Compounds of Formula I are disclosed and methods of treating viral infections with compositions comprising such compounds.

FIELD OF THE INVENTION

The present invention relates to substituted isoindoline compounds, pharmaceutical compositions, and methods of use thereof for (i) inhibiting HIV replication in a subject infected with HIV, or (ii) treating a subject infected with HIV, by administering such compounds.

BACKGROUND OF THE INVENTION

Human immunodeficiency virus type 1 (HIV-1) leads to the contraction of acquired immune deficiency disease (AIDS). The number of cases of HIV continues to rise, and currently over twenty-five million individuals worldwide suffer from the virus. Presently, long-term suppression of viral replication with antiretroviral drugs is the only option for treating HIV-1 infection. Indeed, the U.S. Food and Drug Administration has approved twenty-five drugs over six different inhibitor classes, which have been shown to greatly increase patient survival and quality of life. However, additional therapies are still required because of undesirable drug-drug interactions; drug-food interactions; non-adherence to therapy; and drug resistance due to mutation of the enzyme target.

Currently, almost all HIV positive patients are treated with therapeutic regimens of antiretroviral drug combinations termed, highly active antiretroviral therapy (“HAART”). However, HAART therapies are often complex because a combination of different drugs must be administered often daily to the patient to avoid the rapid emergence of drug-resistant HIV-1 variants. Despite the positive impact of HAART on patient survival, drug resistance can still occur. The emergence of multidrug-resistant HIV-1 isolates has serious clinical consequences and must be suppressed with a new drug regimen, known as salvage therapy.

Current guidelines recommend that salvage therapy includes at least two, and preferably three, fully active drugs. Typically, first-line therapies combine three to four drugs targeting the viral enzymes reverse transcriptase and protease. One option for salvage therapy is to administer different combinations of drugs from the same mechanistic class that remain active against the resistant isolates. However, the options for this approach are often limited, as resistant mutations frequently confer broad cross-resistance to different drugs in the same class. Alternative therapeutic strategies have recently become available with the development of fusion, entry, and integrase inhibitors. However, resistance to all three new drug classes has already been reported both in the lab and in patients. Sustained successful treatment of HIV-1-infected patients with antiretroviral drugs will therefore require the continued development of new and improved drugs with new targets and mechanisms of action.

For example, over the last decade HIV inhibitors have been reported to target the protein-protein interaction between HIV-1 integrase and Lens Epithelium Derived Growth Factor/p75 (“LEDGF”). LEDGF is a cellular transcriptional cofactor of HIV-1 integrase that promotes viral integration of reverse transcribed viral cDNA into the host cell's genome by tethering the preintegration complex to the chromatin. Because of its crucial role in the early steps of HIV replication, the interaction between LEDGF and integrase represents another attractive target for HIV drug therapy.

U.S. provisional patent application 62/027,359 discloses certain isoindoline compounds having the following formula:

SUMMARY OF THE INVENTION

Briefly, in one aspect, the present invention discloses compounds of Formula I:

X is O or CH2;

R2is H, C1-6alkyl, C5-14aryl, C3-7cycloalkyl, C3-7cycloalkenyl, C3-9heterocycle, or C5-9heteroaryl, wherein each R2group is optionally substituted by one to four substituents selected from halo, C1-6alkyl, C1-6hetereoalkyl, or C1-6alkylene or C1-6hetereoalklylene wherein said C1-6alkylene or C1-6hetereoalklylene is bonded to adjacent carbon atoms on said C5-14aryl, C3-7cycloalkyl, C3-7cycloalkenyl, C3-9heterocycle, or C5-9heteroaryl to form a fused ring;

each R5is independently H, C1-3alkyl, C3-6cycloalkyl, CH2F, CHF2, or CF3, with the proviso that at least one R5is other than CH3;

each R6is independently H, or C1-3alkyl, C5-14aryl, C3-9heterocycle, C5-9heteroaryl, —C(O)NR4, or —C(O)NHR4, or both R6may together comprise 2-4 carbon atoms and join together to form a bridged ring system.

and wherein each heterocycle, heteroaryl, heteroalkyl, and heteroalkylene comprises one to three heteroatoms selected from S, N, B, or O.

