HETEROAROMATIC CHALCONE DERIVATIVES AND THEIR MEDICAL USE

Abstract

The present invention relates to heteroaromatic chalcone derivatives, particularly the compounds of formula (I) as described and defined herein, pharmaceutical compositions comprising these compounds, and their medical use, including their use in the treatment or prevention of cancer and, in particular, in the treatment or prevention of hematologic malignancies.

##STR00001##

Claims

1. A compound of formula (I) ##STR00077## wherein: R.sup.1 is C.sub.2-6 alkoxy; each R.sup.2 is independently selected from C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, —OH, —O(C.sub.1-6 alkyl), —O(C.sub.1-6 alkyl)-OH, —O(C.sub.1-6 alkyl)-O(C.sub.1-6 alkyl), —SH, —S(C.sub.1-6 alkyl), —S(C.sub.1-6 alkyl)-SH, —S(C.sub.1-6 alkyl)-S(C.sub.1-6 alkyl), —NH.sub.2, —NH(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), halogen, —CF.sub.3, —CN, —NO.sub.2, —N.sub.3, —CHO, —CO—(C.sub.1-6 alkyl), —COOH, —CO—O—(C.sub.1-6 alkyl), —O—CO—(C.sub.1-6 alkyl), —CO—NH.sub.2, —CO—NH(C.sub.1-6 alkyl), —CO—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—CO—(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)-CO—(C.sub.1-6 alkyl), —SO.sub.2—NH.sub.2, —SO.sub.2—NH(C.sub.1-6 alkyl), —SO.sub.2—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—SO.sub.2—(C.sub.1-6 alkyl), or —N(C.sub.1-6 alkyl)-SO.sub.2—(C.sub.1-6 alkyl); each R.sup.3 is independently selected from C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, —OH, —O(C.sub.1-6 alkyl), —O(C.sub.1-6 alkyl)-OH, —O(C.sub.1-6 alkyl)-O(C.sub.1-6 alkyl), —SH, —S(C.sub.1-6 alkyl), —S(C.sub.1-6 alkyl)-SH, —S(C.sub.1-6 alkyl)-S(C.sub.1-6 alkyl), —NH.sub.2, —NH(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), halogen, —CF.sub.3, —CN, —NO.sub.2, —N.sub.3, —CHO, —CO—(C.sub.1-6 alkyl), —COOH, —CO—O—(C.sub.1-6 alkyl), —O—CO—(C.sub.1-6 alkyl), —CO—NH.sub.2, —CO—NH(C.sub.1-6 alkyl), —CO—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—CO—(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)-CO—(C.sub.1-6 alkyl), —SO.sub.2—NH.sub.2, —SO.sub.2—NH(C.sub.1-6 alkyl), —SO.sub.2—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—SO.sub.2—(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)-SO.sub.2—(C.sub.1-6 alkyl), optionally substituted aryl or optionally substituted heteroaryl, wherein said aryl or said heteroaryl is optionally substituted with one or more groups independently selected from C.sub.1-4 alkyl, halogen, —CF.sub.3, —CN, —OH, —O(C.sub.1-4 alkyl), —NH.sub.2, —NH(C.sub.1-4 alkyl), or —N(C.sub.1-4 alkyl)(C.sub.1-4 alkyl); B is benzoheteroaryl, wherein the heteroaryl moiety comprised in said benzoheteroaryl is a monocyclic heteroaryl moiety having 5 ring atoms, wherein 1 or 2 ring atoms are each independently selected from oxygen, sulfur or nitrogen and the other ring atoms are carbon atoms; m is an integer of 0 to 4; and n is an integer of 0 to 4; or a pharmaceutically acceptable salt, solvate or prodrug thereof.

2. The compound of claim 1, wherein R.sup.1 is ethoxy.

3. The compound of claim 1 or 2, wherein R.sup.1 is in ortho-position with respect to the carbonyl group.

4. The compound of any one of claims 1 to 3, wherein each R.sup.2 is independently selected from C.sub.1-4 alkyl, halogen, —CF.sub.3, —CN, —OH, —O(C.sub.1-4 alkyl), —NH.sub.2, —NH(C.sub.1-4 alkyl), or —N(C.sub.1-4 alkyl)(C.sub.1-4 alkyl).

