Claims
- 1. The process for producing the compounds having the structure ##STR7## wherein R.sup.1 is hydrogen, lower alkyl containing 1 to 4 carbon atoms or halogen, and the pharmaceutically acceptable salts thereof which comprises
- (a) successively halogenating in the presence of t-butyllithium and tetramethylenediamine and hydrolyzing with a strong base the compound of structure ##STR8## wherein R.sup.1 is as defined above to produce the amine of structure ##STR9## wherein R.sup.1 is as defined and X is bromine or iodine (b) reacting said amine successively with HNO.sub.2 in aqueous HCl and SnCl.sub.2 in aqueous HCl to produce the hydrazine of structure ##STR10## wherein R.sup.1 and X are as defined above (c) reacting said hydrazine with dihydrofuran to produce the corresponding hydrazone ##STR11## wherein R.sup.1 and X are as defined above and in the presence of zinc chloride converting the hydrazone to the corresponding tryptophol of structure ##STR12## wherein R.sup.1 and X are as defined above (d) cyclizing said tryptophol with methyl 3-methoxy-2-pentenoate in the presence of boron trifluoride etherate to produce the indole of structure ##STR13## wherein R.sup.1 and X are as defined above (e) reacting said indole with tributylallyltin in the presence of tetrakis(triphenylphosphine)palladium in a sealed container under an inert atmosphere to produce the ester of structure ##STR14## wherein R.sup.1 is as defined above (f) hydrolyzing said ester with a strong base to produce the desired compound of structure (I) and optionally converting said compound to a pharmaceutically acceptable salt.
- 2. The process according to claim 1 for brominating the compound of structure ##STR15## in the presence of t-butyllithium in hydrocarbon solvent and tetramethylenediamine in THF at about -78.degree. C. to produce the compound of structure ##STR16##
- 3. The process according to claim 1 for alkylating the compound of structure ##STR17## wherein R.sup.2 is hydrogen or lower alkyl containing 1 to 4 carbon atoms, with tributylallyltin in the presence of tetrakis(triphenylphosphine)palladium in a sealed container under N.sub.2 at about 80.degree. to 120.degree. C. to produce the compound of structure ##STR18## wherein R.sup.2 is as defined above.
Parent Case Info
This is a division of application Ser. No. 117,775, filed Nov. 5, 1987, issued 11/15/88 as U.S. Pat. No. 4,785,015.
US Referenced Citations (1)
Number |
Name |
Date |
Kind |
3939178 |
Demerson |
Feb 1976 |
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Foreign Referenced Citations (1)
Number |
Date |
Country |
548022 |
Oct 1985 |
ESX |
Divisions (1)
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Number |
Date |
Country |
Parent |
117775 |
Nov 1987 |
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