The synthesis of a series of alkylcarbamates of 1,5-methano-2,3,4,5-tetrahydro-1H-2-benzazepin-7-ol is reported. Many of these compounds are potent acetylcholinesterase (AChE) inhibitors. The in vitro AChE inhibition, cholinergic effects, acute toxicity, and elevation of brain acetylcholine levels in vivo of this series of compounds are described. A representative compound, 1d (5.6 mg/kg, po), was able to reverse hemicolinium-3-induced amnesia in the mouse passive avoidance assay.

The synthesis of a series of 1,2,3,3a,8,8a-hexahydroindeno[2,1-b]pyrrole 5-alkylcarbamates and their resolution are reported. These compounds are structurally related to physostigmine with substitution of a methylene group in place of the NMe group at position 8 of physostigmine. Many of these 8-carbaphysostigmine analogues are more potent acetylcholinesterase inhibitors in vitro and less toxic in vivo than physostigmine. The (-)-enantiomer (e.g., 1d and 1g) possessing the same absolute configuration at C3a and C8a as that of physostigmine, is about 6 to 12-fold more potent at inhibiting acetylcholinesterase than the corresponding (+)-enantiomer (e.g., 1e and 1h).

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A laboratory exercise was devised that allows students to rapidly and fairly accurately determine the iodine value of oleic acid. This method utilizes the addition of elemental bromine to the unsaturated bonds in oleic acid, due to bromine's relatively fast reaction rate compared to that of the traditional Wijs solution method. This method also uses pyridinium tribromide as a bromine source in an effort to eliminate many of the safety hazards of working with elemental bromine. After the addition of a known quantity of bromine to the reaction flask, excess bromine is reduced with potassium iodide forming elemental iodine. The elemental iodine is then titrated with sodium thiosulfate and a starch indicator in a back-titration to determine the amount of excess bromine added to the oleic acid. Students then determine the iodine value of oleic acid by using a 126 g iodine/80 g of bromine ratio. This exercise can yield results fairly close to the accepted iodine value of 90 for oleic acid, as several of the groups who tried out the experiment obtained iodine values close to 90. In addition, this exercise was also able to determine the iodine values of olive, coconut, and grapeseed oils. Finally, this experiment can be used to reinforce organic chemistry concepts as well as biochemistry concepts to IB Chemistry students.