描述了一种新的多组分偶联反应,用于在手性二磺酰亚胺催化下对吡咯并[1,2- a ]吲哚的对映选择性合成。反应的高特异性是布朗斯台德酸催化剂具有多齿特性的结果。DFT计算的见解有助于解释最简单的3,3'-未取代的联萘催化剂所观察到的出乎意料的高对映选择性,这是通过合作性非共价相互作用网络实现过渡态稳定的结果。简单地在3和3'位置引入取代基引起了显着的对映反转,这是双萘衍生的布朗斯台德酸催化作用下这种现象的第一个报道实例,而是归因于不稳定的空间相互作用。
Indole-2-carbaldehyde compounds and blood sugar reducing compositions
申请人:Boehringer Mannheim GmbH
公开号:US04053624A1
公开(公告)日:1977-10-11
New indole-2-carbaldehyde compounds of the formula ##STR1## wherein R.sub.1 is lower alkyl R.sub.2 is hydrogen, halogen, or lower alkyl or alkoxy, With the proviso that when R.sub.2 is halogen or ethyl, R.sub.1 can also be hydrogen And the physiologically compatible derivatives thereof, are outstandingly effective in lowering excessive blood sugar in mammals.
Dyeing process using a specific compound containing active methylene and a compound chosen from a specific aldehyde, a specific ketone, a quinone and a diiminoisoindoline or 3-aminoisoindolone derivative
申请人:Andrean Herve
公开号:US20070130702A1
公开(公告)日:2007-06-14
The present invention relates to the use, for dyeing keratin fibres, of at least one specific compound containing active methylene and of at least one compound chosen from an aldehyde, a ketone, a quinone and a diiminoisoindoline or 3-aminoisoindolone derivative, which makes it possible to obtain, by reaction without an oxidizing agent, a coloration of the said keratin fibres.