Lividomycin structure

Figure 7.13. Chemical structure of lividomycin A. The arrow indicates the site of action of the phosphorylating enzyme, lividomycin phosphotransferase...

The structure of lividomycin B was established by conversion of lividomydn A into lividomycin B by means of the Barry degradation. 

Lividomycin A is pentacyclic and is structurally more complex than lividomycin B however, die former was suitable for 1-N-acylation. Reaction of penta-ZV-(benzyloxycarbonyl) lividomycin A with benzaldehyde dimethyl acetal gave a tribenzylidene derivative which, on treatment with sodium hydride in N,W-dimethylformamide, gave the cyclic carbamate 214. Of importance was the fact that, although there are two pairs... 

The structure, lividomycin 5"-phosphate, was furthermore proved by chemical synthesis. Penta-N-(benzyloxycarbonyl) lividomycin A was prepared from lividomycin A by the usual Schotten-Baumann procedure in a yield of 95% it had m.p. 135-150° (dec.). Acetonation with 2,2-dimethoxypropane in N,N-dimethylformamide in the presence of p-toluenesulfonic acid at 110° for 4 hours afforded the tri-O-isopropylidene derivative of N-(benzyloxycarbonyl)lividomycin A in 49% yield m.p. 129-133° (dec.). Phosphorylation of the sole primary hydroxyl group in the D-ribose moiety of -(benzyloxycarbonyl) lividomycin A with diphenyl phosphorochloridate in dry pyridine gave penta-N-(benzyloxy-... 

---