Claims
- 1. A process for preparing compounds of Formulas 3a' and 3b' ##STR26## wherein Q and T can be the same or different amino protecting groups, p is 1 or 2, R.sup.1 is phenyl or alkyl substituted phenyl, n is 1 to 3; comprising the steps of:
- (a) forming a trianion of a compound of Formula iv using a strong base ##STR27## wherein T, Q and n are as defined above and R.sup.2 refers to alkyl; (b) reacting the trianion of a compound of Formula iv with a silylimine of Formula v ##STR28## wherein R.sup.1 and p are as defined above and R.sup.3, R.sup.4 and R.sup.5 can independently be alkyl, phenyl or alkyl substituted phenyl to afford a compound of Formula vi ##STR29## in which T, Q, n, p, R.sup.1, R.sup.4, R.sup.3 and R.sup.5 are as defined previously;
- (c) hydrolyzing the nitrogen silicone bond of a compound of Formula vi to afford a compound of the formula 3, and ##STR30## (d) separating the cis and trans isomers of a compound of Formula 3 to produce compounds of Formulas 3a' and 3b'.
- 2. The process of claim 1 in which T and Q are each independently t-butoxycarbonyl or phenylmethoxycarbonyl; n is 1 or 2; p is 1; R.sup.1 is phenyl, R.sup.2 is methyl; and R.sup.3, R.sup.4 and R.sup.5 are methyl.
CROSS REFERENCE TO RELATED APPLICATION
This application is a divisional application of U.S. Ser. No. 07/957,233 filed Oct. 6, 1992, U.S. Pat. No. 5,250,677; which is a divisional of U.S. Ser. No. 07/833,876 filed Feb. 11, 1992, now U.S. Pat. No. 5,175,283; which is a divisional of U.S. Ser. No. 07/696,641 filed on May 7, 1991, now U.S. Pat. No. 5,110,812; which is a divisional of U.S. Ser. No. 07/533,270 filed Jun. 4, 1990, now U.S. Pat. No. 5,037,819.
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Divisions (4)
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Number |
Date |
Country |
Parent |
957233 |
Oct 1992 |
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Parent |
833876 |
Feb 1992 |
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Parent |
696641 |
May 1991 |
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Parent |
533270 |
Jun 1990 |
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