5. The compound of any one of claims 1 to 4, wherein each R.sup.3 is independently selected from C.sub.1-4 alkyl, halogen, —CF.sub.3, —CN, —OH, —O(C.sub.1-4 alkyl), —NH.sub.2, —NH(C.sub.1-4 alkyl), or —N(C.sub.1-4 alkyl)(C.sub.1-4 alkyl).

6. The compound of any one of claims 1 to 5, wherein B is benzoheteroaryl, wherein the heteroaryl moiety comprised in said benzoheteroaryl is a monocyclic heteroaryl moiety having 5 ring atoms, wherein 1 or 2 ring atoms are each independently selected from oxygen, sulfur or nitrogen and the other ring atoms are carbon atoms, and further wherein said benzoheteroaryl is attached to the remainder of the compound of formula (I) via the heteroaryl moiety comprised in said benzoheteroaryl.

7. The compound of any one of claims 1 to 6, wherein B is indolyl, benzo[b]thienyl, or benzofuranyl.

8. The compound of any one of claims 1 to 7, wherein B is 1H-indol-2-yl, 1H-indol-3-yl, 2-benzo[b]thienyl, 3-benzo[b]thienyl, benzofuran-2-yl, or benzofuran-3-yl.

9. The compound of claim 1, wherein said compound is a compound of one of the following formulae 13 to 15, 18 to 29 or 31 to 33: ##STR00078## ##STR00079## ##STR00080## or a pharmaceutically acceptable salt, solvate or prodrug thereof.

10. The compound of claim 1, which is a compound of the following formula 15: ##STR00081## or a pharmaceutically acceptable salt or solvate thereof.

11. A pharmaceutical composition comprising the compound of any one of claims 1 to 10 and a pharmaceutically acceptable excipient.

12. The compound of any one of claims 1 to 10 or the pharmaceutical composition of claim 11 for use as a medicament.

13. The compound of any one of claims 1 to 10 or the pharmaceutical composition of claim 11 for use in the treatment or prevention of cancer.

14. The compound for use according to claim 13 or the pharmaceutical composition for use according to claim 13, wherein the cancer is hematological cancer.

15. The compound for use according to claim 14 or the pharmaceutical composition for use according to claim 14, wherein the hematological cancer is selected from Hodgkin's disease, non-Hodgkin's lymphoma, follicular non-Hodgkin's lymphoma, mantle cell lymphoma, diffuse non-Hodgkin's lymphoma, diffuse large B-cell lymphoma, Burkitt's tumor, peripheral or cutaneous T-cell lymphoma, mycosis fungoides, Sézary's disease, T-zone lymphoma, lymphoepithelioid lymphoma, Lennert's lymphoma, peripheral T-cell lymphoma, lymphosarcoma, a malignant immunoproliferative disease, Waldenström's macroglobulinaemia, alpha heavy chain disease, gamma heavy chain disease, Franklin's disease, an immunoproliferative small intestinal disease, Mediterranean disease, multiple myeloma, Kahler's disease, myelomatosis, plasma cell leukemia, lymphoid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, subacute lymphocytic leukemia, prolymphocytic leukemia, hairy-cell leukemia, leukemic reticuloendotheliosis, adult T-cell leukemia, myeloid leukemia, acute myeloid leukemia, chronic myeloid leukemia, subacute myeloid leukemia, myeloid sarcoma, chloroma, granulocytic sarcoma, acute promyelocytic leukemia, acute myelomonocytic leukemia, a chronic BCR-ABL negative myeloproliferative disorder, polycythaemia vera, essential thrombocythemia, idiopathic myelofibrosis, monocytic leukemia, acute erythraemia, erythroleukemia, acute erythraemic myelosis, Di Guglielmo's disease, chronic erythraemia, Heilmeyer-Schöner disease, acute megakaryoblastic leukemia, mast cell leukemia, acute panmyeiosis, acute myeiofibrosis, or Letterer-Siwe disease.

