Bioxalomycin α2

In this tutorial review, which should be of general interest to synthetic organic chemists at large, recent progress in the total synthesis of the tetrahydroisoquinoline antitumor antibiotics cyanocycline A, naphthyridinomycin, bioxalomycin alpha2, and lemonomycin is highlighted in detail and some biological background information is given as well. Preparations of truncated derivatives and uncompleted synthetic approaches are also described. The literature coverage includes the newest research results through the year 2008.

The bioxalomycins, a novel complex of broad-spectrum antibiotics, were isolated from fermentations of Streptomyces viridodiastaticus subsp. "litoralis" LL-31F508. Bioxalomycin alpha 2, the major component of this complex, exhibited antibacterial activity. The MICs ranged from < or = 0.002 to 0.008 micrograms/ml for gram-positive organisms and from 0.50 to 4 micrograms/ml for gram-negative organisms. Bioxalomycin alpha 2 was found to be bactericidal and to inhibit bacterial DNA synthesis preferentially. Bioxalomycin alpha 2 protected mice from a lethal challenge with Staphylococcus aureus Smith. The 50% effective dose of bioxalomycin alpha 2 administered orally was 10 times greater than that when the drug was given subcutaneously or intravenously. These data suggest a stability or bioavailability problem when the compound is administered orally.