The stereoselective ring contraction of a pyranosylated indolocarbazole. A biosynthetic link between K252a and staurosporine?

Tetrahedron Letters

Volumn 37, Issue 23, 1996, Pages 3929-3930

  Stoltz, Brian M ^a   Wood, John L ^a  

^a YALE UNIVERSITY   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

ENZYME INHIBITOR; K 252A;

ARTICLE; CARBOHYDRATE SYNTHESIS; DRUG SYNTHESIS; REACTION ANALYSIS; STEREOCHEMISTRY;

EID: 0030043992     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/0040-4039(96)00717-4     Document Type: Article

References (10)

1. Wood, J. L.; Stoltz, B. M.; Dietrich, H.-J. J. Am. Chem. Soc. 1995, 117, 10413.
2. For a review, see: Gribble, G.; Berthel, S. Studies in Natural Products Chemistry, Vol. 12; Elsevier Science Publishers: New York, 1993; pp 365-409 and references therein.
3. Stoltz, B. M.; Wood, J. L. Tetrahedron Lett. 1995, 36, 8543. This ring expansion protocol has been successfully extended to systems containing the fully elaborated aglycon (Stoltz, B. M.; Goodman, S. N.; Wood, J. L. unpublished results).
4. Fredenhagen, A.; Peter, H. H. Tetrahedron 1996, 52, 1235. In addition, these authors report a ring contractive Beckmann rearrangement that stereoselectively produces an amino analog of K252a.
5. Takahashi, H.; Osada, H.; Uramoto, M.; Isono, K. J. Antibiotics 1990, 43, 168.
6. (a) Tanida, S.; Takizawa, M.; Takahashi, T.; Tsubotani, S.; Harada, S. J. Antibiotics 1989, 42, 1619.
7. (b) Tsubotani, S.; Tanida, S.; Harada, S. Tetrahedron 1991, 47, 3565.
8. Cai, Y.; Fredenhagen, A.; Hug, P.; Peter, H. H. J. Antibiotics 1995, 48, 143.
9. Vowinkel, E. Chem. Ber. 1966, 99, 1479. Although this method was reported for the preparation of aryl ethers and failure was anticipated, the thought of what appeared a trivial alkylation thwarting the elegant ring expansion approach led us to explore the remotest of possibilities.
10. 2 (14 mL), and the mixture warmed to reflux for 6 h. Solvent was removed in vacuo and the resulting residue subjected to silica gel chromatography (2:1, hexane:ethyl acetate) to afford 6 (102 mg, 0.25 mmol, 95%) as a colorless solid (mp 235-239 °C).