RSS-Feed abonnieren
DOI: 10.1055/s-0029-1219812
Synthesis of Racemic, N-Benzylated Neoechinulin A and Isoneoechinulin A [¹]
Publikationsverlauf
Publikationsdatum:
09. April 2010 (online)
![](https://www.thieme-connect.de/media/synlett/201008/lookinside/thumbnails/10.1055-s-0029-1219812-1.jpg)
Abstract
Two N-benzylated analogues of the antioxidant, radical scavenging, and neuroprotective alkaloid neoechinulin A were prepared. Since, according to SAR studies, stereochemistry does not play an important role, both analogues were prepared in racemic form, using enaminone chemistry.
Key words
N-benzylated alkaloid analogues - neoechinulin A - diketopiperazines - enaminones - 2-isoprenylated - 2-prenylated indoles
The term isoneoechinulin A is proposed by authors of this work and refers to the prenyl group replacing the isoprenyl group in neoechinulin A. This nomenclature is used for naming compound 2.
-
2a
Dossena A.Marchelli R.Pochini A. J. Chem. Soc., Chem. Commun. 1975, 779 -
2b
Casnati G.Pochini P.Ungaro R. Gazz. Chim. Ital. 1973, 103: 141 - 3
Nagasawa H.Isogai A.Ikeda K.Sato S.Murakoshi S.Suzuki A.Tamura S. Agric. Biol. Chem. 1975, 39: 1901 - 4
Yagi R.Doi M. Biosci., Biotechnol., Biochem. 1999, 63: 932 - 5
Li D.-L.Li X.-M.Li T.-G.Dang H.-Y.Wang B.-G. Helv. Chim. Acta 2008, 91: 1888 - 6
Wang X.-N.Tan R.-X.Liu J.-K. J. Antibiot. 2005, 58: 268 - 7
Wang S.Li X.-M.Teuscher F.Li D.-L.Diesel A.Ebel R.Proksch P.Wang B.-G. J. Nat. Prod. 2006, 69: 1622 - 8
Pettit GR.Hogan F.Xu J.-P.Tan R.Nogawa T.Cichacz Z.Pettit RK.Du J.Ye Q.-H.Cragg G.-M.Harald CL.Hoard MS.Goswami A.Searcy J.Tackett L.Doubek DL.Williams L.Hooper JNA.Schmidt JM.Chapuis J.-C.Tackett DN.Craciunescu F. J. Nat. Prod. 2008, 71: 438 -
9a
Nakatsuka S.Miyazaki H.Goto T. Tetrahedron Lett. 1980, 21: 2817 -
9b
Aoki T.Kamisuki S.Kimoto M.Ohnishi K.Takakusagi Y.Kuramochi K.Takeda Y.Nakazaki A.Kuroiwa K.Ohuchi T.Sugawara F.Arai T.Kobayashi S. Synlett 2006, 677 - 10
Li Y.Li X.Kim S.-K.Kang JS.Choi HD.Rho JR.Son BW. Chem. Pharm. Bull. 2004, 52: 375 - 11
Fukuyama N.Takebayashi Y.Hida M.Ishida H.Ichimori H.Nakazawa H. Free Radical Biol. Med. 1997, 22: 771 - 12
Maruyama K.Ohuchi T.Yoshida K.Shibata Y.Sugawara F.Arai T. J. Biochem. 2004, 136: 81 -
13a
Stanovnik B.Svete J. Chem. Rev. 2004, 104: 2433 -
13b
Stanovnik B.Svete J. Synlett 2000, 1077 -
13c
Stanovnik B.Svete J. Targets Heterocycl. Syst. 2000, 4: 105 - 14
Wagger J.Bevk D.Meden A.Svete J.Stanovnik B. Helv. Chim. Acta 2006, 89: 240 -
15a
Wagger J.Grošelj U.Meden A.Svete J.Stanovnik B. Tetrahedron 2008, 64: 2801 -
15b
Wagger J.Svete J.Stanovnik B. Synthesis 2008, 1436 -
16a
Časar Z.Bevk D.Svete J.Stanovnik B. Tetrahedron 2005, 61: 7508 -
16b
Stanovnik B.Svete J. Mini-Rev. Org. Chem. 2005, 2: 211 -
17a
Selič L.Jaške R.Lampiš K.Golič L.Goliš Grdadolnik S.Stanovnik B. Helv. Chim. Acta 2000, 83: 2802 -
17b
Selič L.Stanovnik B. Tetrahedron 2000, 57: 3159 -
17c
Selič L.Rečnik S.Stanovnik B. Heterocycles 2002, 58: 577 -
17d
Jakše R.Krošelj V.Rečnik S.Soršak G.Svete J.Stanovnik B.Golič Grdadolnik S. Z. Naturforsch., B: Chem. Sci. 2002, 57: 453 -
17e
Jakše R.Svete J.Stanovnik B.Golobič A. Tetrahedron 2004, 60: 4601 -
17f
Jakše R.Bevk D.Golobič A.Svete J.Stanovnik B. Z. Naturforsch., B: Chem. Sci. 2006, 61: 413 -
17g
Jakče R.Rečnik S.Golobič A.Golič L.Stanovnik B. Tetrahedron 2001, 57: 8395 -
18a
Kimoto K.Aoki T.Shibata Y.Kamisuku S.Sugawara F.Kuramochi K.Nakazaki A.Kobayashi S.Kuroiwa K.Watanabe N.Arai T. J. Antibiot. 2007, 60: 614 -
18b
Kuramochi K.Ohnishi K.Fujeda S.Nakajima M.Saitoh Y.Watanabe N.Takeuchi T.Nakazaki A.Sugawara F.Arai T.Kobayashi S. Chem. Pharm. Bull. 2008, 56: 1738 -
19a
Wagger J.Golič Grdadolnik S.Gročelj U.Meden A.Stanovnik B.Svete J. Tetrahedron: Asymmetry 2007, 19: 1557 -
19b
Malavašič Č.Wagger J.Stanovnik B.Svete J. Tetrahedron: Asymmetry 2008, 19: 1557 - 20
Depew KM.Danishefsky SJ.Rosen N.Sepp-Lorenzino L. J. Am. Chem. Soc. 1996, 118: 12436 - 21
Kramer GW.Brown HC. J. Organomet. Chem. 1977, 132: 9 - 23
Brennan MR.Erickson KL.Szmalc FS.Tansey MJ.Thornton J.Janice M. Heterocycles 1986, 24: 2879
References and Notes
The term isoneoechinulin A is proposed by authors of this work and refers to the prenyl group replacing the isoprenyl group in neoechinulin A. This nomenclature is used for naming compound 2.
22A crystal structure of isoprenylated analogue 1 was established from monocrystal, but the diffraction data were poor for the isoprenylated region of the molecule; although the X-ray structure obtained unambiguously showed a Z orientation around the exocyclic double bond.