Pyridinylaminopyrimidine derivatives, preparation process and use thereof

Abstract

The present invention relates to pyridinylaminopyrimidine derivatives represented by the following formula (I), and pharmaceutically acceptable salts, preparation process and use thereof, wherein R₁, R₂, R₃, R₄, R₅, m and A are defined as in the description. Pyridinylaminopyrimidine derivatives of the present invention can selectively inhibit the activity of mutant-type epidermal growth factor receptor (EGFR), have a good inhibition for the cancer cell proliferation, and therefore can be used as a therapeutic agent for treating tumors and relevant diseases.

##STR00001##

Description

RELATED APPLICATIONS

This application is a 35 U.S.C. § 371 national phase application of and claims priority to PCT Application PCT/CN2015/000540 filed Jul. 29, 2015, which claims priority to Chinese Application No. 201410365911.4 filed Jul. 29, 2014, the entire contents of which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to pyridinylaminopyrimidine derivatives, which selectively inhibit the activity of mutation-type epidermal growth factor receptor (EGFR), a pharmaceutically acceptable salt thereof, a process for preparing the same, a pharmaceutical composition containing said derivative and a pharmaceutically acceptable salt thereof, uses of said derivative and a pharmaceutically acceptable salt thereof in treating some mutation-type EGFR mediated diseases and in manufacture of a medicament for treating some mutation-type EGFR mediated diseases.

BACKGROUND

Cancer has been considered as a disease of the intracellular signal transconducing system or signal transduction mechanism. The most common cause of cancer is a series of defects, either in proteins, when they are mutated, or in the regulation of the quantities of the proteins in the cells such that they are over or under produced. Mutations to the cell surface receptors, which usually transduce the signals into the cells by means of tyrosine kinases, can lead to activation of the kinase in the absence of ligand, and passing of a signal which does not really exist. Alternatively, many receptor tyrosine kinases can be overexpressed on the cell surface leading to an inappropriately strong response to a weak signal.

Epidermal cell growth factors receptors (EGFR) are identified as one significant driving factor in the process for cellular growth and proliferation. The epidermal cell growth factors receptors family is composed of EGFR (Erb-B1), Erb-B2 (HER-2/neu), Erb-B3 and Erb-B4. The epidermal cell growth factors receptors are concerned in the process for most cancers, such as lung cancer, colon cancer and breast cancer. The overexpression and mutation of EGFR have been proved to be the leading risk factor for a breast cancer with poor prognosis. Besides, it has been verified that each of the above four members of the receptors family can aggregate with another member into a heterodimer, and form a signal transduction complex. Overexpression of one or more member(s) of this family in a malignant tumor will result in a synergistic signal transduction.

EGFR belongs to the protein tyrosine kinase (PTK) family. The protein tyrosine kinase is an group of enzymes which catalyze the transportation of phosphate groups from adenosine triphosphate (ATP) to the tyrosine residue located in a protein substrate. Protein tyrosine kinases function in normal cell growth. The overexpression and mutation of EGFR may cause the activation of receptors without ligands and the phosphorylation of some proteins, and then the signal for cell division is produced. As a result, EGFR may magnify the weak signal excessively by its own tyrosine-kinase action, and render the overproliferation of cells.

Specific PTK inhibitors as a potential anti-cancer therapeutic drug are of wide concern. Typical representatives of currently market available EGFR reversible inhibitors include Gefitinib, Erlotinib and Lapatinib, and inhibit the EGFR wild-type and activating mutations (e.g. Exon 19 deletion activating mutation, or L858R activating mutation). Their structures are as follows, and are respectively useful for treating non-small cell lung cancer (NSCLC) and breast cancer. Clinical study proves gefitinib and erlotinib have a favorable therapeutic effect on NSCLC patients with EGFR exon 19 deletion or L858R mutation. However, their limitations are that patients develop drug resistance after treatment, so that inhibitors of this type are limited in their further clinical applications. The study shows that 50% of resistance formed after the treatment with gefitinib and erlotinib is associated with a second mutation occurred in EGFR (T790M) (Pao W. et al., Plos Med., 2:1-11, 2005). The therapeutic effect as reversible inhibitor is lost.

##STR00002##

T790M is located at the entrance of the ATP binding pocket of EGFR, and the size of its side chain directly affects the ability of EGFR binding to ATP. The T790M mutation spatially inhibits the interaction of the EGFR inhibitor and the ATP binding site, increases the affinity of EGFR to ATP, and makes the cells resistant to the EGFR inhibitors.

Compared to reversible EGFR inhibitors, irreversible EGFR inhibitors have very prominent advantages. Irreversible EGFR inhibitors can inhibit EGFR for a long time and are only limited by the normal rate of receptor re-binding (also called reversion). It is found that the irreversible EGFR inhibitor can covalently bind to the cysteine residue (Cys797) of the EGFR by Michael addition reaction and expand the binding sites of irreversible EGFR inhibitors and the ATP, so that the resistance caused by the T790M mutation can be overcame to some extent (Li D et al., Oncogene, 27:4702-4711, 2008). Currently market available irreversible EGFR inhibitors include BIBW-2992 (Afatinib), those in development include HKI-272 (Neratinib), EKB-569 (Pelitinib), PF00299804 (Dacomitinib) and the like, and their structures are as follows.

