β-Functionalization of Saturated Aza-Heterocycles Enabled by Organic Photoredox Catalysis
The direct β-functionalization of saturated aza-heterocycles has remained a synthetic challenge because of the remote and unactivated nature of β-C-H bonds in these motifs. Herein, we demonstrate the β-functionalization of saturated aza-heterocycles enabl
Holmberg-Douglas, Natalie,Choi, Younggi,Aquila, Brian,Huynh, Hoan,Nicewicz, David A.
p. 3153 - 3158
(2021/04/06)
Lipase-catalyzed practical synthesis of (R)-1-benzyl-3-hydroxy-2,5-pyrrolidinedione and its related compounds
A practical method for preparing (R)-1-benzyl-3-hydroxy-2,5-pyrrolidinedione (1) was investigated by the use of the enzymatic hydrolysis of its acetate (2a). Among several hydrolases examined here, lipase PS from Pseudomonas cepacia gave the best result: In a mixed solvent (1:1 v/v) of dioxane and a phosphate buffer (pH 7), the hydrolysis took place smoothly with a high enantioselectivity (E > 3000). Several 3-alkanoyl derivatives of 1 were subjected to the lipase PS-catalyzed hydrolysis. The chain length of the alkanoyl does not noticeably influence the reaction rate or the enantioselectivity. In contrast, the hydrolysis of the 1-benzoyl derivative proceeded slowly with a low enantioselectivity (E = 19). The syntheses of optically active 3-hydroxypyrrolidines and 3-hydroxypiperidines were also achieved under the reaction conditions similar to the lipase PS-catalyzed hydrolysis of 2a.
This disclosure describes novel 3 or 4 substituted oxotremorine derivatives having polar substituted oxygen or sulfur groups. The compounds have cholinergic activity. Also disclosed are methods for treating diseases of the central nervous system in mammals employing the compounds, pharmaceutical preparations containing the compounds and processes for the production of the compounds.
-
(2008/06/13)
More Articles about upstream products of 174621-88-6