Patients meeting current American-European Consensus Conference ARDS criteria may have highly variable levels of lung injury and outcomes. A systematic method of assessing severity of lung injury is required for enrollment of patients with ARDS into randomized controlled trials. Clinical trial registered with www.clinicaltrials.gov (NCT 00435110).

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Glycals (1,2‐unsaturated, cyclic carbohydrate derivatives) readily undergo (catalyzed) substitution reactions at C‐1 accompanied by allylic rearrangement. This reaction, currently named Ferrier rearrangement, or the Ferrier I reaction, has established itself as a useful synthetic tool for carbohydrate transformations. By means of this reaction, glycals can be converted into highly useful 2,3‐unsaturated glycosides. This review summarizes recent developments in the use of promoters for the Ferrier rearrangement of O‐, N‐, C‐ and S‐nucleophiles with glycals.

Three modes of selectivity — enantio, stereo, and regio — are critically important for efficient organic synthesis. In the sub‐domain of oligosaccharide synthesis, the first is (usually!) irrelevant in view of the chiralities of the reacting partners. The challenge posed by the other two is compounded by the reality that “protecting groups” are the major, if not only, instruments by which control can be exercised. The role that O2 protecting groups play in stereocontrol of coupling reactions was formulated 60 years ago. In this microreview, evidence is presented which shows that O2 protecting groups also exercise regiocontrol. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

This chapter begins with an account of the serendipitous events that led to the development of n-pentenyl glycosides (NPGs) as glycosyl donors, followed by the chance events that laid the foundation for the armed-disarmed strategy for oligosaccharide assembly. A key mechanistic issue for this strategy was that, although both armed and disarmed entities could function independently as glycosyl donors, when one was forced to compete with the other for one equivalent of a halonium ion, the disarmed partner was found to function as a glycosyl acceptor. The phenomenon was undoubtedly based on reactivity, but further insight came unexpectedly. Curiosity prompted an examination of how ω-alkenyl glycosides, other than n-pentenyl, would behave. Upon treatment with wet N-bromosuccinimide, allyl, butenyl, and hexenyl glucosides gave bromohydrins, whereas the pentenyl analog underwent oxidative hydrolysis to a hemiacetal. Although the answer was definitive, an in depth comparison of n-pentenyl and n-hexenyl glucosides was carried out which provided evidence in support of the transfer of cyclic bromonium ion between alkenes in a steady-state phenomenon. It was found that for two ω-alkenyl glycosides having a relative reactivity ratio of only 2.6:1, nondegenerate bromonium transfer enabled the faster reacting entity to be converted completely to product, while the slower reacting counterpart was recovered completely. This nuance suggests that in the armed/disarmed coupling, such a nondegenerate steady-state transfer is ultimately responsible for determining how the reactants are relegated to donor or acceptor roles.Development of chemoselective armed/disarmed coupling led to another phase in the sequence of serendipities. During experiments to glycosylate an acceptor diol, it was found that armed and disarmed donor's glycosylated different hydroxyl groups. This observation caused us to embark on studies of regioselective glycosylation. One of these studies showed that it is possible to activate selectively n-pentenyl orthoesters (NPOEs) over other n-pentenyl donors, and that this chemoselective process enables regioselective glycosylation. As a result, reaction partners can be so tuned that glycosylation of an acceptor with nine free hydroxyl groups by an n-pentenyl orthoester donor carrying two free hydroxyl groups is able to furnish a single product in 42% yield. Experiments such as the latter suggest that the donor favors a particular hydroxyl group, and/or that a particular hydroxyl favors the donor. Either option implies that the principle of reciprocal donor acceptor selectivity (RDAS) is in operation.Such examples of regioselective glycosylation provide an alternative to the traditional practice of multiple protection/deprotection events to ensure that the only free hydroxyl group among glycosyl partners is the one to be presented to the donor. By avoiding such protection/deprotections, there can be substantial savings of time and material - as well as nervous anxiety.

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O-Ethylation of phthalides with Meerwein's reagent followed by reaction of the ensuing salts with pyrrole, results in the formation of 5-alkoxy-5-phenyl dipyrromethane derivatives, which function as ready precursors of ortho-substituted 8-aryl BODIPY derivatives by reaction with borontrifluoride etherate, an overall process that can be carried out in a one-pot operation.