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|---|---|---|---|
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| 5041232 | Batal et al. | Aug 1991 | |
| 5045223 | Batal et al. | Sep 1991 | |
| 5047163 | Batal et al. | Sep 1991 | |
| 5755991 | Ghatlia | May 1998 |
| Entry |
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| J. Org. Chem. (1993), 58, pp. 4791-4793. |