##STR00003##

However, these irreversible EGFR inhibitors, which can inhibit EGFR T790M, also have a large inhibition effect on the wild-type EGFR, leading to severe side effects such as diarrhea, erythra, nausea, anorexia, and weakness (Besse, B. et al. Eur. J. Cancer Suppl., 6, 64, abstr. 203, 2008; Janne, P. A. et al., J. Clin. Oncol., 25: 3936-3944, 2007). Accordingly although it is reported in the literature that in the preclinical study, BIBW2992 (Afatinib) and PF00299804 (Dacomitinib) show a significant antitumor activity and can inhibit the activities of EGFR and EGFR T790M, however, due to the occurrence of these adverse reactions, the clinical dose and the effective blood drug concentration are limited in the clinical course. Therefore, there is no remarkable progress for BIBW2992 (Afatinib) and PF00299804 (Dacomitinib) in overcoming the T790M resistant mutation (Katakami N, Atagi S, Goto K, et al. [J]. Journal of Clinical Oncology, 2013, 31(27): 3335-3341.; Jänne P A, Boss D S, Camidge D R, et al. [J]. Clinical Cancer Research, 2011, 17(5): 1131-1139.; Landi L, Cappuzzo F. [J]. Translational Lung Cancer Research, 2013, 2(1): 40-49.).

The above-mentioned reversible or irreversible EGFR inhibitors, being currently marketed or under development, are mainly quinazoline compounds. The currently reported quinazoline EGFR inhibitors are the ATP competitive inhibitors of wild-type EGFR, leading to the occurrence of some side-reaction. In 2009, a group of pyrimidine-based irreversible EGFR inhibitors which are specific to the EGFR T790M was reported by the researchers, and the structures are shown below. Compared to the existing aniline quinazoline EGFR inhibitors, these pyrimidine-based compounds have a 30-100 fold higher inhibition activity for the EGFR T790M, and a 100 fold lower inhibition activity for the wild-type EGFR (WenjunZhou et al., Nature, 462:1070-1074, 2009). However, these pyrimidine-based compounds did not enter the clinical study later.

##STR00004##

International Patent Application WO 2012/061299 A1 filed by Avila Therapeutics discloses another series of pyrimidine-based compounds, and the structures are shown below. The representative compound is CO1686. It is reported in the literature that CO1686 can selectively act on the EGFR activating mutation and the T790M resistant mutation, but have a weak inhibition effect on the wild-type EGFR (Walter A O, Sjin R T T, Haringsma H J, et al. [J]. Cancer discovery, 2013, 3(12): 1404-1415.). Currently, this compound is ready to enter Phase-II clinical stage.

##STR00005##

International Patent Application WO 2013/014448 A1 filed by ASTRAZENECA AB also discloses a series of pyrimidine-based compounds, and their structures are shown below. The representative compound is AZD9291. This compound has a better inhibition effect on the EGFR activating mutation and the T790M resistant mutation than the wild-type EGFR, and is now in Phase I clinical stage.

##STR00006##

There is an urgent demand in the current anti-tumor field to overcome the problems of the clinically common EGFR resistant mutation (e.g. T790M mutation) and the toxic and side effects of the existing EGFR inhibitors, i.e., develop more small molecule inhibitors that show a higher inhibition effect on some activating mutation and resistant mutation EGFRs and a lower inhibition effect on the wild-type EGFR. During the study of the EGFR inhibitors, the present inventors surprisingly discovered a group of pyridinylaminopyrimidine derivatives, which have a remarkably higher inhibition activity on the EGFR activating mutation (e.g. Exon 19 deletion activating mutation, or L858R activating mutation) and the T790M resistant mutation than the wild-type EGFR (WT EGFR), and has good selectivity, low toxic and side effects, and good safety. It is expected that this kind of inhibitors will have a good therapeutic effect, can overcome the problems of drug resistance and toxic/side effects, and accordingly may have good development prospects.

SUMMARY OF THE INVENTION

The present invention provides a compound represented by the following general formula (I), or a pharmaceutically acceptable salt thereof:

##STR00007##
wherein,
Ring A is aryl or heteroaryl;
R₁ is selected from a group consisting of hydrogen, halogen, C₁-C₄alkyl, haloC₁-C₄alkyl, C₂-C₆alkenyl, C₂-C₆alkynyl or —CN;
R₂ is selected from a group consisting of C₁-C₄alkyl, haloC₁-C₄alkyl, C₂-C₆alkenyl, —(CH₂)_qOR₇, —(CH₂)_qNR₇R₇′ or —(CH₂)_qC(O)R₇;
R₄ is

##STR00008##
Each R₅ is

Blank control OD: the OD value of the well of normally growed cells without the action of a drug.

Inhibitor OD: the OD value of the well of cells with the action of the added compounds to be screened.

The median inhibitory concentration (IC₅₀) value is obtained by the software GraphPad Prism 5.0 by the 4-parameter logistic curve fit calculation. Each experiment is repeated three times, and the average IC₅₀ value for three experiments is used as the final index for the inhibitory ability.

The pharmacodynamic action of the compound of the present invention in terms of inhibiting the growth of transplanted tumors in animal may be assayed by conventional methods. One preferable evaluation method of which is the inhibitory effect on the growth of subcutaneously transplanted tumors of human lung cancer H1975-bearing nude mice. The experimental method is as follows: human lung cancer H1975 cell strain (5×10⁶/each mouse) is inoculated to nude mice subcutaneously at the right side of the back thereof. After the tumors grow to 100-150 mm³ on average, the animals are divided into groups randomly according to the tumor size and the animal weight. The test compounds are administered by intragastric administration in a certain dosages, and solvent control groups are administered with equal amount of solvent by intragastric administration, wherein the administration is performed once per day for a continuous period of 12 days. During the entire experimental process, the animal weight and the tumor size are measured twice per week, so as to observe whether or not the toxic reaction occurs. The tumor volume is calculated as follows:
Tumor volume (mm³)=0.5×(Tumor major diameter×Tumor minor diameter²)

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is the tumor volume curve for subcutaneously transplanted tumors of human lung cancer H1975-bearing nude mice at the administration dosage of 25 mg/kg of the compound of Example 3 and AZD9291.

