Abstract
The synthesis of kynapcin-24, which can be isolated from the
Korean mushroom Polyozellus multiflex Murr,
is achieved in 12% overall yield from commercially available
3,4-dihydroxybenzaldehyde by a route in which the longest linear
sequence is only 14 steps. The key transformations in the synthesis
are copper-mediated and palladium-catalyzed coupling reactions of
the iodide 3-iodo-5,6-diisopropoxy-2-[(tetrahydropyran-2-yloxy)methyl]benzofuran
with the corresponding stannane 5,6-diisopropoxy-2-[(tetrahydropyran-2-yloxy)methyl]-3-(tributylstannyl)benzofuran,
and a 5-endo -dig iodocyclization
of a (hydroxyphenyl)propargyl ether.
Key words
kynapcin-24 - copper-mediated - palladium-catalyzed - coupling - cyclizations
References
<A NAME="RF22908SS-1">1 </A>
Yaron A.
Naider F.
Crit. Rev. Biochem. Mol. Biol.
1993,
28:
31
<A NAME="RF22908SS-2">2 </A>
Aoyagi T.
Wada T.
Nagai M.
Kojima F.
Harada S.
Takeuchi T.
Takahashi H.
Hirokawa K.
Tsumita T.
Experientia
1990,
46:
94
<A NAME="RF22908SS-3">3 </A>
Hwang JS.
Song KS.
Kim WG.
Lee TH.
Koshino H.
Yoo ID.
J. Antibiot.
1997,
50:
773 ; and references cited therein
<A NAME="RF22908SS-4A">4a </A>
Kim SI.
Park IH.
Song KS.
J. Antibiot.
2002,
55:
623
<A NAME="RF22908SS-4B">4b </A>
Song KS.
Raskin I.
J. Nat. Prod.
2002,
65:
76 ; and references cited therein
<A NAME="RF22908SS-5">5 </A>
Tseng TH.
Lee YJ.
Anticancer Agents Med.
Chem.
2006,
6:
347
<A NAME="RF22908SS-6">6 </A>
Chang CF.
Yang LY.
Chang SW.
Fang YT.
Lee YJ.
Tetrahedron
2008,
64:
3661
<A NAME="RF22908SS-7">7 </A>
Cheng CF.
Lai ZC.
Lee YJ.
Tetrahedron
2008,
64:
4347
<A NAME="RF22908SS-8">8 </A>
Lin SY.
Chen CL.
Lee YJ.
J.
Org. Chem.
2003,
68:
2968
<A NAME="RF22908SS-9">9 </A>
Benincori T.
Brenna E.
Sannicolò F.
Trimarco L.
Antognazza P.
Cesarotti E.
Demartin F.
Pilati T.
J. Org. Chem.
1996,
61:
6244
<A NAME="RF22908SS-10">10 </A>
Kelly TR.
Lee YJ.
Mears RJ.
J.
Org. Chem.
1997,
62:
2774
<A NAME="RF22908SS-11">11 </A>
Pla D.
Albericio F.
Álvarez M.
Eur.
J. Org. Chem.
2007,
1921
<A NAME="RF22908SS-12">12 </A>
Li CC.
Xie ZX.
Zhang YD.
Chen JH.
Yang Z.
J. Org.
Chem.
2003,
68:
8500
<A NAME="RF22908SS-13">13 </A>
Bew SP.
Knight DW.
Chem. Commun.
1996,
1007
<A NAME="RF22908SS-14">14 </A>
McDonald C.
Holcomb H.
Kennedy K.
Kirkpatrick E.
Leathers T.
Vanemon P.
J. Org. Chem.
1989,
54:
1213 ; and references cited therein
<A NAME="RF22908SS-15">15 </A>
The X-ray data for 17 have
been deposited at CCDC under the number CCDC701406.