摘要:
This invention relates to a cyclization process useful in the preparation of a key intermediate in the preparation of an endothelin antagonist of the general formula shown below: ##STR1##
摘要:
The present invention relates to an oxidation which converts a primary or secondary alcohol of Formula II: ##STR1## to an acid or ketone of Formula I: ##STR2## with periodic acid and a catalytic amount of a chromium reagent.
摘要:
The present invention relates to a periodic acid oxidation which converts the penultimate intermediate bearing a primary alcohol to the target endothelin antagonist compound of Formula I having a carboxylic acid.
摘要:
The present invention relates to an oxidation using sodium chlorite in the presence of a catalytic amount of TEMPO and sodium hypochlorite which converts the penultimate intermediate bearing a primary alcohol to the target endothelin antagonist compound of Formula I having a carboxylic acid ##STR1##
摘要:
The present invention relates to a TEMPO-catalyzed oxidation of primary alcohols, RCH.sub.2 OH to corresponding carboxylic acids, RCOOH in the presence of catalytic in the presence of catalytic amount of NaClO and stoichiometric amount of NaClO.sub.2 as an oxidant. ##STR1##
摘要:
This invention relates to an asymmetric synthesis of sulfides via a chiral sulfoxide directed stereospecific reduction of α,β-unsaturated sulfoxide to the saturated sulfide. These sulfides can be useful as selective estrogen receptor modulators or anti-neoplastic agents.
摘要:
An improved process is described which utilizes tetrachloro-1,4(or 1,2)-quinone as an oxidant in the Doebner-Miller synthesis of 7-chloroquinaldine, a starting material in the preparation of leukotriene antagonists. The process improves yield and eliminates the need of forming a ZnCl.sub.2 complex to isolate the end product.
摘要:
Imidazolmethyloxy-substituted tricyclo-macrolide immunosuppressants are prepared by reacting a tricyclo-macrolide with an imidazolmethyl trichloroacetimidate in the presence of an acid. The invention further provides a crystalline salt of imidazolmethyloxy-substituted tricyclo-macrolide, as well as novel compounds useful in the process of the present invention.
摘要:
The present invention is drawn to a process for forming an amide bond linkage comprising reacting a carboxylic acid and an amine in a two-phase mixture of water and an organic solvent selected from an oxygenated organic solvent or an aromatic solvent in the presence of a coupling reagent and an additive. This process is useful for making ubiquitous amides and polypeptides having various biological activities.
摘要:
The present invention is drawn to a process for forming an amide bond linkage comprising reacting a carboxylic acid and an amine in a two-phase mixture of water and an organic solvent selected from an oxygenated organic solvent or an aromatic solvent in the presence of a coupling reagent and an additive. This process is useful for making ubiquitous amides and polypeptides having various biological activities.