A concise convergent synthesis of 6-epi-erythronolide B 3,5-acetonide and of (9R)-dihydro-6-epi-erythronolide B from (R)-2, 3-O-isopropylideneglyceraldehyde is described. The key step in the synthesis involves the coupling of two aldehydes, comprising the C1-C6 and the C9-C13 portions of the target molecule, across a formal acetylide dianion (C7-C8 (Scheme 1).