Total synthesis of auripyrone B using a non-aldol aldol-cuprate opening process.
نویسندگان
چکیده
A non-aldol aldol-cuprate opening generates the polypropionate 11 from the epoxy ether 14 in eight steps as a single diastereomer. A highly stereoselective aldol reaction of 8 with 9 gives the aldol product 7 in high yield and excellent diastereoselectivity, due to double stereodifferentiation. This compound was used for an efficient synthesis of the natural product auripyrone B 2 in only 20 steps and 8% overall yield from 14 using a late-stage spiroketalization onto a stable hemiketal as the final key step.
منابع مشابه
Total synthesis of auripyrones A and B and determination of the absolute configuration of auripyrone B.
Compounds containing the g-pyrone functional group have been isolated from marine animals (Figure 1). These compounds show valuable biological activities: for example, peroniatriols I (1) and II (2) exhibited significant cytotoxicity against L1210 cells. Also, vallartanone B (3) and onchidione (4) are chemical defense compounds of mollusks. Therefore, the development of a method to synthesize g...
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[formula: see text] The synthesis of all four diastereomers of bis(propionates), 3,5-dialkoxy-2,4-dimethylalkanals, by non-aldol aldol chemistry is described. The epoxy alcohols (3, 4) were converted into the mesylates (9, 11) which were cleanly rearranged to the desired 3,5-bis(oxygenated)-2,4-dimethylalkanals (10, 12) in high yield. The epoxy mesylates (13, 16) gave the desired products (14, ...
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عنوان ژورنال:
- Organic letters
دوره 12 12 شماره
صفحات -
تاریخ انتشار 2010