In another aspect the present invention discloses pharmaceutically acceptable salts of the compounds of Formula I.

In another aspect, the present invention discloses pharmaceutical compositions comprising a compound of Formula I or a pharmaceutically acceptable salt thereof.

In another aspect, the present invention discloses a method for treating a viral infection in a patient mediated at least in part by a virus in the retrovirus family of viruses, comprising administering to said patient a composition comprising a compound of Formula I, or a pharmaceutically acceptable salt thereof. In some embodiments, the viral infection is mediated by the HIV virus.

In another aspect, a particular embodiment of the present invention provides a method of treating a subject infected with HIV comprising administering to the subject a therapeutically effective amount of a compound of Formula I, or a pharmaceutically acceptable salt thereof.

In yet another aspect, a particular embodiment of the present invention provides a method of inhibiting progression of HIV infection in a subject at risk for infection with HIV comprising administering to the subject a therapeutically effective amount of a compound of Formula I, or a pharmaceutically acceptable salt thereof. Those and other embodiments are further described in the text that follows.

In accordance with another embodiment of the present invention, there is provided a method for preventing or treating a viral infection in a mammal mediated at least in part by a virus in the retrovirus family of viruses which method comprises administering to a mammal, that has been diagnosed with said viral infection or is at risk of developing said viral infection, a compound as defined in Formula I, wherein said virus is an HIV virus and further comprising administration of a therapeutically effective amount of one or more agents active against an HIV virus, wherein said agent active against the HIV virus is selected from the group consisting of Nucleotide reverse transcriptase inhibitors; Non-nucleotide reverse transcriptase inhibitors; Protease inhibitors; Entry, attachment and fusion inhibitors; Integrase inhibitors; Maturation inhibitors; CXCR4 inhibitors; and CCR5 inhibitors.

DETAILED DESCRIPTION OF THE INVENTION

Preferably X is O.

Preferably W is a bond.

Preferably R2is optionally substituted phenyl. Most preferably, R2is phenyl substituted by one to four substituents selected from fluorine, methyl, —CH2CH2CH2O— wherein said —CH2CH2CH2O— is bonded to adjacent carbon atoms on said phenyl to form a bicyclic ring, or —NHCH2CH2O— wherein said —NHCH2CH2O— is bonded to adjacent carbon atoms on said phenyl to form a bicyclic ring.

Preferably the stereochemistry on the carbon to which OR1is bound is as depicted below.

“Pharmaceutically acceptable salt” refers to pharmaceutically acceptable salts derived from a variety of organic and inorganic counter ions well known in the art and include, by way of example only, sodium, potassium, calcium, magnesium, ammonium, and tetraalkylammonium, and when the molecule contains a basic functionality, salts of organic or inorganic acids, such as hydrochloride, hydrobromide, tartrate, mesylate, acetate, maleate, and oxalate. Suitable salts include those described in P. Heinrich Stahl, Camille G. Wermuth (Eds.), Handbook of Pharmaceutical Salts Properties, Selection, and Use; 2002.

EXAMPLES

The compounds of this invention may be made by a variety of methods, including well-known standard synthetic methods. Illustrative general synthetic methods are set out below and then specific compounds of the invention are prepared in the working examples.

The following examples serve to more fully describe the manner of making and using the above-described invention. It is understood that these examples in no way serve to limit the true scope of the invention, but rather are presented for illustrative purposes. In the examples below and the synthetic schemes above, the following abbreviations have the following meanings. If an abbreviation is not defined, it has its generally accepted meaning.

dd=doublet of doublets

h or hr=hours

HCV=hepatitis C virus

HPLC=high performance liquid chromatography

J=coupling constant (given in Hz unless otherwise indicated)

M+H+=parent mass spectrum peak plus H+

ppm=parts per million

To an ice cold solution of 3-fluorobenzamide (100 mg, 0.72 mmol) in DMF (2 mL) was added NaH (72 mg, 1.80 mmol). After 10 min, a solution of 3-cyclopropylprop-2-yn-1-yl methanesulfonate (251 mg, 1.44 mmol) (made according to WO20095674/A2) was added and the reaction mixture warmed to ambient temperature. After 1 h, the reaction mixture was quenched with sat. NH4Cl aq. and extracted with EtOAc. The organic layer was washed with brine, dried over Na2SO4, filtered, and concentrated in vacuo. The residue was purified by silica gel chromatography (0-30% EtOAc in PE) to afford the title compound (44 mg, 21% yield) as a white solid. LC/MS (m/z) ES+=296.1 (M+1).

