Although the general outlines of erythromycin biosynthesis are by now well accepted, the details of the key chain-elongation process by which the macrolide carbon skeleton is assembled are still obscure.'Extensive investigations in our own2 and other laboratories' have demonstrated the role of propionate as the basic building block for the macrolide aglycone and established that the oxygen atoms at C-1, C-3,(2-5,(2-9, C-11, and C-13 are ...
