Premium
Convergent Synthesis of Pancratistatin from Piperonal and Xylose
Author(s) -
Dam Johan Hygum,
Madsen Robert
Publication year - 2009
Publication title -
european journal of organic chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.825
H-Index - 155
eISSN - 1099-0690
pISSN - 1434-193X
DOI - 10.1002/ejoc.200900719
Subject(s) - chemistry , dihydroxylation , allylic rearrangement , xylose , yield (engineering) , bromide , diene , cyclohexene , organic chemistry , stereochemistry , combinatorial chemistry , enantioselective synthesis , catalysis , fermentation , materials science , natural rubber , metallurgy
A synthesis of the antitumour agent pancratistatin is described from piperonal and D ‐xylose. Piperonal is converted into cinnamyl bromide 11 while methyl 5‐iodoribofuranoside 12 is derived from xylose. The allylic bromide and the iodocarbohydrate are combined in a zinc‐mediated tandem reaction to afford a highly functionalised 1,7‐diene, which is then converted into the corresponding cyclohexene by ring‐closing olefin metathesis. Subsequent Overman rearrangement, dihydroxylation and deprotection afford the natural product in a total of 25 steps from the two starting materials. The longest linear sequence is from piperonal and gives rise to pancratistatin in 18 steps and 7.0 % overall yield. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)