Erythromycin

Erythromycin is a wide-spectrum antibiotic that was first isolated by J. M. McGuire and co-workers from a strain of the bacterium Streptomyces erythreus(now called Saccharopolyspora erythraea) found in a soil sample from the Philippines. Its action is similar to that of penicillins. Erythromycin exists in three forms, the most common of which, erythromycin A, is shown here.

In 1981, R. Woodward’s research group reported the first stereocontrolled synthesis of erythromycin A. It required 55 reaction steps. Over the years, the number of steps has been gradually lowered. This year, M. J. Kirsche and co-workers at the University of Texas, Austin, used the recently developed crotylation reaction to make a key intermediate and reduced the overall synthesis to 14 steps.