ISSN:
0170-2041
Keywords:
Naphthoquinone
;
Aldol addition
;
(R)-Shikonin
;
(S)-Alkannin
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The enantiomeric naturally occurring naphthoquinones shikonin [(R)-1] and alkannin [(S)-1] have been synthesized in a thirteen-step procedure in 44 to 65% e.e. The stereogenic centers of (R)-1 and (S) are created by the reaction of naphthaldehyde 3 with (R)- and (S)-2-hydroxy-1,2,2-triphenylethyl acetate (2), respectively. In order to find out a rationalization for the unexpectedly low diastereoselectivity in this aldol addition, a series of substituted aromatic aldehydes 12a-h has been treated with (R)-2.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jlac.1991199101199
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