Zhou Wei-Shan

Total Synthesis of Arteannuin and Deoxyarteannuin.

Abstract Arteannuin 1 is a new sesquiterpene lactone containing a peroxide linkage and is an antimalarial principle isolated from Artemisia annua L. . R(+)-Citronellal 5 as a starting material for the total synthesis was converted into 11R(-)-methyl dihydroarteannuinate 12 in 14 steps. The key intermediate 4 was obtained from compound 12 in 5 steps. The introduction of hydroperoxide in 4 by photooxidation followed by acid treatment gave 1 . Hydroxylation of 4 with osmium tetraoxide afforded deoxyarteannuin 2 .

Studies on the identification and syntheses of insect pheromones XXI stereoselective synthesis of all the possible optical isomers of the mosquito oviposition attractant pheromone

Abstract All the four optical isomers of the oviposition attractant pheromone of the mosquito Gulex pipiens fatigans were synthesized via Sharpless asymmetric epoxidation.

Stereoselective synthesis of (-)-(5R,6S)-6-acetoxy-5-hexadecanolide, the mosquito oviposition attractant pheromone

Abstract The natural mosquito oviposition attractant pheromone,(-)-(5R,6S)- 6-acetoxy-5-hexadecanolide ( 1 ) was synthesized from readily available 1,2-cyclohexanediol, using kinetic resolution of cyclic allylic alcohol by modified Sharpless asymmetric epoxidation reagent as the key step.

Studies on structure and synthesis of arteannuin and related compound xx. The structure of a new peroxidic arteannuin degradation product and the lactone configuration of related compound

Abstract Determination of structure of a new peroxidic product 3 obtained from the degradation of arteannuin 1 and lactone configuration of the related compound 4 by means of chemical transformation and X-ray analysis are described.

Study on the syntheses of brassinolide and related compounds. Part 14. Highly stereoselective construction of the side-chain of brassinosteroids utilizing the β-alkylative 1,3-carbonyl transposition of the steroidal 22-En-24-one

A stereoselective synthesis of the side-chain of brassinolide which involves β-alkylative 1,3-carbonyl transposition of the α,β-unsaturated ketone 3,6-diacetoxycholest-22-en-24-one is described. The overall yield of (22R,23R,24S)-22,23-isopropylidenedioxy-24-methyl-5β-cholestane-3α,6α-diol from 3α,6α-diacetoxy-5β-pregnane-20-carbaldehyde in six steps is 47%.