The present application relates methods for treating a depressive symptom comprising administering an effective amount of a opioid receptor agonist or a pharmaceutically acceptable salt thereof to a subject in need thereof. Non-limiting examples of such agonist include the compounds of Formulas I, II, III, and IV, as well as the compounds of Table A.

The present application relates methods for treating a depressive symptom comprising administering an effective amount of a opioid receptor agonist or a pharmaceutically acceptable salt thereof to a subject in need thereof. Non-limiting examples of such agonist include the compounds of Formulas I, II, III, and IV, as well as the compounds of Table A.

This invention relates to opioid ketal compounds of Formula (I), Formula (II), or Formula (III): or a pharmaceutically acceptable salts thereof, wherein R.sub.1 is H or CH.sub.3, R.sub.2 is H or OH, n is 0, 1, 2 or 3, R.sub.3 and R.sub.4 are independently or optionally substituted C.sub.1-C.sub.4 alkyl, or when n is 0, then R.sub.3 and R.sub.4 and the carbon atoms to which they are attached together form six, or seven membered ring, which is optionally mono or disubstituted by C.sub.1-C.sub.4 alkyl. The invention also relates to oxycodone ketal compounds of Formula (IV) or (V): or a pharmaceutically acceptable salts thereof. The invention also relates to the use of such compounds for the treatment, prevention, or amelioration of pain.

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This invention relates to opioid ketal compounds of Formula (I), Formula (II), or Formula (III): or a pharmaceutically acceptable salts thereof, wherein R.sub.1 is H or CH.sub.3, R.sub.2 is H or OH, n is 0, 1, 2 or 3, R.sub.3 and R.sub.4 are independently or optionally substituted C.sub.1-C.sub.4 alkyl, or when n is 0, then R.sub.3 and R.sub.4 and the carbon atoms to which they are attached together form six, or seven membered ring, which is optionally mono or disubstituted by C.sub.1-C.sub.4 alkyl. The invention also relates to oxycodone ketal compounds of Formula (IV) or (V): or a pharmaceutically acceptable salts thereof. The invention also relates to the use of such compounds for the treatment, prevention, or amelioration of pain.

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The present application relates methods for treating a depressive symptom comprising administering an effective amount of a opioid receptor agonist or a pharmaceutically acceptable salt thereof to a subject in need thereof. Non-limiting examples of such agonist include the compounds of Formulas I, II, III, and IV, as well as the compounds of Table A.

The present application relates methods for treating a depressive symptom comprising administering an effective amount of a opioid receptor agonist or a pharmaceutically acceptable salt thereof to a subject in need thereof. Non-limiting examples of such agonist include the compounds of Formulas I, II, III, and IV, as well as the compounds of Table A.

The present application relates methods for treating a depressive symptom comprising administering an effective amount of a opioid receptor agonist or a pharmaceutically acceptable salt thereof to a subject in need thereof. Non-limiting examples of such agonist include the compounds of Formulas I, II, III, and IV, as well as the compounds of Table A.

The present application relates methods for treating a depressive symptom comprising administering an effective amount of a opioid receptor agonist or a pharmaceutically acceptable salt thereof to a subject in need thereof. Non-limiting examples of such agonist include the compounds of Formulas I, II, III, and IV, as well as the compounds of Table A.

In one aspect, the invention provides compounds of Formula I: (I) and pharmaceutically acceptable salts and solvates thereof, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, Y, Z.sub.a are defined as set forth in the disclosure. The invention also provides compounds of any one of Formulae II to VII, IA to IC, and IIA to IIC, and pharmaceutically acceptable salts and solvates thereof. Other aspects of the invention include the use of compounds of Formulae I to VII, IA to IC, and IIA to IIC, and pharmaceutically acceptable salts and solvates thereof for the treatment of disorders responsive to modulation of one or more opioid receptors. In certain embodiments, the Compounds of the Invention are useful for treating pain. ##STR00001##

The present invention relates to a method of preparing a compound of Formula II-a or Formula II-b, wherein R.sup.I represents hydrogen or a linear, branched and/or cyclic alkyl or alkenyl group having 1 to 10 carbon atoms;

R.sup.II represents a linear, branched and/or cyclic alkyl or alkenyl group having 1 to 10 carbon atoms; R.sup.III represents hydrogen or a linear, branched and/or cyclic alkyl or alkenyl group having 1 to 10 carbon atoms or a linear, branched and/or cyclic alkoxy group having 1 to 10 carbon atoms; R.sup.IV represents hydrogen or a linear, branched and/or cyclic alkyl group having 1 to 10 carbon atoms or an optionally substituted aryl or alkylaryl group having 6 to 40 carbon atom or acetyl or silyl or a protective group; and R.sup.V represents hydrogen or a methyl group; wherein R.sup.I and R.sup.II are different from each other.

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