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The stereocontrolled total synthesis of the C31 apocarotenoid paracentrone was achieved by sequential cross-coupling reactions using C5 boronic acid ester and iodo-substituted dienes, which were newly developed building blocks for elongation of the conjugated polyene systems at both their terminals.

Highly functionalized α-2,3-methanoamino acid esters were prepared by the cyclopropanation of dehydroaspartic acid esters with 2-methoxyfuran or 2-siloxyfuran derivatives. These reactions proceed smoothly in the absence of any catalysts, bases, additives, or solvents.

The synthesis of anhydrorhodovibrin and two analogues has been achieved in a highly efficient manner using a new Horner–Wadsworth–Emmons reagent bearing the Weinreb amide.

Total syntheses of juvenile hormones JH 0 and JH I have been achieved by a new iterative enol tosylate homologation strategy.

K 2 HPO 4 is an efficient catalyst for thetransesterification reaction to produce methyl esters. Various functionalgroups are compatible under the mild reaction conditions.

Stereoselective construction of a tetraol system corresponding to C-5, 6, 7, and 11 in tetrodotoxin was achieved. Epoxidation of allyl sulfide 3 followed by base-induced ring-opening reaction gave hydroxyallyl sulfone 6. Repetition of the above reactions gave 1,3-dihydroxyvinyl sulfone 8, which was transformed to protected tetraols 18 and 20 by a series of sequential reactions: 1) reductive removal of the phenylsulfonyl group, 2) inversion of the α-axial TBSoxy group to an β-equatorial position, and 3) dihydroxylation with Oso 4 .

An efficient conversion of allyl sulfide 6 prepared from (-)-quinic acid (5) to gabosines was achieved by a series of sequential reactions: i) Mislow-Evans rearrangement, ii) SeO 2 oxidation, iii) conjugate addition of sodium hydroxide or sodium acetate, and iv) elimination of the methoxymethyloxy group.

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