Reductive cleavage of resin bound arylsulfonates

Tetrahedron Letters

Volumn 39, Issue 22, 1998, Pages 3651-3654

  Jin, Shujuan ^a   Holub, David P ^a   Wustrow, David J ^a  

^a PFIZER INC   (United States)

Author keywords

Reduction; Solid Phase Synthesis; Sulfonic Acid and Derivatives

Indexed keywords

ARYLSULFONIC ACID DERIVATIVE;

ARTICLE; BINDING AFFINITY; CHLORINATION; DNA CLEAVAGE; DRUG SYNTHESIS; NONHUMAN; PROTEIN DEGRADATION; PROTON NUCLEAR MAGNETIC RESONANCE; REACTION ANALYSIS; SOLID PHASE EXTRACTION;

EID: 0032575176     PISSN: 00404039     EISSN: None     Source Type: Journal    
DOI: 10.1016/S0040-4039(98)00640-6     Document Type: Article

References (28)

1. 1. Chenera, B.; Finkelstein, J. A.; Veber, D. F. J. Am. Chem. Soc. 1995. 117, 11999-12000.
2. 2. Kenner, G. W.; McDermott, J. R.; Sheppard, R. C. J. Chem. Soc., Chem. Commun. 1971, 636-637.
3. 3. Backes, B. J.; Ellman, J. A. J. Am. Chem. Soc. 1994, 116, 11171-11172.
4. 4. Backes, B. J.; Virgilio, A. A.; Ellman, J. A. J. Am. Chem. Soc. 1996, 118, 3055-3056.
5. 5. Beaver, K. A.; Siegmund, A. C.; Spear, K. L. Tetrahedron Lett. 1996, 37, 1145-1148.
6. 6. Hunt, J. A.; Roush, W. R. J. Am. Chem. Soc. 1996, 118, 9998-9999.
7. 7. Wang, Y.; Wilson, S. R. Tetrahedron Lett. 1997, 38, 4021-4024.
8. 8. Plunkett, M. J.; Ellman, J. A. J. Org. Chem. 1995, 60, 6006-6007.
9. 9. Plunkett, M. J.; Ellman, J. A. J. Org. Chem. 1997, 62, 2885-2893.
10. 10. Cabri, W.; De Bernardinis, S.; Francalanci, F.; Penco, S. J. Org. Chem. 1990, 55, 350-353.
11. 11. Chlorosulfonic acid resin is commercially available however this resin is macroreticular in nature meaning it does not swell as a normal resin would in organic solvents.
12. 12. Kamahori, K.; Tada, S.; Ito, K.; Itsuno, S. Tetrahedron Asymmetry 1995, 6, 2547-2555.
13. 13C NMR and mass spectral data.
14. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
15. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
16. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
17. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
18. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
19. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
20. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
21. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
22. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
23. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
24. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
25. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
26. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
27. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.
28. 14. Compound 8a is commercially available. The following compounds have previously been described in the literature: 8d, Tsai, Y-M.; Cherng, C-D. Tetrahedron Lett. 1991, 32, 3515-3518; 8e, Pincock, J. A.; Pincock, A. L.; Fox, M. A. Tetrahedron, 1985, 41, 4107-4117. Ishihara, K.; Kubota, M.; Kurihara, H.; Yamamoto, H. J. Org. Chem. 1996, 61, 4560-4567; 8h, Balfe, M. P.; Irwin, M. Kenyon, J. J. Chem. Soc. 1941, 312-316; 9a, see Vaughan, W. R.; Carlson, R. D. J. Am. Chem. Soc. 1962, 84, 769-774; 9b, Barluenga, J.; Montserrat, J. M.; Florez, J. J. Org. Chem. 1993, 58, 5976-5980; Gray, N. M.; Cheng, B. K.; Mick, S. J.; Lair, C. M.; Contreras, P. C. J. Med. Chem. 1989, 32, 1242-1248; 9c, Yokomatsu, T.; Arakawa, A.; Shibuya, S. J. Org. Chem. 1994, 59, 3506-3508; 9d, Heusler, K. HeLv. Chim. Acta. 1972, 55, 388-408. Wang, W. B.; Roskamp, E. J. J. Org. Chem. 1992, 57, 6101-6103; 9e, Braun, J. V.; Beschke, E. Chem. Ber. 1906, 39, 4119-4125; 9g, Baltzly, R.; Buck, J. S.; Lorz, E.; Schon, W. J. Am. Chem. Soc. 1944, 66, 263-266; Craig, J. C. J. Chem. Soc. 1959, 3634-3635; 9h, see Hauser, C. R.; Walker, JR., H. G. J. Am. Chem. Soc. 1947, 69, 295-297; Micovic, V. M.; Mihailovic, M. LJ. J. Org. Chem. 1953, 18, 1190-1197.