16. The compound for use according to claim 13 or the pharmaceutical composition for use according to claim 13, wherein the cancer is selected from breast cancer, genitourinary cancer, prostate tumor, hormone-refractory prostate tumor, lung cancer, small cell lung tumor, non-small cell lung tumor, gastrointestinal cancer, hepatocellular carcinoma, colorectal tumor, colon cancer, gastric cancer, epidermoid cancer, epidermoid head and/or neck tumor, mouth tumor, melanoma, ovarian cancer, pancreas cancer, neuroblastoma, bladder cancer, renal cancer, or brain cancer.

17. The compound for use according to any one of claims 13 to 16 or the pharmaceutical composition for use according to any one of claims 13 to 16, wherein the compound or the pharmaceutical composition is to be administered in combination with an anticancer drug and/or in combination with radiotherapy.

18. Use of the compound of any one of claims 1 to 10 in the preparation of a medicament for the treatment or prevention of cancer.

19. The use of claim 18, wherein the cancer is hematological cancer.

20. The use of claim 19, wherein the hematological cancer is selected from Hodgkin's disease, non-Hodgkin's lymphoma, follicular non-Hodgkin's lymphoma, mantle cell lymphoma, diffuse non-Hodgkin's lymphoma, diffuse large B-cell lymphoma, Burkitt's tumor, peripheral or cutaneous T-cell lymphoma, mycosis fungoides, Sézary's disease, T-zone lymphoma, lymphoepithelioid lymphoma, Lennert's lymphoma, peripheral T-cell lymphoma, lymphosarcoma, a malignant immunoproliferative disease, Waldenström's macroglobulinaemia, alpha heavy chain disease, gamma heavy chain disease, Franklin's disease, an immunoproliferative small intestinal disease, Mediterranean disease, multiple myeloma, Kahler's disease, myelomatosis, plasma cell leukemia, lymphoid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, subacute lymphocytic leukemia, prolymphocytic leukemia, hairy-cell leukemia, leukemic reticuloendotheliosis, adult T-cell leukemia, myeloid leukemia, acute myeloid leukemia, chronic myeloid leukemia, subacute myeloid leukemia, myeloid sarcoma, chloroma, granulocytic sarcoma, acute promyelocytic leukemia, acute myelomonocytic leukemia, a chronic BCR-ABL negative myeloproliferative disorder, polycythaemia vera, essential thrombocythemia, idiopathic myelofibrosis, monocytic leukemia, acute erythraemia, erythroleukemia, acute erythraemic myelosis, Di Guglielmo's disease, chronic erythraemia, Heilmeyer-Schöner disease, acute megakaryoblastic leukemia, mast cell leukemia, acute panmyelosis, acute myelofibrosis, or Letterer-Siwe disease.

21. The use of claim 18, wherein the cancer is selected from breast cancer, genitourinary cancer, prostate tumor, hormone-refractory prostate tumor, lung cancer, small cell lung tumor, non-small cell lung tumor, gastrointestinal cancer, hepatocellular carcinoma, colorectal tumor, colon cancer, gastric cancer, epidermoid cancer, epidermoid head and/or neck tumor, mouth tumor, melanoma, ovarian cancer, pancreas cancer, neuroblastoma, bladder cancer, renal cancer, or brain cancer.

22. The use of any one of claims 18 to 21, wherein the medicament is to be administered in combination with an anticancer drug and/or in combination with radiotherapy.

23. A method of treating cancer, the method comprising the administration of the compound of claim 1 to a subject in need thereof.

