Macrolidic antibiotics

In an attempt to synthesize the macrolide antibiotic chlorothricolide, an unhindered —COOH group was selectively protected, in the presence of a hindered —COOH group, as a MEM ester that was then reduced to an alcohol group. ... 

Many natural products are lactones, and it is not unusual to find examples in which the ring size is rather large. A few naturally occuning lactones are shown in Figure 19.8. The macrolide antibiotics, of which erythromycin is one example, are macrocyclic (large-ring) lactones. The lactone ring of erythromycin is 14-membered. 

Total syntheses of pyrrole alkaloids, furanoterpenes, macrolide antibiotics, and carbohydrates based on transformations catalyzed by transition metals 99SL1523. 

Configurational assignment of polyene macrolide antibiotics using the [ C]ace-tonide analysis 98ACR9. 

Discovery and development of a novel immunosuppressant. Tacrolimus hydrate (FK-506), macrolide antibiotic with piperidine and tetrahydrofuran fragments 97YZ542. 

Progress in the synthesis of chiral natural macrolide antibiotics epothione B and tartrolonB 99JHC1421. 

Therapeutic Function Topical antifungal Chemical Name Heptaene macrolide antibiotic Common Name —... 

The fungus Streptomyces erythreus is the source of a number of structurally related macrolide antibiotics that are collectively known as the erythromycins. The erythromycins occupy a prominent position in medicine by virtue of their useful antibacterial properties. Their use in therapy over the course of the last three decades has been widespread, and has resulted in the saving of many human lives. In this chapter, we address the landmark total synthesis of erythronolide B (1), the biosynthetic precursor of all the erythromycins, by E.J. Corey and his coworkers which was carried out at Harvard in the 1970s.1... 

The body of chemistry described above for amphotericin B (1) allowed, for the first time, the preparation of a series of novel derivatives of this polyene macrolide antibiotic and set the stage for a total synthesis of this target molecule. Below we unfold the adventure that led to the accomplishment of this goal.910... 

Dexamethasone, the macrolide antibiotic triacetylo-leandromycin, and phenobarbital are all well established inducers of the CYP3A subfamily, and can increase microsomal 4-hydroxylation of RA in rat liver. To what extent this is also the case for humans is not completely clear. 

The utility of RCM methodology for the synthesis of open-chain building blocks from a,fi-unsaturated d-lactones is exemplified by the partial syntheses of Cossy aimed for (+)-methynolide (the aglycon of the methymicin family of macrolide antibiotics) [45], and the anticancer agent discodermolide [46], as well as during a recent total synthesis of the highly cytotoxic marine natural depsipeptide apratoxin A by Forsyth and Chen [47]. 

Scheme 78 Novel ring-contraction metathesis of macrolide antibiotics with a 1,3-diene moiety [164]...

For a high-yielding ring contraction in the series of macrolide antibiotics containing a 1,3-diene unit, see Scheme 78... 

Figure 10.9 NeuA catalyzed preparation of a synthetic precursor to the macrolide antibiotic amphotericin B.

Using FmA catalysis and protected 4-hydroxybutanal, compound (97) has been stereoselectively prepared as a synthetic equivalent to the C-3-C-9 fragment of (-F)-aspicillin, a lichen macrolactone (Figure 10.35) [160]. Similarly, FruA mediated stereoselective addition of (25) to a suitably crafted aldehyde precursor (98) served as the key step in the synthesis of the noncarbohydrate , skipped polyol C-9-C-16 chain fragment (99) of the macrolide antibiotic pentamycin [161,162]. 

Figure 10.35 Stereoselective generation of chiral precursors for the synthesis of the lichen macrolactone (+)-aspicillin and the macrolide antibiotic pentamycin using FruA catalysis.

Macrolide antibiotic from cultures of Streptomyces mycawfaciens. Midecamycin Aj, Aj and A4 exist also in small amounts in the complex beside main component Midecamycin. 

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