total synthesis of (-)-cytoxazone 1 was achieved in six linear steps (34% overall yield) from p-anisaldehyde. The key steps in this route are the regioselective and stereoselective introduction of a N-protected amine group, using the CSI reaction of the anti-1,2-dimethyl ether 3, and the subsequent regioselective cyclization of the N-protected amino diol 13 to give the 2-oxazolidinone unit of (-)-cytoxazone
A concise synthesis of (−)-cytoxazone and its stereoisomer (−)-4-epi-cytoxazone, novel cytokine modulators, has been accomplished each in six steps from readily available p-anisaldehyde with good diastereoselectivity. Key steps in the synthesis include the regioselective and diastereoselectiveamination of anti- and syn-1,2-dimethyl ethers with chlorosulfonylisocyanate and the subsequent regioselective
(-)-cytoxazone及其立体异构体(-)-4- Epi- cytoxazone(新型细胞因子调节剂)的简明合成已由易于获得的对-茴香醛以良好的非对映选择性在六个步骤中完成。合成的关键步骤包括用异磺酰氯磺化抗-和顺-1,2-二甲基醚的区域选择性和非对映选择性胺化,以及随后二醇的区域选择性环化反应,以构建恶唑烷-2-酮核。Cieplak电子模型通过S N 1机理和邻近基团效应解释了使用CSI进行胺化反应的非对映选择性,从而保留了构型。
An efficient stereoselective synthesis of (+)-deoxoprosophylline
作者:In Su Kim、Chae Baek Ryu、Qing Ri Li、Ok Pyo Zee、Young Hoon Jung
DOI:10.1016/j.tetlet.2007.07.034
日期:2007.9
An efficientstereoselectivesynthesis of (+)-deoxoprosophylline from readily available p-anisaldehyde is described. Key steps in the synthesis include the stereoselective amination of anti-1,2-dibenzyl ether using chlorosulfonyl isocyanate, intermolecular olefination, and Pd-catalyzed intramolecular cyclization.
An efficient stereoselective synthesis of (2S,3S)-3-hydroxypipecolic acid using chlorosulfonyl isocyanate
作者:In Su Kim、Yun Jung Ji、Young Hoon Jung
DOI:10.1016/j.tetlet.2006.08.040
日期:2006.10
3S)-3-hydroxypipecolic acid and (2R,3S)-2-hydroxymethylpiperidin-3-ol were achieved from p-anisaldehyde via the regioselective and diastereoselective introduction of an N-protected amine group usingchlorosulfonylisocyanate, ring-closing methathesis, and oxidation of p-methoxyphenyl group as the key steps.