24. The method of claim 23, wherein the cancer is hematological cancer.

25. The method of claim 24, wherein the hematological cancer is selected from the group consisting of Hodgkin's disease, non-Hodgkin's lymphoma, follicular non-Hodgkin's lymphoma, mantle cell lymphoma, diffuse non-Hodgkin's lymphoma, diffuse large B-cell lymphoma, Burkitt's tumor, peripheral or cutaneous T-cell lymphoma, mycosis fungoides, Sézary's disease, T-zone lymphoma, lymphoepithelioid lymphoma, Lennert's lymphoma, peripheral T-cell lymphoma, lymphosarcoma, a malignant immunoproliferative disease, Waldenström's macroglobulinaemia, alpha heavy chain disease, gamma heavy chain disease, Franklin's disease, an immunoproliferative small intestinal disease, Mediterranean disease, multiple myeloma, Kahler's disease, myelomatosis, plasma cell leukemia, lymphoid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, subacute lymphocytic leukemia, prolymphocytic leukemia, hairy-cell leukemia, leukemic reticuloendotheliosis, adult T-cell leukemia, myeloid leukemia, acute myeloid leukemia, chronic myeloid leukemia, subacute myeloid leukemia, myeloid sarcoma, chloroma, granulocytic sarcoma, acute promyelocytic leukemia, acute myelomonocytic leukemia, a chronic BCR-ABL negative myeloproliferative disorder, polycythaemia vera, essential thrombocythemia, idiopathic myelofibrosis, monocytic leukemia, acute erythraemia, erythroleukemia, acute erythraemic myelosis, Di Guglielmo's disease, chronic erythraemia, Heilmeyer-Schöner disease, acute megakaryoblastic leukemia, mast cell leukemia, acute panmyelosis, acute myelofibrosis, and Letterer-Siwe disease.

26. The method of claim 23, wherein the cancer is selected from the group consisting of breast cancer, genitourinary cancer, prostate tumor, hormone-refractory prostate tumor, lung cancer, small cell lung tumor, non-small cell lung tumor, gastrointestinal cancer, hepatocellular carcinoma, colorectal tumor, colon cancer, gastric cancer, epidermoid cancer, epidermoid head and/or neck tumor, mouth tumor, melanoma, ovarian cancer, pancreas cancer, neuroblastoma, bladder cancer, renal cancer, and brain cancer.

27. The method of claim 23, wherein the method comprises administering the compound in combination with an anticancer drug and/or in combination with radiotherapy.

28. The method of claim 23, wherein the subject is a human.

Description

[0071] The invention is also illustrated by the following illustrative figures. The appended figures show:

[0072] FIG. 1: Structure-activity relationship (SAR) studies based on the lead compound 1 were obtained by structural modifications of rings A and B and resulted in compound 15 as new hit compound. The cytotoxic impact of the compounds 1 and 15 on three malignant hematological cell lines (MEC1, U-2940 and OCI-Ly7) as well as the mouse fibroblast cell line (M2-10B4) used in the lead structure optimization process are shown.

[0073] FIG. 2: Cytotoxic effect of compound 15 on a variety of hematologic cell lines. CCRF, Jurkat: T-cell acute lymphoblastic leukemia; HL60, K562: myeloid leukemia; SU-DHL6, SU-DHL9: B-cell lymphoma. Viability was determined as described in the methods section in Example 2 and normalized to cells incubated with vehicle only.

[0074] FIG. 3: Comparison of cytotoxic efficacies of compound 15 and fludarabine in 3 cell lines of the B-cell lineage. (A) MEC1; (B) U-2940; (C) OCI-Ly7. Results were normalized to incubations with vehicle only. IC.sub.50 values (μM) were 0.022 and 42.34 (MEC1), 0.052 and 1.95 (U-2940), 2.9 and 105.5 (OCI-Ly7) for compound 15 and fludarabine, respectively.

[0075] FIG. 4: Comparison of cytotoxic efficacies of compound 15 and fludarabine in primary cells. (A) Peripheral blood mononuclear cells (PBMC) of chronic lymphocytic leukemia (CLL) patients (N=15) tested in suspension culture; (B) PBMC of healthy individuals (N=4) in suspension culture; (C) PBMC of CLL patients (N=9) cultured over a layer of mouse fibroblast cells (M2-10B4). Results were normalized to incubations with vehicle only. IC.sub.50 values are listed in Table 4 (see Example 2).

