Stereoselective Synthesis of Unnatural Analogs of (1)- Casuarine from Partially Protected DGDP
نویسندگان
چکیده
A new synthetic approach to analogs of (þ)-casuarine (2a and 2b), a natural pentahydroxylated pyrrolizidinic alkaloid in a highly stereocontrolled manner, is reported herein. An orthogonally protected polyhydroxylated pyrrolidine, such as (2S,3R,4R,5R)-3,4-dibenzyloxy-20-O-tert-butyldiphenylsilyl-2,5-bis(hydroxymethyl)pyrrolidine [3, protected DGDP (2,5-dideoxy-2,5-imino-D-glucitol)], easily available from D-fructose, was chosen as the source of chirality and functionalization.
منابع مشابه
Polyhydroxylated pyrrolizidines. Part 6: A new and concise stereoselective synthesis of (C)-casuarine and its 6,7-diepi isomer, from DMDP
A new synthesis for (C)-casuarine (1) and its 6,7-diepi isomer (15) in a stereocontrolled manner, is reported herein. An appropriately protected polyhydroxylated pyrrolidine, such as (2R,3R,4R,5R)-3,4-dibenzyloxy-2 0-O-tert-butyldiphenylsilyl-2,5bis(hydroxymethyl)pyrrolidine (3, protected DMDP), easily available from D-fructose, was chosen as the chiral starting material. Compounds 1 and 15 wer...
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تاریخ انتشار 2006