Kinetic resolution of vinyl carbonates through a lipase-mediated synthesis of their carbonate and carbamate derivatives.
摘要:
Lipase from Candida antarctica was used in the synthesis of different chiral carbonates and carbamates through the enzymic resolution of the starting racemic vinyl carbonates. A striking feature was the changeover of the enantioselectivity with regard to the one showed when vinyl carbonates were used in the resolution of alcohols and amines, thus the S enantiomer of the vinyl carbonate was resolved whereas the same enzyme was selective towards R ones when resolving alcohols and amines. In this way, compounds obtained beforehand as R carbonates were now achieved as S ones with better e.e.'s and shorter reaction times.
Kinetic resolution of vinyl carbonates through a lipase-mediated synthesis of their carbonate and carbamate derivatives.
摘要:
Lipase from Candida antarctica was used in the synthesis of different chiral carbonates and carbamates through the enzymic resolution of the starting racemic vinyl carbonates. A striking feature was the changeover of the enantioselectivity with regard to the one showed when vinyl carbonates were used in the resolution of alcohols and amines, thus the S enantiomer of the vinyl carbonate was resolved whereas the same enzyme was selective towards R ones when resolving alcohols and amines. In this way, compounds obtained beforehand as R carbonates were now achieved as S ones with better e.e.'s and shorter reaction times.
VARIABLE OPTIC OPHTHALMIC DEVICE INCLUDING LIQUID CRYSTAL ELEMENTS
申请人:Johnson & Johnson Vision Care, Inc.
公开号:US20160363784A1
公开(公告)日:2016-12-15
Methods and apparatuses for providing a variable optic insert into an ophthalmic lens as set forth. An energy source is capable of powering the variable optic insert included within the ophthalmic lens. In some embodiments, an ophthalmic lens is cast-molded from a silicone hydrogel. The various ophthalmic lens entities may include electroactive liquid crystal layers to electrically control refractive characteristics.
Kinetic resolution of vinyl carbonates through a lipase-mediated synthesis of their carbonate and carbamate derivatives.
作者:Marcos Pozo、Vicente Gotor
DOI:10.1016/s0040-4020(01)81561-1
日期:1993.1
Lipase from Candida antarctica was used in the synthesis of different chiral carbonates and carbamates through the enzymic resolution of the starting racemic vinyl carbonates. A striking feature was the changeover of the enantioselectivity with regard to the one showed when vinyl carbonates were used in the resolution of alcohols and amines, thus the S enantiomer of the vinyl carbonate was resolved whereas the same enzyme was selective towards R ones when resolving alcohols and amines. In this way, compounds obtained beforehand as R carbonates were now achieved as S ones with better e.e.'s and shorter reaction times.