclausenamide, which was isolated as a hepatoprotective agent from the leaves of medicinal plant Clausena lansium, was synthesized for the first time in six steps including Darzen's condensation, photoisomerization, and the final cyclization reactions.
Palladium-catalyzed intramolecular C–H amidation: synthesis and biological activities of indolobenzazocin-8-ones
Abstract The synthesis of multi ring-fused indolobenzazocinone derivatives, an antimitotic agent, has been carried out using palladium-catalyzed C–H activation/intramolecular amidation of benzo[ d ]azocinones, which were synthesized by the ring annulations of dihydroisoquinolines and azlactone in refluxing acetonitrile. The target compounds, indolobenzazocin-8-one derivatives, were evaluated for their cytotoxicity against the cancer cell lines HUCCA-1, A549, HepG2, and MOLT-3. The results showed that an unsubstituted indolobenzazocin-8-one 1e exhibited very good activities in the nanomolar IC 50 value range (HepG2 and MOLT-3).
A peptide muscarinic toxin from the Green Mamba venom shows agonist-like action in an inhibitory avoidance learning task.
A peptide, muscarinic toxin 2 (MTX2), isolated from Dendroaspis angusticeps venom was previously shown to displace the specific binding of [3H]pirenzepine, a muscarinic M1 receptor ligand, from rat brain synaptosomal membranes. We have tested MTX2 for muscarinic agonist or antagonist actions in an inhibitory avoidance task in rats. Infusion of the muscarinic receptor antagonist scopolamine into the hippocampus of rats immediately after the training period produced amnesia, whereas the muscarinic agonist oxotremorine increased retention. When MTX2 was injected into the hippocampus of rats after the inhibitory avoidance task, it caused memory facilitation, which could be suppressed by the concomitant infusion of scopolamine. Hence, in this test, MTX2 showed muscarinic receptor agonist-like actions, which are probably mediated by the M1 subtype of muscarinic acetylcholine receptors.