The first synthesis of dolabelide C (1), a cytotoxic marine macrolide, is reported utilizing a phosphate tether-mediated approach. Bicyclic phosphates (S,S,SP)-5 and (R,R,RP)-5 serve as the central building blocks for the construction of two major 1,3-anti-diol subunits in 1 through selective cleavage pathways, regioselective olefin reduction and cross-metathesis. Overall, phosphate-mediated processes provided copious amounts of both major subunits allowing for a detailed RCM macrocyclization study to the 24-membered macrolactone 1.

Iron contributes significantly to the formation of reactive oxygen species via the Fenton reaction. Therefore, we assessed whether a series of desferrithiocin analogs, both carboxylic acids and hydroxamates, could (1) either promote or diminish the iron-mediated oxidation of ascorbate, (2) quench a model radical species, 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+), and (3) when applied topically, prevent acetic acid-induced colitis in rats. Surprisingly, most of the desferrithiocin analogs inhibited the Fenton reaction to an approximately equivalent degree; however, substantial differences were observed in the capacity of the analogs to scavenge the model radical cation. Four carboxylic acid desferrithiocin analogs and their respective N-methylhydroxamates were tested along with desferrioxamine and Rowasa, a currently accepted topical therapeutic agent for inflammatory bowel disease (IBD), in a rodent model of acetic acid-induced colitis. The colonic damage was quantitated by two independent measurements. Although neither radical scavenging nor prevention of Fenton chemistry was a definitive predictor of in vivo efficacy, the overall trend is that desferrithiocin analogs substituted with an N-methylhydroxamate in the place of the carboxylic acid are both better free radical scavengers and more active against acetic acid-induced colitis. These results represent an intriguing alternative avenue to the development of improved IBD therapeutic agents.

Ophthalmic manifestations of inflammatory bowel disease are common, but orbital inflammatory disease is rare with most cases associated with Crohn disease. We describe the first case of bilateral, diffuse, orbital myositis associated with ulcerative colitis in a patient taking infliximab. Within 72 hours of intravenous methylprednisolone treatment, the orbital inflammation dramatically improved. After 8 weeks of prednisone, it completely resolved and has remained quiet for 13 months. This is only the third report of ulcerative colitis-associated orbital inflammatory disease.

Exploitation of the polyamine backbone as a vector for intracellular transport of various pharmacophores has focused largely on fixing the cargo molecule to one of the nitrogens in the linear chain. This communication describes the assembly of a model aminopolyamine analogue, 6-amino-N(1),N(12)-diethylspermine, and its biological properties. This amino polyamine presents an additional site of attachment for cargo molecules, reduces cell growth, and achieves cellular concentrations that are higher than those of N(1),N(12)-diethylspermine.

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