Claims
- 1. A process for the preparation of a compound which has the formula ##STR27## wherein R is alkyl of 1 to 4 carbon atoms and R.sub.1 is methyl or ethyl and R.sub.4 is alkyl of 1 to 4 carbon atoms comprising reacting a compound of the formula ##STR28## wherein R and R.sub.1 have the above definition with a ketone protecting reactant to obtain a compound of the formula ##STR29## wherein R is a ketal, enamine or enol ether and the dotted line is a double bond when B is an enamine or enol ether, reacting the latter with an oxidation agent selected from the group consisting of pyridinium dichromate, sulfochromic acid solution, pyridinium chlorochormate, chromium trioxide in pyridinium, aluminum isopropoxide and aluminum tertiary butoxide to obtain a compound of the formula ##STR30## treating the latter with an iodide of the formula R.sub.4 I in the presence of a strong base to form a compound of the formula ##STR31## reacting the latter with a reducing agent selected from the group consisting of lithium aluminum hydride, sodium borohydride, potassium borohydride, and lithium borohydride to obtain a compound of the formula ##STR32## and treating the latter to remove the ketone protecting group to obtain the compound of formula I.sub.B.
- 2. A process for the preparation of a compound which has the formula ##STR33## wherein R is alkyl of 1 to 4 carbon atoms, R.sub.1 is methyl or ethyl, R.sub.3 is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms and alkenyl and alkynyl of 2 to 4 carbon atoms, R.sub.4 is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms, with the proviso that when R.sub.4 is hydrogen, R and R.sub.1 are not methyl when R.sub.3 is ethyl comprising reacting a compound of the formula ##STR34## wherein B, R, R.sub.1, R.sub.4 and the dotted line have the above definition with a compound of the formula R.sub.3 -D wherein R.sub.3 has the above definition and D is lithium or Mg-Hal and Hal is a halogen to obtain a compound of the formula ##STR35## and treating the latter to remove the ketone protecting group to obtain the compound of formula I.sub.C.
- 3. A process for the preparation of a compound which has the formula ##STR36## wherein R is alkyl 1 to 4 carbon atoms, R.sub.1 is methyl or ethyl, R.sub.3 is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms and alkenyl and alkynyl of 2 to 4 carbon atoms, R.sub.4 is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms, comprising reacting a compound of the formula ##STR37## with a hydroxyl protecting reactant to obtain a compound of the formula ##STR38## wherein A' is a hydroxyl protecting group, reacting the latter with a brominating agent to obtain a compound of the formula ##STR39## and treating the latter with a dehydrobromination agent and an agent to remove the hydroxyl protecting group to obtain a compound of formula I.sub.D.
- 4. A process for the preparation of a compound which has the formula ##STR40## wherein R is alkyl of 1 to 4 carbon atoms and R.sub.1 is methyl or ethyl, R.sub.3 is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms and alkenyl and alkynyl of 2 to 4 carbon atoms, R.sub.4 is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms with the proviso that when R.sub.4 is hydrogen, (a) R and R.sub.1 are not methyl when R.sub.3 is hydrogen, methyl, ethyl, propargyl or isobutenyl or (b) when R.sub.3 is hydrogen, R is not methyl and R.sub.1 is ethyl or R.sub.1 is methyl and R is not ethyl comprises reacting a compound of the formula ##STR41## with a hydrogenation agent to obtain the compound of formula I.sub.E.sup.'.
- 5. A process for the preparation of a compound which has the formula ##STR42## wherein R is alkyl of 1 to 4 carbon atoms, R.sub.1 is methyl or ethyl, R.sub.3 is selected from the group consisting of hydrogen, alkyl of 1 to 4 carbon atoms and alkenyl and alkynyl of 2 to 4 carbon atoms, R.sub.4 is selected from the group consisting of hydrogen and alkyl of 1 to 4 carbon atoms and R.sub.2.sup.' is R.sub.2 other than hydrogen excluding the compounds wherein R.sub.4 is hydrogen, the dotted line in the 4(5)-position is not a double bond and the dotted line in the 5a(6)-position is a double bond and (a) R is methyl, R.sub.3 is hydrogen and (i) R.sub.2.sup.' is acetyl, tert.-butyl or benzoyl and R.sub.1 is methyl or (ii) R.sub.2.sup.' is tert.-butyl and R.sub.1 is ethyl, (b) R is ethyl or propyl, R.sub.3 is hydrogen, R.sub.2.sup.' is benzoyl and R.sub.1 is methyl and excluding also the compounds wherein R.sub.4 is hydrogen and the dotted lines do not indicate a double bond and (a) R.sub.1 and R are methyl, R.sub.3 is hydrogen and R.sub.2.sup.' is acetyl or benzoyl, (b) R and R.sub.1 are methyl, R.sub.2.sup.' is methoxymethyl and R.sub.3 is hydrogen and (c) R, R.sub.1 and R.sub.3 are methyl and R.sub.2.sup.' is acetyl comprising either reacting a compound of the formula ##STR43## with a compound of the formula R.sub.2.sup.' -E wherein E is a functional group residue and R.sub.2.sup.' has the above definition to obtain the corresponding compound of formula I.sub.F.sup.' or reacting a compound of the formula ##STR44## wherein B has the above definition with a compound of the formula R.sub.2.sup.' -E wherein R.sub.2.sup.' and E have the above definition to obtain a compound of the formula ##STR45## and treating the latter to remove the ketone protecting group to obtain a compound of formula I.sub.F.sup.' wherein there is no double bond in the 4(5)-position.
Priority Claims (1)
Number |
Date |
Country |
Kind |
81 04630 |
Feb 1981 |
FRX |
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Parent Case Info
This is a division of U.S. patent application Ser. No. 855,905 filed Apr. 24, 1986 U.S. Pat. No. 4,849,454 which is a division of Ser. No. 06/543,315, Oct. 19, 1983, U.S. Pat. No. 4,607,054, which is a continuation-in-part of Ser. No. 06/350,151, Feb. 19, 1982, U.S. Pat. No. 4,466,971.
US Referenced Citations (3)
Number |
Name |
Date |
Kind |
3496199 |
Uskokovic |
Feb 1970 |
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3499912 |
Uskokovic et al. |
Mar 1970 |
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3956316 |
Uskokovic et al. |
May 1976 |
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Divisions (2)
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Number |
Date |
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Parent |
855905 |
Apr 1986 |
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Parent |
543315 |
Oct 1983 |
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Continuation in Parts (1)
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Number |
Date |
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Parent |
350151 |
Feb 1982 |
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