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A four week laboratory experiment was designed on the basis of a modification of the Weiss–Cook reaction for the preparation of cis-1,5-dimethylbicyclo­[3.3.0]­octane-3,7-dione. In general, this very versatile organic reaction involves a two-step process reacting biacetyl with 2 mol of dimethyl-1,3-acetonedicarboxylate to form cis-bicycle­([3.3.0]­octane-3,7-dione). The reaction employs an aldol reaction followed by successive Michael reactions that are typically encountered near the end of a second-year undergraduate organic chemistry course. The students gained hands-on experience with 1H NMR and IR spectroscopy to analyze the intermediate and final product. Students wrote a formal laboratory report and discussed their results, including a proposal of the reaction mechanism and calculation of the overall yield. The experiment may be used in a traditional second semester organic chemistry laboratory or an advanced organic chemistry synthesis course on multigram or microscale levels.

performed a series of long molecular dynamics simulations for the SA or its mutants with/without biotin analog systems developed by kawato et al. to investigate the effect of mutations on the structural change, dynamics and the thermodynamic properties of the system. We also have calculated free energy of the systems using MPCAFEE method to evaluate binding affinity of artificial biotin analogs with SA mutants. We found that the mutations in the biotin-binding pocket affect not only the interaction with surrounding residues and with biotin analog, but also the tetramerization of the SA mutants.