The title compound was prepared from the known procedure as described in WO2010/130034.

The title compound was prepared from the known procedure as described in WO2010/130842

A suspension of (S)-((2-(tert-Butoxy)-4-(8-fluoro-5-methylchroman-6-yl)but-3-yn-1-yl)oxy)(tert-butyl)diphenylsilane (108 mg, 0.353 mmol) in DCM (5 mL) was treated with Dess Martin periodinane (300 mg, 0.706 mmol). After 18 h, the reaction mixture was quenched with sat. aq. Na2S2O3and the layers partitioned. The organic layer was washed with brine, dried (Na2SO4), filtered and concentrated in vacuo to afford the title compound as a yellow oil (312 mg) that was used immediately without further purification. LCMS (m/z ES+): 343 (M+23).

A mixture of R-BINAP (68 mg, 0.11 mmol) and [Rh(cod)2]BF4(45 mg, 0.11 mmol) in DCM (2 mL) was stirred under H2atmosphere for 1 hr to generate the activated catalyst. The resulting mixture was purged with N2and heated up to 40 ° C. before the addition of methyl (S)-2-(tert-butoxy)-4-(8-fluoro-5-methylchroman-6-yl)but-3-ynoate (120 mg, 0.36 mmol) in DCM (2 mL). A solution of N,N-bis(3-cyclopropylprop-2-yn-1-yl)-3-fluorobenzamide (318 mg, 1.08 mmol) in DCM (6 mL) was added dropwise to the reaction mixture over 30 min and the mixture was stirred at 40° C. for another 30min. The resulting mixture was concentrated under reduced pressure and purified by silica gel chromatography (0-30% EtOAc in PE) to afford the title compound as a yellow oil (40 mg, 18% yield). LCMS (m/z) ES+=630.2 (M+1).

An ice cold solution of benzyl di(prop-2-yn-1-yl)carbamate (535 mg, 2.354 mmol) in acetone (12 mL) was shielded from light and treated with NBS (838 mg, 4.71 mmol) and silver nitrate (160 mg, 0.942 mmol). After 100 min, the reaction mixture was diluted with EtOAc and washed with sat. aq. Na2S2O3and sat. aq. NaHCO3. The layers were partitioned and the organic layer washed with brine, dried (Na2SO4), filtered and concentrated in vacuo to afford the title compound as a yellow oil that was used without further purification. LCMS (m/z) ES+=381.8 (M−1).

A two-necked round bottom flask was charged with [Rh(cod)2]BF4(0.084 g, 0.206 mmol) and (+/−)-BINAP (0.128 g, 0.206 mmol) in anhydrous DCM (4 mL) was sparged with H2for 5 minutes and stirred under 1 atm (balloon) of H2. After 1 hour the reaction mixture was sparged with N2and treated with a solution of (S)-methyl 2-hydroxy-4-(p-tolyl)but-3-ynoate (210 mg, 1.028 mmol) in dichloromethane (1 mL) and placed in a preheated 50° C. oil bath. The reaction mixture was then treated dropwise with a solution of benzyl bis(3-bromoprop-2-yn-1-yl)carbamate (594 mg, 1.542 mmol) in dichloromethane (3 mL) over 85 min. After 30 min, the reaction mixture was cooled to ambient temperature and concentrated in vacuo and purified by silica gel chromatography (0-60% EtOAc-hexanes) to afford the title compound (0.52 g, 85%) as a yellow oil. LCMS (m/z) ES+=610 (M+23).

