Synthesis of 9-bromocotarnine and its recyclization into 4-acyl-9-bromo-7,8-methylenedioxy-1,2-dihydro-3-benzazepines with anti-infective activity

9-Bromocotarnine in the stable perchlorate form has been obtained by the interaction of cotarnine with bromine. The reaction of 9-bromocotarnine with α-haloketones is accompanied by the extension of the six-membered hetero-ring to seven-membered ring and led to previously unknown 4-acyl-9-bromo-3-methyl-6-methoxy-7,8-methylendioxy-1,2-dihydro-3-benzazepines. Some of these compounds have been shown to have only moderate antibacterial (against Staphylococcus aureus , Escherichia coli ) and fungistatic ( Penicillium italicum ) activities, but none of them has been shown to have a pronounced protistocidal activity against Colpoda steinii .