FIG. 2 is the body weight curve for human lung cancer H1975-bearing nude mice at the administration dosage of 25 mg/kg of the compound of Example 3 and AZD9291.

The present invention will be further illustrated hereinafter in connection with specific Examples. It should be understood that these Examples are only used to illustrate the present invention by the way of examples without limiting the scope thereof. In the following Examples, the experimental methods without specifying conditions are generally performed according to conventional conditions or based on the conditions recommended by the manufacturer. The parts and percentages are the parts and percentages by weight respectively, unless otherwise specified.

DETAILED DESCRIPTION OF THE INVENTION

I. Preparation Examples of the Compounds of the Present Invention

Intermediate 1a: N²-methyl-N²-[2-(dimethylamino)ethyl]-6-methoxy-3-nitropyridin-2,5-diamine hydrochloride

##STR00016##

Step 1: Synthesis of 6-chloro-2-methoxy-3-nitropyridine

##STR00017##

To a 250 mL three-necked flask were added 2,6-dichloro-3-nitropyridine (11.58 g, 60 mmol), 150 ml tetrahydrofuran and methanol (1.92 g, 60 mmol). The mixture was cooled to 0° C. To the mixture was added in batch 60% sodium hydride (2.4 g, 60 mmol). The resulting mixture was stirred at 0° C. for 1 hour, warmed up slowly to room temperature, and continued to stir for 1 hour. To the reaction mixture was added 100 ml ethyl acetate. The reaction mixture was washed successively with water (50 ml×2) and saturated brine (50 ml). The organic phase was dried with anhydrous sodium sulfate, filtered, evaporated under a reduced pressure to remove the solvent, purified by silica gel column chromatography (petroleum ether:ethyl acetate=30:1) to produce 7.3 g of a product with a yield of 64%.

¹H NMR (400 MHz, CDCl₃) δ 8.29 (d, J=8.3 Hz, 1H), 7.07 (d, J=8.3 Hz, 1H), 4.15 (s, 3H).

Step 2: Synthesis of 6-chloro-2-methoxypyridin-3-amine

##STR00018##

To a 100 mL single-necked flask were added 6-chloro-2-methoxy-3-nitropyridine (2.0 g, 10.6 mmol), ammonia chloride (2.8 g, 53.0 mmol) and 80 ml of a mixed solvent of ethanol and water (volume ratio=3:1). To the mixture was added in batch a reduced iron powders (3.0 g, 53.0 mmol). The mixture was stirred at 80° C. for 1.5 hours. The reaction mixture was cooled to room temperature, and filtered through diatomite. 150 ml ethyl acetate and 120 ml saturated sodium chloride were added to the filtrate. An organic layer was separated and dried with anhydrous sodium sulfate, and filtered. The filtrate was evaporated to dryness under a reduced pressure to produce a brown solid (1.6 g) with a yield of 95%. MS m/z: 159 [M+1].

Step 3: Synthesis of N-(6-chloro-2-methoxypyridin-3-yl)acetamide

##STR00019##

To a 250 mL single-necked flask were added 6-chloro-2-methoxypyridin-3-amine (1.6 g, 10.1 mmol), diisopropylethylamine (2.6 ml, 15.1 mmol) and 100 ml dichloromethane. The mixture was cooled to 5° C. in an ice bath. Acetyl chloride (0.86 ml, 12.1 mmol) was added. The reaction continued for 1.25 hours. The reaction mixture was washed successively with 80 ml water, 80 ml 1N hydrochloric acid and 80 ml saturated sodium chloride solution, dried with anhydrous sodium sulfate, filtered, and evaporated to dryness under a reduced pressure to produce 1.9 g of a brown solid with a yield of 94%. MS m/z: 201 [M+1].

Step 4: Synthesis of N-(6-chloro-2-methoxy-5-nitropyridin-3-yl)acetamide

##STR00020##

To a 100 mL single-necked flask were added N-(6-chloro-2-methoxypyridin-3-yl)acetamide (1.9 g, 9.47 mmol) and 20 ml trifluoroacetic anhydride. The mixture was cooled in an ice-salt bath to −10° C. Fuming nitric acid (0.4 ml, 9.47 mmol) was dropwisely added while the temperature was controlled to below −5° C. After the completion of dropwise addition, the reaction continued in an ice-salt bath for 1.25 hours. The reaction mixture was slowly added to crushed ice. A solid precipitated and was filtered. The resulting crude product was dried at 60° C., and added to ethyl acetate to form a slurry. 1.5 g of an beige solid was obtained with a yield of 65%. MS m/z: 244 [M−1].

¹H NMR (400 MHz, DMSO-d6) δ 9.90 (s, 1H), 9.17 (s, 1H), 4.06 (s, 3H), 2.17 (s, 3H).

Step 5: Synthesis of N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-methoxy-5-nitropyridin-3-yl}acetamide hydrochloride

##STR00021##

To a 100 mL single-necked flask were added N-(6-chloro-2-methoxy-5-nitropyridin-3-yl)acetamide 1.0 g, 4.1 mmol), 30 ml acetonitrile and N,N,N′-trimethylethylenediamine (0.6 g, 6.1 mmol). The mixture was reacted at 80° C. for 3 hours. The reaction mixture was concentrated under a reduced pressure to about ⅓ of the original volume. 50 ml ethyl acetate was added. The mixture was stirred for several minutes, a solid precipitated and was filtered to produce 1.1 g of an beige solid with a yield of 87%.

