反应详情

Compound 20 is treated with an organolithium base (e.g. LDA, t-BuLi or, preferably, n-BuLi) at low temperature (preferably −78° C.) in a solvent such as DME, Et2O or, preferably, THF, followed by treatment with an organo-disulfide, preferably diphenyldisulfide, to afford compound 28. Compound 29 is obtained by treating compound 28 with a base (e.g. LHMDS, LDA or, preferably, LTMP) at low temperature (preferably −78° C.) in a solvent such as THF, followed by aldehyde RMCHO. Compound 29 is treated with an oxidizing agent (e.g. KMnO4, PCC, PDC, “Swern” oxidation reagents such as (COCl)2/DMSO/Et3N or, preferably, MnO2 in CH2Cl2) to yield compound 30, which is treated with an oxidizing agent (e.g.hydrogen peroxide in acetic acid, 3-chloroperoxybenzoic acid in CH2Cl2, or, preferably, 3-chloroperoxybenzoic acid in Et2O) to provide compound 31. Desired compound 25 of the present invention is obtained upon treatment of compound 31 with H-A3-L3-Q3 in the presence of a base (e.g. KH or, preferably, NaH) in a solvent such as DMF, benzene, DME or, preferably, THF.

1. additionis treated with an oxidizing agent (e.g