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DOI: 10.1055/s-2004-817763
A Short Enantioselective Synthesis of Protected l-3-Hydroxy-4-methoxy-5-methyl Phenylalanine and its Corresponding Aldehyde - A Common Subunit of Ecteinascidin-743, Safracin and Congeners
Publication History
Publication Date:
10 February 2004 (online)
Abstract
An asymmetric synthesis of appropriately protected l-3-hydroxy-4-methoxy-5-methyl phenylalanine from 3-methyl-catechol is described featuring a key enantioselective alkylation step.
Key words
amino acid - Ecteinascidin 743 - phase transfer catalyst - glycine template - l-DOPA derivative.
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1a
Rinehart KL.Holt TG.Fregeau NL.Stroh JG.Shield LS.Seigler DS. J. Nat. Prod. 1990, 53: 771 -
1b
Wright AE.Forleo DA.Gunawardana GP.Gunasekera SP.Koehn FE.McConnell OJ. J. Org. Chem. 1990, 55: 4508 -
1c
Suwanborirux K.Charupant K.Amnuoypol S.Pummangura S.Kubo A.Saito N. J. Nat. Prod. 2002, 65: 935 -
2a
Ikeda Y.Shimada Y.Honjo K.Okumoto T.Munakata T. J. Antibiot. 1983, 36: 1290 -
2b
Saito N.Harada S.Yamashita M.Saito T.Yamaguchi Y.Kubo A. Tetrahedron 1995, 51: 8213 - 3 For a recent review, see:
Scott JD.Williams RM. Chem. Rev. 2002, 102: 1669 -
4a
Corey EJ.Gin DY.Kania RS. J. Am. Chem. Soc. 1996, 118: 9202 -
4b
Corey EJ.Gin DY. Tetrahedron Lett. 1996, 37: 7163 -
5a
Endo A.Yanagisawa A.Abe M.Tohma S.Kan T.Fukuyama T. J. Am. Chem. Soc. 2002, 124: 2545 -
5b
Endo A.Kann T.Fukuyama T. Synlett 1999, 7: 1103 - 6
Cuevas C.Pérez M.Martin MJ.Chicharro JL.Fernandez-Rivas C.Flores M.Francesch A.Gallego P.Zarzuelo M.De La Calle F.Garcia J.Polanco C.Rodriguez I.Manzanares I. Org. Lett. 2000, 2: 2545 -
7a
Saito N.Kamayachi H.Tachi M.Kubo A. Heterocycles 1999, 51: 9 -
7b
Saito N.Tachi M.Seki R.Kamayachi H.Kubo A. Chem. Pharm. Bull. 2000, 48: 1549 -
8a
Zhou B.Edmondson S.Padron J.Danishefsky SJ. Tetrahedron Lett. 2000, 41: 2039 -
8b
Zhou B.Guo J.Danishefsky SJ. Tetrahedron Lett. 2000, 41: 2043 -
8c
Zhou B.Guo J.Danishefsky SJ. Org. Lett. 2002, 4: 43 -
9a
Jin W.Williams RM. Tetrahedron Lett. 2003, 44: 4635 -
9b
Jin W.Metobo S.Williams RM. Org. Lett. 2003, 5: 2095 - 10
De Paolis M.Chiaroni A.Zhu J. Chem. Commun. 2003, 2896 - 11
Corey EJ.Xu F.Noe MC. J. Am. Chem. Soc. 1997, 119: 12414 - 12
Lygo B.Wainwright PG. Tetrahedron Lett. 1997, 38: 8595 - 13 For an earlier contribution, see:
O’Donnell MJ.Bennett WD. J. Am. Chem. Soc. 1989, 111: 2353 - 14
Sinhababu AK.Gosh AK.Borchardt RT. J. Med. Chem. 1985, 28: 1273 -
16a
Trost BM.Bunt RC.Pulley SR. J. Org. Chem. 1994, 59: 4202 -
16b
Helmchen G.Sauber K. Tetrahedron Lett. 1972, 3873
References
Compound 6. [α]D
23 +13 (c = 0.8, CHCl3). IR (CHCl3): 3382, 3034, 2981, 2938, 1725, 1598, 1495, 1370, 1293, 1218, 1178 cm-1. 1H NMR (250 MHz, CDCl3, 293 K): δ = 7.76 (d, J = 7.6 Hz, 2 H), 7.32 (d, J = 7.5 Hz, 2 H), 6.90 (br s, 1 H), 6.79 (br s, 1 H), 3.67 (s, 3 H), 3.48 (dd, J = 7.3, 5.5 Hz, 1 H), 2.88 (dd, J = 13.7, 5.5 Hz, 1 H), 2.67 (dd, J = 13.7, 7.3 Hz, 1 H), 2.44 (s, 3 H), 2.19 (s, 3 H), 1.42 (s, 9 H). 13C NMR (75 MHz, CDCl3, 293 K): 174.0, 149.3, 145.1, 142.2, 133.1, 132.8, 130.4, 129.5, 129.2, 128.5, 128.4, 121.8, 81.2, 60.5, 56.0, 40.2, 28.1, 27.9, 21.6, 15.9. MS (ESI+): m/z = 436.2 [M + H]+, 458.3 [M + Na]+, 474.2 [M + K]+. HRMS (ESI+): m/z [M + H+] calcd for C22H30O6S: 436.1794; found: 436.1789.
Compound 7. [α]D
23 +22 (c = 1, CHCl3). IR (CHCl3): 3426, 3024, 2933, 2830, 1716, 1590, 1496, 1343, 1232, 1087, 1007 cm-1. 1H NMR (300 MHz, CDCl3, 293 K): 9.52 (s, 1 H), 6.56 (m, 2 H), 5.96 (ddd, J = 17.7, 12.5, 7.2 Hz, 1 H), 5.82 (m, 1 H), 5.33 (ddt, J = 16.8, 1.7, 1.6 Hz, 1 H), 5.17 (m, 4 H), 4.47 (m, 4 H), 4.46 (m, 1 H), 3.80 (s, 3 H), 2.98 (dd, J = 14.0, 6.5 Hz, 1 H), 2.89 (dd, J = 14.0, 6.8 Hz, 1 H), 2.21 (s, 3 H). 13C NMR (75 MHz, CDCl3, 293 K): 199.2, 155.8, 151.6, 146.7, 133.2, 132.5, 132.3, 130.6, 123.8, 118.0, 117.5, 112.7, 69.4, 65.9, 60.9, 60.1, 35.2, 15.9. MS (ESI+): m/z = 334.2 [M + H]+.