¹H NMR (400 MHz, DMSO-d6) δ 11.13 (s, 1H), 9.53 (s, 1H), 8.73 (s, 1H), 4.05 (s, 5H), 3.41 3.36 (m, 2H), 2.83 (s, 3H), 2.80 (s, 6H), 2.07 (s, 3H).

Step 6: Synthesis of N²-methyl-N²-[2-(dimethylamino)ethyl]-6-methoxy-3-nitropyridin-2,5-diamine hydrochloride

##STR00022##

To a 50 mL single-necked flask were added N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-methoxy-5-nitropyridin-3-yl}acetamide (600 mg, 1.93 mmol), 15 ml methanol and 0.3 ml concentrated hydrochloric acid. The mixture was reacted at 60° C. overnight. The reaction mixture was evaporated to dryness under a reduced pressure. 100 ml dichloromethane and 80 ml saturated sodium bicarbonate were added. The resulting mixture was stirred until no bubble produced. An organic layer was separated and dried with anhydrous sodium sulfate, filtered, and concentrated under a reduced pressure. The residue was purified by silica gel column chromatography (dichloromethane:methanol=10:1) to produce 400 mg of a brown solid. MS m/z: 270 [M+1].

¹H NMR (400 MHz, DMSO-d6) δ 11.20 (s, 1H), 8.16 (s, 1H), 4.06-4.02 (m, 5H), 3.38 (br s, 2H), 2.83 (s, 3H), 2.80 (s, 3H), 2.79 (s, 3H).

Intermediate 1b: Synthesis of N²-methyl-N²-[2-(dimethylamino)ethyl]-6-isopropyloxy-3-nitropyridin-2,5-diamine

##STR00023##

Step 1: Synthesis of 6-chloro-2-isopropyloxy-3-nitropyridine

##STR00024##

The compound was synthesized in the same manner as those in Step 1 of Intermediate 1a.

¹H NMR (400 MHz, CDCl₃) δ 8.22 (d, J=8.3 Hz, 1H), 6.98 (d, J=8.3 Hz, 1H), 5.50 (hept, J=6.2 Hz, 1H), 1.43 (d, J=6.2 Hz, 6H).

Step 2: Synthesis of 6-chloro-2-isopropyloxypyridin-3-amine

##STR00025##

The compound was synthesized in the same manner as those in Step 2 of Intermediate 1a with a yield of 74%. MS m/z: 187 [M+1], 189.

Step 3: Synthesis of N-(6-chloro-2-isopropyloxypyridin-3-yl)acetamide

##STR00026##

The compound was synthesized in the same manner as those in Step 3 of Intermediate 1a with a yield of 83%. MS m/z: 229 [M+1], 231.

Step 4: Synthesis of N-(6-chloro-2-isopropyloxy-5-nitropyridin-3-yl)acetamide

##STR00027##

The compound was synthesized in the same manner as those in Step 4 of Intermediate 1a with a yield of 33%. MS m/z: 272 [M−1].

Step 5: Synthesis of N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxy-5-nitropyridin-3-yl}acetamide

##STR00028##

To a 500 mL single-necked flask were added N-(6-chloro-2-isopropyloxy-5-nitropyridin-3-yl)acetamide (15 g, 54.8 mmol), 150 ml acetonitrile, N,N,N′-trimethylethylenediamine (7.28 g, 71.3 mmol) and potassium carbonate (15.15 g, 110 mmol). The mixture was reacted at 80° C. overnight. The reaction mixture was cooled to room temperature, and filtered. The filtrate was evaporated to dryness under a reduced pressure to produce 18.6 g of a product with a yield of 100%.

MS m/z: 340 [M+1].

Step 6: Synthesis of N²-methyl-N²-[2-(dimethylamino)ethyl]-6-isopropyloxy-3-nitropyridin-2,5-diamine

##STR00029##

The compound was synthesized in the same manner as those in Step 6 of Intermediate 1a with a yield of 38%. MS m/z: 298 [M+1].

Intermediate 1c: N²-methyl-N²-[2-(dimethylamino)ethyl]-6-(2,2,2-trifluoroethoxyl)-3-nitropyridin-2,5-diamine

##STR00030##

Step 1: Synthesis of 6-chloro-2-(2,2,2-trifluoroethoxyl)-3-nitropyridine

##STR00031##

The compound was synthesized in the same manner as those in Step 1 of Intermediate 1a with a yield of 80%.

Step 2: Synthesis of 6-chloro-2-(2,2,2-trifluoroethoxyl)pyridin-3-amine

##STR00032##

The compound was synthesized in the same manner as those in Step 2 of Intermediate 1a with a yield of 83%.

Step 3: Synthesis of N-[6-chloro-2-(2,2,2-trifluoroethoxyl)pyridin-3-yl]acetamide

##STR00033##

The compound was synthesized in the same manner as those in Step 3 of Intermediate 1a with a yield of 71%. MS m/z: 269 [M+1], 271.

Step 4: Synthesis of N-[6-chloro-2-(2,2,2-trifluoroethoxyl)-5-nitropyridin-3-yl]acetamide

##STR00034##

The compound was synthesized in the same manner as those in Step 4 of Intermediate 1a with a yield of 53%. MS m/z: 314 [M+1], 316.

