Состав и содержание экдистероидов в растениях Silene fruticulosa (Pall.) Schischk

The ecdysteroid profile of Silene fruticulosa (Pall.) Schischk growing in Kazakhstan has been investigated. It has been shown that the plant contained ecdysterone (2.4 g/kg of dry weight), 2-deoxyecdysone (0.45 g/kg) and 2-deoxyecdysterone (0.11 g/kg).Предпринято изучение экдистероидного профиля смолевки кустарничковой Silene fruticulosa (Pall.) Schischk, которая встречается на всей территории Казахстана в природных местообитаниях. Показано, что надземные части данного растения содержат экдистерон (содержание 2.4 г/кг сухой массы), 2-дезоксиэкдизон (0.45 г/кг) и 2-дезоксиэкдистерон (0.11 г/кг)

New synthesis of castasterone

An improved synthesis that could produce gram quantities of castasterone was proposed. The starting material was stigmasterol, the cyclic part of which was transformed in the first synthetic step into the 3α,5-cyclo-6-ketone. The side-chain carbon skeleton in the target compound was constructed with the required stereochemistry of the C-24 methyl via addition of methylacetylene, hydrogenation of the propargyl alcohol over Lindlar catalyst, and Claisen rearrangement. Diols were introduced using Sharpless asymmetric dihydroxylation of the intermediate ∆2,22-dienone in the presence of (DHQD)2AQN. A unique feature of the synthesis was the avoidance of chromatographic separations of propargyl alcohols with similar chromatographic mobilities because the C-22 diastereomers were enriched in subsequent redox reactions

New synthesis of castasterone

An improved synthesis that could produce gram quantities of castasterone was proposed. The starting material was stigmasterol, the cyclic part of which was transformed in the first synthetic step into the 3α,5-cyclo-6-ketone. The side-chain carbon skeleton in the target compound was constructed with the required stereochemistry of the C-24 methyl via addition of methylacetylene, hydrogenation of the propargyl alcohol over Lindlar catalyst, and Claisen rearrangement. Diols were introduced using Sharpless asymmetric dihydroxylation of the intermediate ∆2,22-dienone in the presence of (DHQD)2AQN. A unique feature of the synthesis was the avoidance of chromatographic separations of propargyl alcohols with similar chromatographic mobilities because the C-22 diastereomers were enriched in subsequent redox reactions