Erythromycin synthesis

Scheme 1.5 The D-proline-mediated intramolecular aldol reaction in Woodward s erythromycin synthesis.

In the Woodward erythromycin synthesis, the lithium enolate of t-butyl thiopropionate was added to aldehyde (151) aldol (152) was obtained in 85% yield (equation 99). The remarkable diastereofacial selectivity observed in this reaction may be a general property of thioester enolates. (v/de infra). 

Table 1. Macrolactonization to form the 14-mem-bered ring in the erythromycin synthesis.

In view of the high macrolactonization yields for 10/11 (Table 1) the ultimate problem of the erythromycin synthesis are the 3-1 and... 

When a stone is thrown into a pond, several waves are produced in succession, gradually spreading until they finally cover the whole pond. The stone in macrolide synthesis was the news that R.B. Woodward had started the total synthesis of erythromcyin A in 1973. Some waves are represented by Masamune s methymycin synthesis in 1975, Corey s erythronolide synthesis in 1978 and Tatsuta s carbomycin and tylosin syntheses in 1977 and 1981. One of the biggest waves is Woodward s erythromycin synthesis in 1981. 

The Woodward erythromycin synthesis is based on the aldol coupling of the Ca-Cg (38) and C9-C13 (39) segments, both of which are prepared from a... 

Figure 1 Seco acid, used in erythromycin synthesis...

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