¹H NMR (400 MHz, CDCl₃) δ 9.37 (s, 1H), 7.63 (s, 1H), 4.93 (q, J=8.2 Hz, 2H), 2.30 (s, 3H).

Step 5: Synthesis of N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-(2,2,2-trifluoroethoxyl)-5-nitropyridin-3-yl}acetamide

##STR00035##

To a 25 mL single-necked flask were added N-[6-chloro-2-(2,2,2-trifluoroethoxyl)]-5-nitropyridin-3-yl)acetamide (626 mg, 2 mmol), 10 ml acetonitrile, N,N,N′-trimethylethylenediamine (224 mg, 2.2 mmol) and potassium carbonate (138 mg, 4 mmol). The mixture was stirred at room temperature overnight. To the reaction mixture was added 100 ml ethyl acetate. The resulting mixture was washed with 20 ml water, dried with anhydrous sodium sulfate, and evaporated under a reduced pressure to remove the solvent to produce 710 mg of a product with a yield of 94%. MS m/z: 380 [M+1].

Step 6: Synthesis of N²-methyl-N²-[2-(dimethylamino)ethyl]-6-(2,2,2-trifluoroethoxyl)-3-nitropyridin-2,5-diamine

##STR00036##

The compound was synthesized in the same manner as those in Step 6 of Intermediate 1a with a yield of 100%. MS m/z: 338 [M+1].

Intermediate 1d: tert-butyl {5-acrylamide-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxypyridin-3-yl}carbamate

##STR00037##

Step 1: Synthesis of N-tert-butoxycarbonyl-N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxy-5-nitropyridin-3-yl}acetamide

##STR00038##

To a 500 mL single-necked flask were added N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxy-5-nitropyridin-3-yl}acetamide (18.6 g, 54.8 mmol), 4-dimethylaminopyridine (0.67 g, 5.48 mmol), 150 ml acetonitrile and di-tert-butyl dicarbonate (59.8 g, 274 mmol). The mixture was reacted at 80° C. for 2.5 hours. The reaction mixture was cooled to room temperature, was evaporated to dryness under a reduced pressure, and purified by silica gel column chromatography (dichloromethane methanol=10:1) to produce 24 g of a product with a yield of 100%.

Step 2: Synthesis of tert-butyl {6-({[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxy-5-nitropyridin-3-yl}carbamate

##STR00039##

To a 500 mL single-necked flask were added N-tert-butoxycarbonyl-N-{6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxy-5-nitropyridin-3-yl}acetamide (24 g, 54.6 mmol) and 240 ml methanol. The mixture was cooled to 0° C. Sodium methoxide (2.95 g, 54.6 mmol) was added. The mixture was slowly warmed up to room temperature and reacted overnight. The reaction mixture was concentrated under a reduced pressure. The residue was dissolved in 300 ml ethyl acetate, and washed with 100 ml water. The organic phase was dried with anhydrous sodium sulfate, filtered, and evaporated to dryness under a reduced pressure to produce 18 g of a product with a yield of 83%.

Step 3: Synthesis of tert-butyl {5-amino-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxypyridin-3-yl}carbamate

##STR00040##

The compound was synthesized in the same manner as those in Step 2 of Intermediate 1a with a yield of 97%.

MS m/z: 368 [M+1].

¹H NMR (400 MHz, DMSO-d6) δ 7.61 (s, 1H), 7.44 (s, 1H), 6.74 (br s, 2H), 5.09-4.96 (m, 1H), 3.29 (t, J=5.8 Hz, 2H), 3.19 (t, J=5.7 Hz, 2H), 2.70 (s, 6H), 2.56 (s, 3H), 1.45 (s, 9H), 1.26 (d, J=6.2 Hz, 6H).

Step 4: Synthesis of tert-butyl {5-acrylamide-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxypyridin-3-yl}carbamate

##STR00041##

To a 500 ml three-necked flask were added tert-butyl {5-amino-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-isopropyloxypyridin-3-yl}carbamate (9 g, 24.49 mmol), trimethylamine (6.83 ml, 49.0 mmol) and 250 ml dichloromethane. The reaction mixture was cooled in an ice-water bath to below 5° C. Acryloyl chloride (2.1 ml, 25.7 mmol) was dropwisely added. The resulting mixture was continued to react for 1 hour. The reaction mixture was washed successively with 150 ml saturated sodium bicarbonate solution and 150 ml saturated brine, dried with anhydrous sodium sulfate, and filtered. The filtrate was evaporated to dryness under a reduced pressure to produce 5 g of a product with a yield of 48%. MS m/z: 422 [M+1].

¹H NMR (400 MHz, DMSO-d6) δ 9.76 (s, 1H), 8.16 (s, 1H), 7.88 (s, 1H), 6.44 (dd, J=17.0, 10.1 Hz, 1H), 6.22 (dd, J=17.0, 1.9 Hz, 1H), 5.74 (dd, J=10.1, 1.9 Hz, 1H), 5.22-5.13 (m, 1H), 3.09 (t, J=6.5 Hz, 2H), 2.77 (s, 3H), 2.41 (t, J=6.5 Hz, 2H), 2.18 (s, 6H), 1.45 (s, 9H), 1.31 (d, J=6.2 Hz, 6H).

Intermediate 1e: tert-butyl {5-acrylamide-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-(2,2,2-trifluoroethoxyl)pyridin-3-yl}carbamate

##STR00042##

The compound was synthesized in the same manner as those in Step 1 of Intermediate 1d with a yield of 99%. MS m/z: 480 [M+1].

