A synthesis of (R)-muscone (1), a valuable musk odorant, is presented. The stereogenic center of muscone was introduced from methyl (R)-5-bromo-4-methylpentanoate (5), a chiral pool molecule developed in our group, and the macrocyclic ring was prepared by ring-closing metathesis (RCM) reaction.

Starting from chiral methyl molecules 3 and 4, both derived from (R)-4-methyl-δ-valerolactone, we have accomplished the synthesis of (R) and (S)-3-methylheptanoic acids. Our methods are amendable to the syntheses of a wide variety of chiral 3-methyl alkanoic acids.

We report the first semisynthesis of the natural insect antifeedant azedarachol. The synthesis features the employment of pregnanetriol, a degradative product of the resource natural product tigogenin, as the starting material, the symbiotic reaction involving the mutually-promoting elimination of toluene-sulfonate and deprotection of acetonide, and the controllable reactions between the C16-OH and the C20-OH in pregnane-16,20-diols.

Based on chiral pool strategy, a synthesis of the C1–C9 domain of the proposed structure of didemnaketal A, a natural product with potent HIV-1 protease inhibitory activity, has been achieved. Key transformations are a Sharpless asymmetric dihydroxylation and a chelation-controlled allylation.

A formal synthesis of betamethasone from 5α-pregnane-3β,16β,20S-triol is described. Key transformations are a bromination-acetylation of triol, an S_N2 reaction of the resulting C16α-bromide with dimethylcopperlithium to get the required C16β-methyl group, and a double hydroxylation to prepare the dihydroxyacetone side chain.

Herein we report a synthesis of the natural tribolure, an aggregation pheromone which consists of (4R,8S)-, (4R,8R)-, (4S,8S)-, and (4S,8R)-4,8-dimethyldecanals in a ratio of 4/4/1/1, from (R)-4-methyl-δ-valerolactone, a byproduct of the degradation of steroidal sapogenins. Merging the stereoisomers of the same ratios into one synthetic target and using the same chiron for the construction of the C4 stereocenters are notable features of this synthesis.

Herein we describe a scalable four-step preparation of α-methylene-γ-lactone 3 from steroidal sapogenin. This method allowed a facile synthesis of clionamine D, a natural aminosteroid with potent autophagy bioactivity and unprecedented chemical structure.