4,6-Dimethoxy-3,7-dimethylcoumarin from Colchicum decaisnei. Total synthesis by carbamoyl Baker-Venkataraman rearrangement and structural revision to isoeugenetin methyl ether

Tetrahedron Letters

Volumn 39, Issue 28, 1998, Pages 4999-5002

  Kalinin, Alexey V ^a   Snieckus, Victor ^a  

^a UNIVERSITY OF WATERLOO   (Canada)

Author keywords

[No Author keywords available]

Indexed keywords

4,6 DIMETHOXY 3,7 DIMETHYLCOUMARIN; COUMARIN DERIVATIVE; ISOEUGENETIN METHYL ETHER; UNCLASSIFIED DRUG;

ARTICLE; COLCHICUM; COUPLING FACTOR; DRUG ISOLATION; DRUG SYNTHESIS; GENE REARRANGEMENT; NONHUMAN; NUCLEAR MAGNETIC RESONANCE; SPECTROSCOPY; STRUCTURE ANALYSIS;

COLCHICUM; EUGENIA; SYZYGIUM AROMATICUM;

EID: 0032500062     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(98)00978-2     Document Type: Article

References (18)

1. 1. Kalinin, A. V.; da Silva A. J. M.; Lopes, C. C.; Lopes, R. S. C.; Snieckus, V. Tetrahedron Lett. 1998, 39, 4995-4998.
2. 2. Estevez-Braun, A.; Gonzalez, A. G. Nat. Prod. Repts. 1997, 14, 465-475.
3. 3 a) Tabakovic, I.; Tabakovic, K.; Gaon, I. Org. Prep. Proc. Int. 1997, 29, 223-226 and refs cited therein;
4. b) Suzuki, E.; Katsuragawa, B.; Inoue, S. Synthesis 1978, 144-146 and refs cited therein;
5. c) Bohlmann, F.; Steinmeyer, A. Tetrahedron Lett. 1986, 27, 5359-5362.
6. 4. Al-Tel, T. H.; Zarga, M. H. A.; Sabri, S. S.; Feroz, M.; Fatima, N.; Shah, Z.; Atta-ur-Rahman Phytochemistry 1991, 30, 3081-3086.
7. 5. a) Schmid, H.; Bolleter, A. Helv. Chim. Acta 1949, 32, 1358-1360;
8. b) Schmid, H.; Bolleter, A. Helv. Chim. Acta 1950, 33, 917-922.
9. 6. Knochel, P.; Singer, R. D. Chem. Rev. 1993, 93, 2117-2188;
10. Erdik, E. Tetrahedron 1992, 48, 9577-9648.
11. 7. This route was chosen in lieu of a classical synthesis of the phenol corresponding to 5 by a terminal Baeyer-Villiger oxidation (see, Rathore, R.; Kochi, J. K. J. Org. Chem. 1995, 60, 7479-7490) in order to provide greater scope for substituent variation in the overall methodology for coumarins. Furthermore, experiments of metal-halogen exchange (n-BuLi/-78°C) and MeI or MeOTf quench on 4 led to complex mixtures containing minor amounts of 5.
12. 3) δ 6.98 (d, 1H, J = 8.6 Hz). 6.81 (d, 1H, J = 8.6 Hz), 3.82 (s, 3H), 3.56-3.30 (m, 4H), 2.71 (q, 2H, J = 7.2 Hz), 2.07 (s, 3H), 1.30-1.05 (m, 9H).
13. 9. Snieckus, V. Chem. Rev. 1990, 90, 879-933.
14. 4: C, 66.65; H, 6.02. Found: C, 66.49; H, 6.10.
15. 11. Eguchi, S. Org. Mass Spectrom. 1979, 14, 345-349.
16. 12. Tada, A.; Saiton, T.; Shoji, J. Chem. Pharm. Bull. 1980, 28, 2487-2493.
17. 4; 234.0892. Found 234.0888.
18. 14. All new compounds show analytical and spectra (IR, NMR, HRMS) data consistent with the given structures.