Step 2: Synthesis of tert-butyl {6-{[2-(dimethylamino)ethyl](methyl)amino}-2-(2,2,2-trifluoroethoxyl)-5-nitropyridin-3-yl}carbamate

##STR00043##

The compound was synthesized in the same manner as those in Step 2 of Intermediate 1d with a yield of 88%. MS m/z: 438 [M+1].

Step 3: Synthesis of tert-butyl {5-amino-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-(2,2,2-trifluoroethoxyl)pyridin-3-yl}carbamate

##STR00044##

The compound was synthesized in the same manner as those in Step 2 of Intermediate 1a with a yield of 76%. MS m/z: 408 [M+1].

Step 4: Synthesis of tert-butyl {5-acrylamide-6-{[2-(dimethylamino)ethyl](methyl)amino}-2-(2,2,2-trifluoroethoxyl)pyridin-3-yl}carbamate

##STR00045##

The compound was synthesized in the same manner as those in Step 4 of Intermediate 1d with a yield of 62%. MS m/z: 462 [M+1].

¹H NMR (400 MHz, CDCl₃) δ 10.11 (s, 1H), 9.35 (s, 1H), 6.61 (s, 1H), 6.46 (dd, J=16.9, 1.7 Hz, 1H), 6.39-6.25 (m, 1H), 5.70 (dd, J=10.0, 1.8 Hz, 1H), 4.76 (q, J=8.5 Hz, 2H), 2.96 (s, 2H), 2.71 (s, 3H), 2.42 (s, 2H), 2.34 (s, 6H), 1.53 (s, 9H).

Intermediate 2a: 3-(2-chloropyrimidin-4-yl)-1-methyl-1H-indole

##STR00046##

To a 500 mL single-necked flask were added 2,4-dichloropyrimidine (14.9 g, 100 mmol), 1-methyl-1H-indole (13 g, 100 mmol), 200 ml 1,2-dichloroethane and aluminium chloride (13.9 g, 120 mmol). The mixture was stirred at 80° C. for 1.5 hours. The reaction mixture was cooled to room temperature in an ice bath. 120 ml methanol and 400 ml water were added to quench the reaction. A solid precipitated and was filtered. The filter cake was washed with methanol, and dried in vacuum to produce 17.2 g of a product with a yield of 71%. MS m/z: 244 [M+1], 246.

¹H NMR (400 MHz, DMSO-d6) δ 8.53 (d, J=5.5 Hz, 1H), 8.49 (s, 1H), 8.42 (dd, J=7.0, 1.5 Hz, 1H), 7.81 (d, J=5.5 Hz, 1H), 7.56 (dd, J=7.0, 1.2 Hz, 1H), 7.33-7.26 (m, 2H), 3.90 (d, J=5.2 Hz, 3H).

Intermediate 2b: 3-(2,5-dichloropyrimidin-4-yl)-1-methyl-1H-indole

##STR00047##

The compound was synthesized in the same manner as those in Intermediate 2a with a yield of 87%. MS m/z: 278[M+1], 279, 280.

¹H NMR (400 MHz, DMSO-d6) δ 8.79 (s, 1H), 8.74 (s, 1H), 8.56 (dd, J=7.3, 1.2 Hz, 1H), 7.62 (d, J=7.6 Hz, 1H), 7.39-7.34 (m, 1H), 7.34-7.29 (m, 1H), 3.97 (s, 3H).

Intermediate 2c: 3-(2-chloropyrimidin-4-yl)-1-methyl-5-fluoro-1H-indole

##STR00048##

The compound was synthesized in the same manner as those in Intermediate 2a with a yield of 29%. MS m/z: 262 [M+1], 264.

¹H NMR (400 MHz, DMSO-d6) δ 8.55 (s, 1H), 8.53 (d, J=5.5 Hz, 1H), 8.10 (dd, J=10.3, 2.5 Hz, 1H), 7.80 (d, J=5.5 Hz, 1H), 7.60 (dd, J=8.9, 4.6 Hz, 1H), 7.17 (td, J=9.1, 2.6 Hz, 1H), 3.90 (s, 3H).

Intermediate 2d: 3-(2-chloropyrimidin-4-yl)-1-methyl-6-fluoro-1H-indole

##STR00049##

The compound was synthesized in the same manner as those in Intermediate 2a. MS m/z: 262 [M+1], 264.

¹H NMR (400 MHz, DMSO-d6) δ 8.54 (d, J=5.5 Hz, 1H), 8.49 (s, 1H), 8.39 (dd, J=8.8, 5.6 Hz, 1H), 7.81 (d, J=5.5 Hz, 1H), 7.47 (dd, J=9.9, 2.3 Hz, 1H), 7.14 (td, J=9.6, 2.4 Hz, 1H), 3.86 (s, 3H).

Intermediate 2e: 3-(2-chloropyrimidin-4-yl)-1-methyl-5,6-difluoro-1H-indole

##STR00050##

The compound was synthesized in the same manner as those in Intermediate 2a. MS m/z: 280 [M+1], 282.

¹H NMR (400 MHz, DMSO-d6) δ 8.54 (d, J=5.5 Hz, 1H), 8.52 (s, 1H), 8.22 (dd, J=11.7, 8.2 Hz, 1H), 7.79 (d, J=5.5 Hz, 1H), 7.73 (dd, J=11.2, 7.0 Hz, 1H), 3.86 (s, 3H).

Intermediate 2f: 3-(2,5-dichloropyrimidin-4-yl)-1-methyl-6-fluoro-1H-indole

##STR00051##

The compound was synthesized in the same manner as those in Intermediate 2a. MS m/z: 296 [M+1], 297, 298.

