The present invention relates to Spirocyclic Heterocycle Compounds of Formula (I): (I) and pharmaceutically acceptable salts thereof, wherein A, B, X, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are as defined herein. The present invention also relates to compositions comprising at least one Spirocyclic Heterocycle Compound, and methods of using the Spirocyclic Heterocycle Compounds for treating or preventing HIV infection in a subject.

##STR00001##

The present invention relates to Spirocyclic Heterocycle Compounds of Formula (I): (I) and pharmaceutically acceptable salts thereof, wherein A, B, X, R.sup.1, R.sup.2, R.sup.3 and R.sup.4 are as defined herein. The present invention also relates to compositions comprising at least one Spirocyclic Heterocycle Compound, and methods of using the Spirocyclic Heterocycle Compounds for treating or preventing HIV infection in a subject.

##STR00001##

The present invention relates to compound of Formula I or a pharmaceutically acceptable salt thereof

##STR00001##

wherein R.sup.1 is

##STR00002##

where the squiggly line indicates the point of attachment to the rest of the molecule;
R.sup.2 is F or

##STR00003##

where the squiggly line indicates the point of attachment to the rest of the molecule;
R.sup.3 is H or CH.sub.3;
Z is O or is absent; and
R.sup.4 is —OC.sub.1-3alkyl, C.sub.1-30alkyl, or —N(CH.sub.3).sub.2.

The present invention relates to compound of Formula I or a pharmaceutically acceptable salt thereof

##STR00001##

wherein R.sup.1 is

##STR00002##

where the squiggly line indicates the point of attachment to the rest of the molecule;
R.sup.2 is F or

##STR00003##

where the squiggly line indicates the point of attachment to the rest of the molecule;
R.sup.3 is H or CH.sub.3;
Z is O or is absent; and
R.sup.4 is —OC.sub.1-3alkyl, C.sub.1-30alkyl, or —N(CH.sub.3).sub.2.

The present invention relates to compound of Formula I or a pharmaceutically acceptable salt thereof

##STR00001##

wherein R.sup.1 is

##STR00002##

where the squiggly line indicates the point of attachment to the rest of the molecule;
R.sup.2 is F or

##STR00003##

where the squiggly line indicates the point of attachment to the rest of the molecule;
R.sup.3 is H or CH.sub.3;
Z is O or is absent; and
R.sup.4 is —OC.sub.1-3alkyl, C.sub.1-30alkyl, or —N(CH.sub.3).sub.2.

A combination comprising a tricycle compound and use thereof in the preparation of a medicament for treating HBV. The combination is a combination of a compound of formula (I) or a pharmaceutically acceptable salt thereof and any one drug in the following groups a-c: a. a hepatitis B surface antigen inhibitor, b. a reverse transcriptase inhibitor, and c. a hepatitis B surface antigen inhibitor and a reverse transcriptase inhibitor.

##STR00001##

A combination comprising a tricycle compound and use thereof in the preparation of a medicament for treating HBV. The combination is a combination of a compound of formula (I) or a pharmaceutically acceptable salt thereof and any one drug in the following groups a-c: a. a hepatitis B surface antigen inhibitor, b. a reverse transcriptase inhibitor, and c. a hepatitis B surface antigen inhibitor and a reverse transcriptase inhibitor.

##STR00001##

A combination comprising a tricycle compound and use thereof in the preparation of a medicament for treating HBV. The combination is a combination of a compound of formula (I) or a pharmaceutically acceptable salt thereof and any one drug in the following groups a-c: a. a hepatitis B surface antigen inhibitor, b. a reverse transcriptase inhibitor, and c. a hepatitis B surface antigen inhibitor and a reverse transcriptase inhibitor.

##STR00001##

A method of treating cancer comprises administering: (a) a therapeutically effective amount of a compound of Formula (I) or a pharmaceutically acceptable salt thereof; and (b) a therapeutically effective amount of an additional anti-cancer agent, to a subject in need of such treatment, the compound of Formula (I) being:

##STR00001##

where X, R.sub.1, R.sub.2, ring A, L.sub.1, L.sub.2, L.sub.3, and R.sub.5 are as defined in this disclosure.

A method of treating cancer comprises administering: (a) a therapeutically effective amount of a compound of Formula (I) or a pharmaceutically acceptable salt thereof; and (b) a therapeutically effective amount of an additional anti-cancer agent, to a subject in need of such treatment, the compound of Formula (I) being:

##STR00001##

where X, R.sub.1, R.sub.2, ring A, L.sub.1, L.sub.2, L.sub.3, and R.sub.5 are as defined in this disclosure.