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6. (a) Chloramphenicol has been assigned as a generic name to the compound D-(−)-threo-N-(1,10-dihydroxy-1-p-
nitrophenylisopropyl)-dichloroacetamide for which Parke, Davis and Co. has adopted ‘Chloromycetin’ as its trademark.
(b) Bartz, Q. R. J. Biol. Chem. 1948, 172, 445.
7. (a) Controulis, J.; Rebstock, M. C.; Crooks Jr., H. M. J. Am. Chem. Soc. 1949, 71, 2463. (b) Rao, A. V. R. et al. J. Chem.
Soc., Chem. Commun. 1992, 11, 859. (c) Hazra, B. G. et al. Syn. Comm. 1997, 27(11), 1857.
8. (a) The absolute configuration was assumed from the results in Ref. 4 and confirmed later by comparison of the optical
rotation with that reported for chloramphenicol (2). (b) The enantiomeric purity (ee) was determined by HPLC analysis
using a Daicel Chiralcel OJ column. (c) The diastereoselectivity was determined by 1H NMR analysis at 500 MHz in CDCl3
solution.
9. Keeping the reaction mixture at 40°C was crucial for good yields of the azide 6.
10. Lambert, P. H.; Vaultier, M.; Carrie, R. J. Chem. Soc., Chem. Commun. 1982, 1224.
11. Dolbier Jr., W. R.; Lee, S. K.; Phanstiel IV., O. Tetrahedron 1991, 47, 2065.
12. Hakomori, S. Handbook of Lipid Research, Vol. 3, Sphingolipid Biochemistry; Kanfer, J. N.; Hakomori, S., Eds.; Plenum
Press: New York, 1983; p. 6.
13. (a) Kozikowski, A. P.; Wu, J.-P. Tetrahedron Lett. 1990, 31, 4309. (b) Byun, H.; Erukulla, R. K.; Bittman, R. J. Org. Chem.
1994, 59, 6495.
14. (a) Li, S.; Wilson, W. K.; Schroepfer Jr., G. J. J. Lipid Research 1999, 40, 117. (b) Herdewijin, P.; De Jonghe, S.; Van
Overmeire, I.; Gunst, J.; De Brunyn, A.; Hendrix, C.; Van Calenbergh, S.; Busson, R.; De Keukeleire, D.; Phillipe, J. Bioorg.
Med. Chem. Lett. 1999, 9, 3159, 3175. (c) Kokotos, G. Pardrón, J. M.; Martin, V. S.; Hadjipavlou-Litina, D.; Noula, C.;
Constantinou-Kokotou, V.; Peters, G. J. Bioorg. Med. Chem. Lett. 1999, 9, 821. (d) Murakami, T.; Taguchi, K. Tetrahedron,
1999, 55, 989. (e) He, L.; Byun, H.-P.; Smit, J.; Wilschut, J.; Bittman, R. J. Am. Chem. Soc. 1999, 121, 3897. (f) Ruan, F.;
Yamamura, S.; Hakomori, S.; Igarashi, Y. Tetrahedron Lett. 1995, 36, 6615.
15. The diastereoselectivity was determined by 1H NMR analysis at 500 MHz in CDCl3 solution. The enantiomeric purity (ee)
was determined later from its derivative because 10 is readily converted into the corresponding α,β-epoxy ester under basic
conditions. The absolute configuration was assumed from the results in Ref. 4 and confirmed later by comparison of the
optical rotation with that reported for the final product, acetyl (D)-threo-sphingosine.
1
16. The enantiomeric purity of the alcohol 14 was confirmed by its conversion to (R)-(+)-MTPA ester followed by H NMR
analysis at 500 MHz. There was no detectable amount of the other enantiomer.
17. Tkaczuk, P.; Thornton, E. R. J. Org. Chem. 1981, 46, 4393.
18. This research was assisted financially by a grant from the National Institutes of Health.