Cyclopropanation of Terminal Alkenes through Sequential Atom‐Transfer Radical Addition/1,3‐Elimination
作者:Nicholas D. C. Tappin、Weronika Michalska、Simon Rohrbach、Philippe Renaud
DOI:10.1002/anie.201907962
日期:2019.10
An operationally simple method to affect an atom-transfer radical addition of commercially available ICH2 Bpin to terminal alkenes has been developed. The intermediate iodide can be transformed in a one-pot process into the corresponding cyclopropane upon treatment with a fluoride source. This method is highly selective for the cyclopropanation of unactivated terminal alkenes over non-terminal alkenes
O,ω‐Unsaturated N‐tosyl alkoxyamines undergo unexpected RhIII‐catalyzed intramolecular cyclization by oxyamination to produce oxygen‐containing heterocycles. Mechanistic studies show that an aziridine intermediate seems to be responsible for the formation of the heterocycles, possibly via a RhV species.
The iodine/DMAP-mediated intramoleculartandem C–C/C–O bond forming reaction of malonate bearing alkene moiety proceeded to give bicyclic lactones with good diastereoselectivity in good yield. The mechanistic investigation was also discussed on the basis of various control experimental results.
There are provided compounds of the formula
wherein X, Y, R
1
, R
2
, R
3
, R
3
, R
4
, R
5
, R
6
and R
7
are as described herein and enantiomers and pharmaceutically acceptable salts and esters thereof. The compounds are useful as anticancer agents.
Substituted inmidazoles as bombesin receptor subtype-3 modulators
申请人:Chen David
公开号:US20100022598A1
公开(公告)日:2010-01-28
Certain novel substituted imidazoles are ligands of the human bombesin receptor and, in particular, are selective ligands of the human bombesin receptor subtype-3 (BRS-3). They are therefore useful for the treatment, control, or prevention of diseases and disorders responsive to the modulation of BRS-3, such as obesity, and diabetes.