[0076] FIG. 5: Combination treatment of CLL primary cells with compound 15 (referred to as “APG38” in this Figure) together with a further anticancer agent (ABT199, CAL101 or PCI32765); see Example 3. (A) Impact of ABT199 alone and in combination with compound 15 on the viability of primary cells from CLL patients (N=5). Cells were incubated in triplicates for 48 h before viability was determined. Mean values and standard deviations are shown. (B) Impact of CAL101 alone and in combination with compound 15 on the viability of primary cells from CLL patients (N=6). Cells were incubated in triplicates for 48 h before viability was determined. Mean values and standard deviations are shown. Since the x-axis has a logarithmic scale, the vehicle only incubation (=origin−“0”) with the 100% viability reference point is not depicted. (C) impact of CAL101 alone and in combination with compound 15 on the viability of primary cells from CLL patients (N=6). Cells were incubated in triplicates for 48 h before viability was determined. Mean values and standard deviations are shown. Since the x-axis has a logarithmic scale, the vehicle only incubation (=origin−“0”) with the 100% viability reference point is not depicted.

[0077] The present invention particularly relates to the following items:

[0078] 1. A compound of formula (I)

##STR00008## [0079] wherein: [0080] R.sup.1 is C.sub.2-6 alkoxy; [0081] each R.sup.2 is independently selected from C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, —OH, —O(C.sub.1-6 alkyl), —O(C.sub.1-6 alkyl)-OH, —O(C.sub.1-6 alkyl)-O(C.sub.1-6 alkyl), —SH, —S(C.sub.1-6 alkyl), —S(C.sub.1-6 alkyl)-SH, —S(C.sub.1-6 alkyl)-S(C.sub.1-6 alkyl), —NH.sub.2, —NH(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), halogen, —CF.sub.3, —CN, —NO.sub.2, —N.sub.3, —CHO, —CO—(C.sub.1-6 alkyl), —COOH, —CO—O—(C.sub.1-6 alkyl), —O—CO—(C.sub.1-6 alkyl), —CO—NH.sub.2, —CO—NH(C.sub.1-6 alkyl), —CO—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—CO—(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)-CO—(C.sub.1-6 alkyl), —SO.sub.2—NH.sub.2, —SO.sub.2—NH(C.sub.1-6 alkyl), —SO.sub.2—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—SO.sub.2—(C.sub.1-6 alkyl), or —N(C.sub.1-6 alkyl)-SO.sub.2—(C.sub.1-6 alkyl); [0082] each R.sup.3 is independently selected from C.sub.1-6 alkyl, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, —OH, —O(C.sub.1-6 alkyl), —O(C.sub.1-6 alkyl)-OH, —O(C.sub.1-6 alkyl)-O(C.sub.1-6 alkyl), —SH, —S(C.sub.1-6 alkyl), —S(C.sub.1-6 alkyl)-SH, —S(C.sub.1-6 alkyl)-S(C.sub.1-6 alkyl), —NH.sub.2, —NH(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), halogen, —CF.sub.3, —CN, —NO.sub.2, —N.sub.3, —CHO, —CO—(C.sub.1-6 alkyl), —COOH, —CO—O—(C.sub.1-6 alkyl), —O—CO—(C.sub.1-6 alkyl), —CO—NH.sub.2, —CO—NH(C.sub.1-6 alkyl), —CO—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—CO—(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)-CO—(C.sub.1-6 alkyl), —SO.sub.2—NH.sub.2, —SO.sub.2—NH(C.sub.1-6 alkyl), —SO.sub.2—N(C.sub.1-6 alkyl)(C.sub.1-6 alkyl), —NH—SO.sub.2—(C.sub.1-6 alkyl), —N(C.sub.1-6 alkyl)-SO.sub.2—(C.sub.1-6 alkyl), optionally substituted aryl or optionally substituted heteroaryl, wherein said aryl or said heteroaryl is optionally substituted with one or more groups independently selected from C.sub.1-4 alkyl, halogen, —CF.sub.3, —CN, —OH, —O(C.sub.1-4 alkyl), —NH.sub.2, —NH(C.sub.1-4 alkyl), or —N(C.sub.1-4 alkyl)(C.sub.1-4 alkyl); [0083] B is benzoheteroaryl, wherein the heteroaryl moiety comprised in said benzoheteroaryl is a monocyclic heteroaryl moiety having 5 ring atoms, wherein 1 or 2 ring atoms are each independently selected from oxygen, sulfur or nitrogen and the other ring atoms are carbon atoms; [0084] m is an integer of 0 to 4; and [0085] n is an integer of 0 to 4; [0086] or a pharmaceutically acceptable salt, solvate or prodrug thereof.

