Claims
- 1. A compound of the formula ##STR11## wherein R.sub.1 is an acid stable group stable at a pH which is more acidic than pH 2.
- 2. The compound of claim 1 in which R.sub.1 is acid stable at a pH of from 0.5 to 2.
- 3. The compound of claim 1 wherein R.sub.1 is benzyl.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1650/76 |
Feb 1976 |
CHX |
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Parent Case Info
This is a division of application Ser. No. 856,616, filed Dec. 2, 1977, now issued as U.S. Pat. No. 4,148,807 on Apr. 10, 1979, which in turn is a division of application Ser. No. 765,560, filed Feb. 4, 1977, now issued as U.S. Pat. No. 4,079,065 on Mar. 14, 1978.
US Referenced Citations (2)
Number |
Name |
Date |
Kind |
3943151 |
Corey et al. |
Mar 1976 |
|
3952019 |
Peel |
Apr 1976 |
|
Non-Patent Literature Citations (1)
Entry |
Derwent Abstract 45993V/25B02. |
Divisions (2)
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Number |
Date |
Country |
Parent |
856616 |
Dec 1977 |
|
Parent |
765560 |
Feb 1977 |
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