Diastereoselectivity (Enantioselectivity) of Aldol Condensations Catalyzed by Rabbit Muscle Aldolase at C-2 of RCHOHCHO if R Has an Appropriately Placed Negatively charged Groupr
نویسندگان
چکیده
o-Fructose 1,6-bis(phosphate) aldolase from rabbit muscle (RAMA, 8.C.4.L.2.13) catalyzes the aldol condensation betwe.tr dihyd.oxyacetone phosphate (DHAP) and various aldehydes; the products are ketosugars with 3(S),4iR) stereochemistry. When racemic a-hydroxy aldehydes are condensed with DHAF, two diastereomeric products are formed. This paper demonstrates that RAMA can kinetically resolve a-hydroxy aldehydes with a negative charge removed four or five atoms from the atdehvdic center. Kinetic resolution of either uncharged a-hydroxy aldehydes, or of a-hydroxy aldehydes with a negative charge removed three or seven atoms from the aldehydic carbon, is generally
منابع مشابه
Gram scale synthesis of 3-fluoro-1-hydroxyacetone phosphate: a novel donor substrate in rabbit muscle aldolase-catalyzed aldol reactions.
An efficient gram scale synthesis of 3-fluoro-1-hydroxyacetone phosphate (FHAP) has been developed. As a close analog to dihydroxyacetone phosphate, FHAP was used as a novel donor substrate for rabbit muscle aldolase catalyzed reactions. The different binding affinities of the gem-diol and keto form of FHAP were studied by (19)F-NMR.
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