A solution of (S)-benzyl 5-(1-(tert-butoxy)-2-methoxy-2-oxoethyl)-6-(p-tolyl)-4,7-bis(trifluoromethyl)isoindoline-2-carboxylate (56 mg, 0.090 mmol) in ethanol (2 mL) was purged and filled with N2, treated with Pd/C (10 wt %, degussa) (9.56 mg, 8.98 pmol), and then bubbled with H2for 3 min and placed under a balloon of H2(1 atm). After 50 min, the reaction mixture was filtered through a pad of celite, washed with MeOH, EtOH and DCM, and then concentrated in vacuo to afford the title compound (54 mg) that was used without further purification. LCMS (m/z) ES+=490.4 (M+H).

A solution of (S)-methyl 2-(tert-butoxy)-2-(2-(3-fluorobenzoyl)-6-(p-tolyl)-4,7-bis(trifluoromethyl)isoindolin-5-yl)acetate (60.8 mg, 0.099 mmol, 97% yield) in 1,4-Dioxane (2.5 mL) was treated with LiOH (0.511 mL, 1.022 mmol, 2.0 M) and stirred at 70° C. After 18 h, the mixture was cooled ambient temperature and concentrated in vacuo. The residue was purified by reverse phase HPLC (15-95% MeCN/H2O-0.1% TFA) to afford a mixture of products that was redissolved in 1,4-dioxane (0.75 mL) and ethanol (0.75 mL), treated with 2 M LiOH (0.612 mL, 1.224 mmol), and stirred at 85 ° C. After 72 h, the reaction was cooled to ambient temperature and concentrated in vacuo to afford (S)-2-(tert-butoxy)-2-(6-(p-tolyl)-4,7-bis(trifluoromethyl)isoindolin-5-yl)acetic acid, LCMS (m/z) ES+=476.42 (M+1).

A solution (2S)(M)-benzyl 5+1-(tert-butoxy)-2-methoxy-2-oxoethyl)-6-(8-fluoro-5-methylchroman-6-yl)-4,7-bis(trifluoromethyl)isoindoline-2-carboxylate (105 mg, 0.151 mmol) in methanol (2 mL) was purged and filled with N2, treated with Pd/C (10 wt %, degussa) (16.0 mg, 0.015 mmol), and then bubbled with H2for 3 min. The reaction was stirred at ambient temperature and under an atmosphere of H2. After 1.5 h, the mixture was diluted with ethanol (1 mL), Pd/C (10 wt %, degussa) (16.02 mg, 0.015 mmol), bubbled with H2for 2 min, and then stirred at ambient temperature and under an atmosphere of H2. After 2.5 h, the mixture was flushed with N2and filtered through a pad of celite, washed with MeOH, EtOAc and DCM, and then concentrated in vacuo to give crude the title compound (73.6 mg, 0.131 mmol, 87% yield) as dark yellow oil. The crude product was used as is. LCMS (m/z) ES+=564.43 (M+1).

Antiviral HIV activity and cytotoxicity values for compounds of the invention from Table 1 were measured in parallel in the HTLV-1 transformed cell line MT-4 based on the method previously described (Hazen et al., 2007, In vitro antiviral activity of the novel, tyrosyl-based human immunodeficiency virus (HIV) type 1 protease inhibitor brecanavir (GW640385) in combination with other antiretrovirals and against a panel of protease inhibitor-resistant HIV (Hazen et al., “In vitro antiviral activity of the novel, tyrosyl-based human immunodeficiency virus (HIV) type 1 protease inhibitor brecanavir (GW640385) in combination with other antiretrovirals and against a panel of protease inhibitor-resistant HIV”,Antimicrob. Agents Chemother.2007, 51: 3147-3154; and Pauwels et al., “Sensitive and rapid assay on MT-4 cells for the detection of antiviral compounds against the AIDS virus”,J. of Virological Methods1987, 16: 171-185).

Luciferase activity was measured 96 hours later by adding a cell titer glo (Promega, Madison, Wis.). Percent inhibition of cell protection data was plotted relative to no compound control. Under the same condition, cytotoxicity of the compounds was determined using cell titer Glo™ (Promega, Madison, Wis.). IC50s were determined from a 10 point dose response curve using 3-4-fold serial dilution for each compound, which spans a concentration range >1000 fold.

These values are plotted against the molar compound concentrations using the standard four parameter logistic equation:

When tested in the MT4 assay compounds were found to have IC50values listed in Table 1.