呋喃呋喃糖苷方法是最近开发的一种通过衍生化为β-d-和β-1-呋喃呋喃糖苷来确定仲醇的纯净构型的新方法,适用于六种被甲基和两个亚甲基取代的手性叔醇(1至6)组。的Δδ值(δ大号- δ d)质子和碳的从衍生1 H和13 C NMR谱在吡啶d 5。当观察到化合物时,呋喃糖基位于前面,甲基位于下面(图1B),则可以得出以下概括。(a)在1 H NMR中,ΔδH值在右段(R r)中的正质子为正,而在左段(R 1)中的质子为负(图2)。(b)在13 C NMR,在Δδ Ç值为正为正确的β碳原子和负的用于左β -碳,除了五元化合物5,这给了一个不明确的结果(图3)。
Alkyl-, Aryl-, Vinyl-, and Heterosubstituted Organozirconium Compounds. -Selective nucleophiles of low basicity. Preliminary communication
作者:Beat Weidmann、Christopher D. Maycock、Dieter Seebach
DOI:10.1002/hlca.19810640532
日期:1981.7.22
Solutions of the title compounds are accessible from organolithium reagents and trialkoxyzirconium chloride (equation 2). In contrast to their titanium analogues, vinylzirconium reagents are stable enough to be employed. Generally, organozirconium reagents are highly selective aldehyde and ketone carbonylophiles of exceedingly lowbasicity (Tables 1, 2, 3 and typical procedure).
Compounds are provided according to Formula (I): Formula (I) and pharmaceutically acceptable salts thereof, and pharmaceutical compositions thereof; wherein R
1
, R
2
, R
3
, R
6
, R
7
, R
8
, and n are as defined herein. Compounds of the present invention are contemplated useful for the prevention and treatment of a variety of conditions.