[0087] 2. The compound of item 1, wherein R.sup.1 is ethoxy.

[0088] 3. The compound of item 1 or 2, wherein R.sup.1 is in ortho-position with respect to the carbonyl group.

[0089] 4. The compound of any one of items 1 to 3, wherein each R.sup.2 is independently selected from C.sub.1-4 alkyl, halogen, —CF.sub.3, —CN, —OH, —O(C.sub.1-4 alkyl), —NH.sub.2, —NH(C.sub.1-4 alkyl), or —N(C.sub.1-4 alkyl)(C.sub.1-4 alkyl).

[0090] 5. The compound of any one of items 1 to 4, wherein each R.sup.3 is independently selected from C.sub.1-4 alkyl, halogen, —CF.sub.3, —CN, —OH, —O(C.sub.1-4 alkyl), —NH.sub.2, —NH(C.sub.1-4 alkyl), or —N(C.sub.1-4 alkyl)(C.sub.1-4 alkyl).

[0091] 6. The compound of any one of items 1 to 5, wherein B is benzoheteroaryl, wherein the heteroaryl moiety comprised in said benzoheteroaryl is a monocyclic heteroaryl moiety having 5 ring atoms, wherein 1 or 2 ring atoms are each independently selected from oxygen, sulfur or nitrogen and the other ring atoms are carbon atoms, and further wherein said benzoheteroaryl is attached to the remainder of the compound of formula (I) via the heteroaryl moiety comprised in said benzoheteroaryl.

[0092] 7. The compound of any one of items 1 to 6, wherein B is indolyl, benzo[b]thienyl, or benzofuranyl.

[0093] 8. The compound of any one of items 1 to 7, wherein B is 1H-indol-2-yl, 1H-indol-3-yl, 2-benzo[b]thienyl, 3-benzo[b]thienyl, benzofuran-2-yl, or benzofuran-3-yl.

[0094] 9. The compound of item 1, wherein said compound is a compound of one of the following formulae 13 to 15, 18 to 29 or 31 to 33:

##STR00009## ##STR00010## ##STR00011## [0095] or a pharmaceutically acceptable salt, solvate or prodrug thereof.

[0096] 10. A pharmaceutical composition comprising the compound of any one of items 1 to 9 and a pharmaceutically acceptable excipient.

[0097] 11. The compound of any one of items 1 to 9 or the pharmaceutical composition of item 10 for use as a medicament.

[0098] 12. The compound of any one of items 1 to 9 or the pharmaceutical composition of item 10 for use in the treatment or prevention of cancer.

[0099] 13. A method of treating or preventing cancer, the method comprising the administration of the compound of any one of items 1 to 9 or the pharmaceutical composition of item 10 to a subject in need thereof.

[0100] 14. The compound for use according to item 12 or the pharmaceutical composition for use according to item 12 or the method of item 13, wherein the cancer is hematological cancer.

