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A series of tetracyclic imidazole derivatives 9a-9v and 10a-10h are prepared by multistep route starting from the known tricyclic diketones 2a-2d. Intermediary dibenzooxepin [4,5-d]imidazoles (3a, 3c) and dibenzothiepin [4,5-d]imidazoles (3b, 3d) are N-protected to 4e, 4f and to the isomeric compounds 5a, 5b and 6a, 6b. The isomeric compounds 5 and 6 are separated. Compounds 4, 5, and 6 are formylated at C(2) to afford 7a-7j. In the last steps, aldehyde group is reduced, then alkylated to the two sets of isomeric x-dimethylaminoalkyl derivatives 9a-9v. N-deprotection of 9i-9v led to the compounds 10a-10h. Assignment of the syn/anti structure to 5a and 6a was supported by 1D selective ROESY NMR spectra, whereas conformational mobility for the selected representatives 8a and 8b is studied by dynamic NMR. Activation energies (energy barriers for interconversion) are determined to be $11.5 and 16.2 kcal/mol, respectively. A series of derivatives 9 and 10 were tested in vitro for their antiinflammatory activity.

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Certain macrolide antibiotics, azithromycin included, possess anti-inflammatory properties that are considered fundamental for their efficacy in the treatment of chronic inflammatory diseases, such as diffuse pan-bronchiolitis and cystic fibrosis. In this study, we disclose a novel azithromycin analog obtained via Barton–McCombie oxidation during which an unprecedented epimerization on the cladinose sugar occurs. Its structure was thoroughly investigated using NMR spectroscopy and compared to the natural epimer, revealing how the change in configuration of one single stereocenter (out of 16) profoundly diminished the antimicrobial activity through spatial manipulation of ribosome binding epitopes. At the same time, the anti-inflammatory properties of parent macrolide were retained, as demonstrated by inhibition of LPS- and cigarette-smoke-induced pulmonary inflammation. Not surprisingly, the compound has promising developable properties including good oral bioavailability and a half-life that supports once-daily dosing. This novel anti-inflammatory candidate has significant potential to fill the gap in existing anti-inflammatory agents and broaden treatment possibilities.