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In this introductory organic chemistry experiment, the students get an opportunity to analyze and identify an unknown compound as it is done in a real-laboratory setting. First, students are instructed on the proper operation of three major instruments, NMR, IR, and GC–MS, and are given a sample of an unknown compound. The students are expected to operate these three instruments on their own so as to obtain 1H NMR, 13C NMR, IR, and MS spectra of their unknown sample. They must then interpret the data from each of the four spectroscopic methods simultaneously to elucidate the chemical structure of the unknown compound. In this exercise, the instructor does not provide a list of possible unknowns so as to narrow the search for the students. All the knowledge about the nature of the compound is obtained from the spectral data.

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Nitrogen-containing sugar analogues, known as azasugars or iminosugars, such as polyhydroxylated piperdines, pyrrolidines, pyrrolizidines, and indolizidines, have the potential to become important therapeutic agents due to their ability to inhibit glycosidases. Synthetic pathways that are able to systematically produce a variety of these azasugars are eagerly sought after, since even minute structural or stereochemical changes often significantly alter the degree of inhibition. The synthesis of tetrahydroxylated pyrrolizidines 40 and 41 starting from methyl alpha-d-glucopyranoside is described and will be used as a template to develop syntheses of all the stereoisomers of polyhydroxylated pyrrolizidine 9 as well as other analogous bicyclic polyhydroxylated iminosugars. The key steps in this synthesis involve a one-pot conversion of a halopyranoside to a divinylamine by employing a simultaneous Zn reduction and reductive amination of the resulting aldehyde. After protection of the amine, a ring-closing metathesis results in a multifunctional eight-membered ring that then undergoes an internal S(N)2 cyclization to form an alkene-containing pyrrolizidine 33. Dihydroxylation of the alkene followed by hydrogenolysis of the benzyl protecting groups results in tetrahydroxylated pyrrolizidines 40 and 41.