[0101] 15. The compound for use according to item 14 or the pharmaceutical composition for use according to item 14 or the method of item 14, wherein the hematological cancer is selected from Hodgkin's disease, non-Hodgkin's lymphoma, follicular non-Hodgkin's lymphoma, mantle cell lymphoma, diffuse non-Hodgkin's lymphoma, diffuse large B-cell lymphoma, Burkitt's tumor, peripheral or cutaneous T-cell lymphoma, mycosis fungoides, Sézary's disease, T-zone lymphoma, lymphoepitheiioid lymphoma, Lennert's lymphoma, peripheral T-cell lymphoma, lymphosarcoma, a malignant immunoproliferative disease, Waldenström's macroglobulinaemia, alpha heavy chain disease, gamma heavy chain disease, Franklin's disease, an immunoproliferative small intestinal disease, Mediterranean disease, multiple myeloma, Kahler's disease, myelomatosis, plasma cell leukemia, lymphoid leukemia, acute lymphoblastic leukemia, chronic lymphocytic leukemia, subacute lymphocytic leukemia, prolymphocytic leukemia, hairy-cell leukemia, leukemic reticuloendotheliosis, adult T-cell leukemia, myeloid leukemia, acute myeloid leukemia, chronic myeloid leukemia, subacute myeloid leukemia, myeloid sarcoma, chloroma, granulocytic sarcoma, acute promyelocytic leukemia, acute myelomonocytic leukemia, a chronic BCR-ABL negative myeloproliferative disorder, polycythaemia vera, essential thrombocythemia, idiopathic myelofibrosis, monocytic leukemia, acute erythraemia, erythroleukemia, acute erythraemic myelosis, Di Guglielmo's disease, chronic erythraemia, Heilmeyer-Schöner disease, acute megakaryoblastic leukemia, mast cell leukemia, acute panmyelosis, acute myelofibrosis, or Letterer-Siwe disease.

[0102] 16. The compound for use according to item 12 or the pharmaceutical composition for use according to item 12 or the method of item 13, wherein the cancer is selected from breast cancer, genitourinary cancer, prostate tumor, hormone-refractory prostate tumor, lung cancer, small cell lung tumor, non-small cell lung tumor, gastrointestinal cancer, hepatocellular carcinoma, colorectal tumor, colon cancer, gastric cancer, epidermoid cancer, epidermoid head and/or neck tumor, mouth tumor, melanoma, ovarian cancer, pancreas cancer, neuroblastoma, bladder cancer, renal cancer, or brain cancer.

[0103] 17. The compound for use according to any one of items 12 or 14 to 16 or the pharmaceutical composition for use according to any one of items 12 or 14 to 16 or the method of any one of items 13 to 16, wherein the compound or the pharmaceutical composition is to be administered in combination with an anticancer drug and/or in combination with radiotherapy.

[0104] 18. The method of any of items 13 to 17, wherein the subject is a human.

[0105] The invention will now be described by reference to the following examples which are merely illustrative and are not to be construed as a limitation of the scope of the present invention.

EXAMPLES

[0106] Unless stated otherwise, all chemicals were obtained from Sigma-Aldrich or Apollo Europe and were of analytical grade. Melting points were determined on a Kofler hot stage apparatus and are uncorrected. The .sup.1H and 13C NMR spectra were recorded on a BrukerAvance DPx200 (200 and 50 MHz). Chemical shifts are reported in δ units (ppm) relative to Me.sub.4Si line as internal standard and J values are reported in Hertz. Mass spectra were obtained by a Hewlett Packard (GC: 5890; MS: 5970) spectrometer. The purity of the synthesized compounds was established by combustion analysis with a Perkin-Elmer 2400 CHN elemental analyzer and was within +0.4%. Solutions in organic solvents were dried over anhydrous sodium sulphate.

Example 1: Synthesis of Chalcone Derivatives

[0107] Compounds 1 to 35 as described below, which include compounds of formula (I) according to the present invention as well as reference compounds, were prepared in accordance with the following general synthetic procedure (illustrated in Scheme 1 below):

General Synthetic Procedure

[0108] A solution of 2 mmol of the appropriate acetophenone derivative and 3 ml 50% NaOH in 5 ml ethanol was stirred at room temperature for 30 minutes. Then, 2 mmol of the corresponding aldehyde derivative, dissolved in 3 ml ethanol, were added and stirred at room temperature. After complete conversion of the starting materials (monitored by thin layer chromatography (TLC)), the reaction mixture was poured into ice water or extracted with ethyl acetate. The organic layer was dried over anhydrous Na.sub.2SO.sub.4 and evaporated. The so-obtained crude product was purified by column chromatography or by recrystallization in ethanol.

##STR00012##

Scheme 1:

[0109] Synthetic route to compounds 1-35. Reagents and conditions: 50% NaOH, EtOH, room temperature, 1-24 h.

