A stereoselective route to the spirobicyclic ring system of oscillatoxin D
摘要:
Using a model system, a stereoselective assembly of the 1-oxaspiro[5.5]undec-4-ene-8-one ring system of the antileukemic natural products oscillatoxin D and 30-methyloscillatoxin D was demonstrated. A key step was an intramolecular attack of the C1-C3 beta-ketoester enol on a silyl-activated 2,3-dihydro-4-pyranone to create a silyloxy analogue of the natural product's spirobicyclic ring system.
ACID ADDITION SALT OF UDENAFIL, PREPARATION METHOD THEREOF AND PHARMACEUTICAL COMPOSITION COMPRISING THE SAME
申请人:Lee Chan-Ho
公开号:US20110306762A1
公开(公告)日:2011-12-15
The present invention provides an acid addition salt of Udenafil, a preparation method thereof and a pharmaceutical composition comprising the same. The acid addition salt of Udenafil in which Udenafil is bonded to an organic acid selected from the group consisting of oxalic acid, benzenesulfonic acid, camphorsulfonic acid, cinnamic acid, adipic acid and cyclamic acid, has excellent solubility in an aqueous medium, water stability and crystallinity, thereby being suitably applied for a pharmaceutical composition.