¹H NMR (400 MHz, CDCl₃) δ 8.69 (dd, J=8.9, 5.5 Hz, 1H), 8.50 (s, 1H), 8.41 (s, 1H), 7.17 7.07 (m, 2H), 3.90 (s, 3H).

Intermediate 2g: 3-(2,5-dichloropyrimidin-4-yl)-1-methyl-5,6-difluoro-1H-indole

##STR00052##

The compound was synthesized in the same manner as those in Intermediate 2a. MS m/z: 314 [M+1], 315, 316.

¹H NMR (400 MHz, DMSO-d6) δ 8.85 (s, 1H), 8.77 (s, 1H), 8.39 (dd, J=12.1, 8.3 Hz, 1H), 7.83 (dd, J=11.0, 7.1 Hz, 1H), 3.94 (s, 3H).

Intermediate 2h: 3-(2,5-dichloropyrimidin-4-yl)-1-methyl-5-fluoro-1H-indole

##STR00053##

The compound was synthesized in the same manner as those in Intermediate 2a. MS m/z: 296 [M+1], 297, 298.

¹H NMR (400 MHz, CDCl₃) δ 8.49 (s, 1H), 8.46 (s, 1H), 8.46-8.42 (m, 1H), 7.34 (dd, J=8.9, 4.4 Hz, 1H), 7.14 (td, J=8.9, 2.6 Hz, 1H), 3.94 (s, 3H).

Intermediate 2i: 3-(2-chloro-5-fluoropyrimidin-4-yl)-1-methyl-1H-indole

##STR00054##

The compound was synthesized in the same manner as those in Intermediate 2a with a yield of 73%. MS m/z: 262 [M+1], 264.

¹H NMR (400 MHz, DMSO-d6) δ 8.69 (d, J=3.7 Hz, 1H), 8.54 (dd, J=7.2, 1.2 Hz, 1H), 8.39 (d, J=3.0 Hz, 1H), 7.62 (d, J=7.5 Hz, 1H), 7.41-7.30 (m, 2H), 3.96 (s, 3H).

Intermediate 2j: 3-(2-chloro-5-fluoropyrimidin-4-yl)-1-methyl-5-fluoro-1H-indole

##STR00055##

The compound was synthesized in the same manner as those in Intermediate 2a with a yield of 77%. MS m/z: 280 [M+1], 282.

¹H NMR (400 MHz, DMSO-d6) δ 8.71 (d, J=3.5 Hz, 1H), 8.45 (d, J=2.8 Hz, 1H), 8.20 (dd, J=10.3, 2.5 Hz, 1H), 7.66 (dd, J=8.9, 4.5 Hz, 1H), 7.30-7.16 (m, 1H), 3.96 (s, 3H).

Intermediate 2k: 3-(2-chloro-5-fluoropyrimidin-4-yl)-1-methyl-5,6-difluoro-1H-indole

##STR00056##

The compound was synthesized in the same manner as those in Intermediate 2a. MS m/z: 298 [M+1], 300.

¹H NMR (400 MHz, CDCl₃) δ 8.56 (dd, J=11.4, 8.1 Hz, 1H), 8.36 (d, J=3.3 Hz, 1H), 8.01 (d, J=2.6 Hz, 1H), 7.19 (dd, J=10.1, 6.6 Hz, 1H), 3.90 (s, 3H).

Intermediate 2:

The tumor growth curves of three experimental groups are shown in FIG. 1, and the mice's weight growth curves are shown in FIG. 2. The results show that the compounds of the present invention have a good inhibition effect on the growth of subcutaneously transplanted tumors of human lung cancer H1975-bearing nude mice, while having little effect on the weights of nude mice, and showing a good safety.

All of the literatures mentioned herein are incorporated into the present application by reference. It should be also noted that, upon reading the above mentioned contents of the present application, a person skilled in the art can modify, change or amend the present invention without departing from the spirits of the present invention, and these equivalents are also within the scope as defined by the claims appended in the present application.

Claims

1. A compound represented by the following general formula (I), or a pharmaceutically acceptable salt thereof,

2. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein Ring A is heteroaryl.

3. The compound according to claim 2 or a pharmaceutically acceptable salt thereof, wherein Ring A is indolyl, indazolyl, pyrro[2,3-c]pyridinyl pyrrolo[2,3-c]pyridinyl, pyrro[3,2-c]pyridinyl pyrrolo[3,2-c]pyridinyl, pyrro[2,3-b]pyridinyl pyrrolo[2,3-b]pyridinyl, pyrro[3,2-b]pyridinyl pyrrolo[3,2-b]pyridinyl, pyrro[2,3-b]pyrazinyl pyrrolo[2,3-b]pyrazinyl, indolin-2-onyl, pyridinyl, pyrazolyl or pyrimidinyl.

4. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein R₁ is hydrogen, halogen or haloC₁-C₄alkyl.

5. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein R₂ is C₁-C₄alkyl or haloC₁-C₄alkyl.

6. The compound according to claim 5 or a pharmaceutically acceptable salt thereof, wherein R₂ is C₂-C₄alkyl or haloC₂-C₄alkyl.

7. The compound according to claim 6 or a pharmaceutically acceptable salt thereof, wherein R₂ is isopropyl or trifluoroethyl.

8. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein R₄ is

9. The compound according to claim 8 or a pharmaceutically acceptable salt thereof, wherein R₄ is

10. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein R₃ is selected from a group consisting of

halogen, —CN, —NO₂, C₁-C₄alkyl, haloC₁-C₄alkyl, —C(O)R₇, —C(O)NR₇R₇′, —OR₇, —NHR₇, —NR₇—(C₁-C₄alkyl), —NR₇(CH₂)_nC(O)R₆ or —NR₆R₇,

or heterocycloalkyl that is unsubstituted or substituted with 1-3 substituents selected from halogen, C₁-C₄alkyl, haloC₁-C₄alkyl, —(CH₂)_nOH, —NR₇R₇′, —OR₇ or —C(O)R₇;

wherein, R₆ is —(CH₂)_qOR₇, —(CH₂)_qNR₇R₇′, —(CH₂)_qC(O)R₇ or —(CH₂)_qC(O)NR₇R₇′;

R₇ and R₇′ are each independently hydrogen, C₁-C₄alkyl or haloC₁-C₄alkyl, or R₇, R₇′ and the nitrogen atom attached thereto are cyclized together to form a heterocycloalkyl;

n is 0, 1, 2, 3 or 4;

q is 0, 1, 2, 3 or 4.

11. The compound according to claim 10 or a pharmaceutically acceptable salt thereof, wherein R₃ is —NR₆R₇, in which R₆ is —(CH₂)_qNR₇R₇′, R₇ and R₇′ are each independently hydrogen or C₁-C₄alkyl, q is 2.

12. The compound according to claim 10 or a pharmaceutically acceptable salt thereof, wherein R₃ is a heterocycloalkyl substituted by one substituent selected from halogen, C₁-C₄alkyl, haloC₁-C₄alkyl or —NR₇R₇′, R₇ and R₇′ are each independently hydrogen or C₁-C₄alkyl.

13. The compound according to claim 12 or a pharmaceutically acceptable salt thereof, wherein said heterocycloalkyl is pyrrolidinyl.

14. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein each R₅ is dependently independently halogen, C₁-C₄alkyl, haloC₁-C₄alkyl, —OR₇, —NR₇R₇′, —CN or —NO₂, R₇ and R₇′ are each independently hydrogen or C₁-C₄alkyl, m is 1, 2 or 3.

15. The compound according to claim 14 or a pharmaceutically acceptable salt thereof, wherein each R₅ is dependently independently halogen, C₁-C₄alkyl, —OR₇ or —NR₇R₇′, R₇ and R₇′ are each independently hydrogen or C₁-C₄alkyl, m is 1, 2 or 3.

16. The compound according to claim 1 or a pharmaceutically acceptable salt thereof, wherein said compound is selected from a group consisting of:

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-chloro-[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-(2,2,2-trifluoroethoxyl)-5-{[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino)pyridin-3-yl}acrylamide;

N-(2-{[2-(dimethylamino)ethyl](methyl)amino}-6-(2,2,2-trifluoroethoxyl)-5-{5-chloro-[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[4-(1-methyl-5-fluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[4-(1-methyl-5,6-difluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-chloro-[4-(1-methyl-6-fluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-chloro-[4-(1-methyl-5,6-difluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-chloro-[4-(1-methyl-5-fluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-fluoro-[4-(1-methyl-5-fluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-fluoro-[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-fluoro-[4-(1-methyl-5,6-difluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[4-(1-methyl-6-fluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-(2,2,2-trifluoroethoxyl)-5-{5-fluoro-[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide; and

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-(2,2,2-trifluoroethoxyl)-5-{[4-(1-methyl-5-fluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-chloro-[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide methanesulfonate;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{5-chloro-[4-(1-methyl-5,6-difluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide methanesulfonate;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[4-(1-methyl-5,6-difluoro-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide methanesulfonate;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[5-chloro-4-(1-methyl-1H-pyrro[2,3-b]pyridin-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[5-chloro-4-(1-methyl-1H-pyrro[2,3-b]pyridin-5-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[5-chloro-4-(1-methyl-1H-pyrazol-4-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide;

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[5-chloro-2′-methoxy-(4,5′-bipyrimidine)-2-yl]amino}pyridin-3-yl}acrylamide; and

N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-isopropyloxy-5-{[5-chloro-2′-amino-(4,5′-bipyrimidine)-2-yl]amino}pyridin-3-yl}acrylamide.

17. A process for preparing the compound represented by the general formula (I) of claim 1, comprising the steps of:

18. A pharmaceutical composition, comprising the compound represented by formula (I) of claim 1 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier, excipient or diluent.

19. A method for treating an EGFR activating or resistant mutation mediated lung cancer in a mammal, said method comprises administering to a mammal the compound represented by formula (I) of claim 1 or a pharmaceutically acceptable salt thereof, or a pharmaceutical composition comprising a therapeutically effective amount of a compound represented by formula (I) of claim 1 or a pharmaceutically acceptable salt thereof and a pharmaceutically acceptable carrier, excipient or diluent.

20. A method for selectively inhibiting an EGFR activating or resistant mutation over a wild-type EGFR, said method comprises contacting a biological sample with or administering to a lung cancer patient the compound represented by formula (I) of claim 1 or a pharmaceutically acceptable salt thereof or a pharmaceutical composition containing the same.

21. The method of claim 19, wherein the mammal is a human.

22. A compound, wherein said compound is N-{2-{[2-(dimethylamino)ethyl](methyl)amino}-6-(2,2,2-trifluoroethoxyl)-5-{[4-(1-methyl-1H-indol-3-yl)pyrimidin-2-yl]amino}pyridin-3-yl}acrylamide or a pharmaceutically acceptable salt thereof.