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The first synthesis of (+)-botryolide-E and its C-7 epimer has been achieved in 8 steps from d -Glucono-δ-lactone, and their antibiotic activities were also investigated preliminarily.

An organocatalytic approach to the synthesis of (2R,3S)-hexane-1,2,3,5-tetraol (11) derivatives (in the forms of different stereoisomers and bearing different protecting groups) has been developed. The key chiral intermediates 11 were prepared with complete stereocontrol through the proline-catalyzed intermolecular aldol reaction between acetone and d-glyceraldehyde acetonide. The synthetic utility of the intermediates was demonstrated by their transformation into the title hydroxylated pyrans and a variety of unsaturated lactones through standard synthetic protocols.

A concise synthesis of a chiral hexane-tetraol intermediate is achieved from d -glucono-δ-lactone in 6 steps featuring the successively selective deoxygenation. The versatile intermediate can be easily converted into the γ-lactone compound botryolide E and tetrahydropyran derivative ophiocerins A-C respectively. In addition, the direct transformation of ophiocerin C to ophiocerins A and B by Mitsunobu reaction was studied for the first time.

The stereoselective total synthesis of the naturally occurring γ-lactone derivative botryolide E (1) was accomplished with acetaldehyde as the starting material (Scheme 2). The asymmetric allyl boration, asymmetric dihydroxylation, chelation-mediated diastereoselective vinylation, and ring-closing metathesis reaction are the key steps. The method can conveniently be utilized for the preparation of other related γ-lactone derivatives.

A simple highly concise protective group-free synthesis of botryolide-E from (R)-propylene oxide was developed using Hoveyda Grubbs cross metathesis, Still’s modified Horner–Wadsworth–Emmons reaction, and Sharpless asymmetric dihydroxylation, as key steps.

An efficient stereoselective total synthesis of botryolide-E by a chiral-pool approach is described.