The absoluteconfiguration of plakoside A (2S,3R,11R*,12S*)-2-[(2′′′R,5′′′Z,11′′′R*,12′′′S*)-2′′′-hydroxy-11′′′,12′′′-methylene-5′′′-docosenamido]-1-O-[2′-O-(3′′-methyl-2′′-butenyl)-β-d-galactopyranosyl]-11,12-methylene-1,3-docosanediol} was determined as 11S,12R,11′′′S,12′′′R by its degradation to two cyclopropane-containing fatty acids followed by their derivatization with a chiral reagent and subsequent
白果糖苷A (2 S,3 R,11 R *,12 S *)-2-[(2''' R,5''' Z,11''' R *,12''' S *)-2'''-羟基-11'',, 12'''-亚甲基-5''-二十二碳三烯基] -1- O- [2'- O-(3''-甲基-2' ′-丁烯基)-β-d-吡喃半乳糖基] -11,12-亚甲基-1,3-二十二烷二醇}通过降解为两个环丙烷而确定为11 S,12 R,11''' S,12''' R含脂肪酸,然后用手性试剂将其衍生化,然后对所得衍生物进行HPLC分析。
Enantioselective synthesis of phomallenic acid C by In- and Pd-mediated anti-SN2′ coupling
Enantioselective synthesis of phomallenic acid C, an inhibitor of bacterial FAS II pathway, was succeeded. Allenyldiyne structure was constructed by a direct anti-SN2′ coupling of propargyl mesylate with diynylindium in the presence of palladium catalyst. Enantiomeric purity was determined by Ohrui–Akasaka method to be 96% ee.
细菌FAS II途径抑制剂磷丙二酸C的对映选择性合成成功。烯丙基二炔结构是通过在钯催化剂存在下,将炔丙基甲磺酸酯与二炔基吡啶直接抗-S N 2'偶联而构建的。通过Ohrui–Akasaka方法测定对映体纯度为96%ee。
Structure of an Unsaturated Fatty Acid with Unique Vicinal Dimethyl Branches Isolated from the Okinawan Soft Coral of the Genus Sinularia
A new unsaturated fatty acid with unique vicinal dimethyl branches was isolated from the Okinawan soft coral of the genus Sinularia. The structure of the compound was determined based on the results of spectroscopic analysis and chemical conversion. The absolute configuration was deduced by applying the Ohrui–Akasaka method.
Penasulfate A, a New α-Glucosidase Inhibitor from a Marine Sponge<i> Penares </i>sp.
作者:Yoichi Nakao、Takashi Maki、Shigeki Matsunaga、Rob W. M. van Soest、Nobuhiro Fusetani*
DOI:10.1021/np049939e
日期:2004.8.1
A new (alpha-glucosidase inhibitor, penasulfate A, has been isolated from a marine sponge Penares sp.(1) Its structure was elucidated by spectral and chemical methods to be a scalemic mixture of methyl pipecolates acylated with a novel sulfated fatty acid.