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Figure 18. Comparison of HIV-1 protease binding conformations for cyclic urea inhibitor 161 (PDB entry: 1dmp) (orange) and linear peptidic substrate (PDB entry: 1mt7) (green). Images were generated using Insight II.

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The alkoxytriphenylphosphonium ion intermediate of the Mitsunobu reaction can be generated using the Hendrickson reagent, triphenylphosphonium anhydride trifluoromethanesulfonate, 1. Strangely, while the reagent 1 can be used in place of the Mitsunobu reagents (triphenylphosphine and a dialkylazodicarboxylate) for the esterification of primary alcohols, secondary alcohols such as menthol undergo elimination. Evidence is presented to show that this unexpected result is due to the presence of trialkylammonium triflate salts. Such salts lead to a dramatic decrease in the rate of esterification relative to competing elimination. The Mitsunobu esterification of menthol with p-nitrobenzoic acid was re-examined and the occurrence of elimination reported for the first time. The presence of traces of tetrabutylammonium triflate led to a dramatic reduction in the yield of inverted ester and a corresponding increase in the yield of anti elimination product 2-menthene. The mechanism of the Mitsunobu reaction is discussed in the light of the dramatic salt effect on both the rate and outcome of the reaction and the possible involvement of ion pair clustering. In contrast, use of the reagent 1 resulted in syn elimination to give a 1:2 mixture of 2- and 3-menthenes. Finally, 1 and sodium azide can be used to convert a primary alcohol into an azide in high yield. There was no reaction under Mitsunobu conditions.

Success in undergraduate chemical experiments requires students to develop knowledge and skills of instrumentation, equipment and chemical techniques. In this technology report, we propose an adaptable and user focused strategy to improve students' foundational skill and proficiency with chemical laboratory techniques and instrumentation. The strategy is composed of multi-perspective filming of experimental activities using mobile phones or professional level filming to create videos that can be freely viewed by students in-situ during laboratory classes on a mobile device (iPad). Details of mixed digital approaches for a variety of chemical experimental techniques (10 examples) are compared for professional level filming and mobile phone filming. Results showed that both the accuracy and precision of the developed videos are highly suitable for teaching purposes. Use of mobile phone cameras permitted chemical techniques to be filmed from multiple angles in constrained spaces, such as fume hoods. A major benefit to students was the utility of the videos on portable devices, as students were informed by the video whilst setting up or performing the task in hand during laboratory sessions.

Beta-hydroxy amides 6 and 7 were treated with triphenylphosphonium anhydride trifluoromethane sulfonate (3), or the cyclic analogue 4, to generate 2-oxazolines 5 and 8 under mild conditions. The reaction was optimised by examining the number of equivalents of reagents 3 or 4, or diisopropylethyl amine required to best effect cyclisation. The effects of altering the reaction temperature, reaction time, concentration, solvent, and addition rate also were investigated. However, it was found that use of a trityl group to block reaction at the hydroxyl or thiol group of the starting amides, and subsequent in situ detritylation, in the absence of base, led to greatly improved yields. Reagent 4 offered significant advantages in the purification of products and was used to dehydrate a range of trityl derivatives to form simple oxazolines, thiazolines, and a dihydro-1,3-oxazine, in high yield (85-99%), as well as a tetrahydro-1,3-oxazepine (31%).

In this paper, insight into forensic science students' experiences of a case-based scenario with an interdisciplinary guided-inquiry experience in chemistry and biology is presented. Evaluation of student experiences and interest showed that the students were engaged with all aspects of the case-based scenario, including the curriculum theory components as well as the active learning within interdisciplinary laboratories. Working in groups of three during laboratories was favored by students, but mixed responses for group assessment were observed. Since the introduction of the case-based scenario, sustained improvements in student assessment outcomes were observed. Questionnaire respondents indicated a strong interest in case-based learning. We propose a methodology framework for the case-based scenario investigation in forensic science and discuss the student experiences and improved learning occurring with the scenario involving an interdisciplinary guided-inquiry experience in chemistry and biology. This work suggests that an interdisciplinary guided-inquiry learning approach, ideally contextualized within a case-based scenario, is adaptable to other science discipline combinations.

Glycogen phosphorylase (GP) is an important target for the development of anti-hyperglycaemic drugs. GP is an enzyme which is moderated allosterically with multiple ligand binding sites where inhibitors can potentially modulate enzyme activity. The search for potent and isoform selective inhibitors of GP is ongoing with an increasing focus on allosteric inhibition. In this review, the structural diversity, and enzyme interactions of the most recent inhibitors, and in particular allosteric inhibitors, of GP at the different key binding sites are explored. A range of inhibitors of GP, with known as well as unknown binding site or mechanism is presented.