3-(2-Napthyl)-1-(2-ethoxyphenyl)-2-propen-1-one (1)

[0110] ##STR00013##

[0111] Yield: 0.16 g (27%) yellow solid; mp: 96-97° C. .sup.1H NMR (CDCl.sub.3) δ 8.14-7.39 (m, 11H), 7.21-6.85 (m, 2H), 4.14 (q, J=6.9 Hz, 2H), 1.43 (t, J=6.9 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.7, 157.7, 142.6, 134.2, 133.4, 133.0, 132.8, 130.6, 130.3, 129.3, 128.6, 128.5, 127.7, 127.4, 127.1, 126.6, 123.6, 120.7, 112.6, 64.2, 14.8. MS m/z 302 (13%, M.sup.+), 287 (2%), 273 (3%), 151 (77%), 68 (100%). Anal Calcd for C.sub.21H.sub.18O.sub.2×0.2H.sub.2O. C, 82.44; H, 6.06. Found: C, 82.07; H, 5.62.

1-(2-Methoxyphenyl)-3-(2-naphthyl)-2-propen-1-one (2)

[0112] ##STR00014##

[0113] Yield: 0.35 g (60%) yellow solid; mp: 81-83° C. .sup.1H NMR (CDCl.sub.3) δ 7.96 (s, 1H), 7.91-7.70 (m, 5H), 7.65 (dd, J=7.6 Hz, J=1.6 Hz, 1H), 7.68-7.38 (m, 4H), 7.12-6.96 (m, 2H), 3.92 (s, 3H). .sup.13C NMR (CDCl.sub.3: δ 193.0, 158.1, 143.4, 134.2, 133.3, 132.8, 132.6, 130.4, 130.3, 129.3, 128.6, 128.5, 127.8, 127.2, 127.2, 126.6, 123.7, 120.7, 111.6, 55.8. MS m/z 288 (61%, M.sup.+), 287 (42%), 229 (39%), 152 (100%), 135 (47%). Anal Calcd for C.sub.20H.sub.16O.sub.2: C, 83.31; H, 5.59. Found: C, 83.07; H, 5.64.

3-(2-Naphthyl)-1-(2-propoxyphenyl)-2-propen-1-one (3)

[0114] ##STR00015##

[0115] Yield: 0.42 g (66%) yellow oil. .sup.1H NMR (CDCl.sub.3) δ 7.96 (s, 1H), 7.89-7.65 (m, 6H), 7.65-7.39 (m, 4H), 7.09-6.93 (m, 2H), 4.02 (t, J=6.4 Hz, 2H), 1.92-1.70 (m, 2H), 1.00 (t, J=7.4 Hz, 3H). .sup.13C NMR (CDCl.sub.3: δ 192.7, 157.8, 142.5, 134.2, 133.4, 133.0, 132.7, 130.6, 130.3, 129.4, 128.6, 128.5, 127.7, 127.5, 127.1, 126.6, 123.7, 120.6, 112.4, 70.1, 22.6, 10.7. MS m/z 316 (1%, M.sup.+), 141 (9%), 85 (27%), 43 (100%), 41 (20%). Anal Calcd for C.sub.22H.sub.20O.sub.2: C, 83.51; H, 6.37. Found: C, 83.11; H, 6.09.

1-(2-Butoxyphenvl)-3-(2-naphthyl)-2-propen-1-one (4)

[0116] ##STR00016##

[0117] Yield: 0.23 g (48%) yellow oil. .sup.1H NMR (CDCl.sub.3) δ 7.98 (s, 1H), 7.90-7.67 (m, 6H), 7.63 (s, 1H), 7.57-7.41 (m, 3H), 7.11-6.95 (m, 2H), 4.09 (t, J=6.3 Hz, 2H), 1.88-1.70 (m, 2H), 1.59-1.38 (m, 2H), 0.87 (t, J=7.3 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.7, 157.9, 142.5, 134.2, 133.4, 133.0, 132.8, 130.6, 130.3, 129.3, 128.6, 128.5, 127.8, 127.5, 127.1, 126.6, 123.7, 120.6, 112.4, 68.3, 31.3, 19.4, 13.7. MS m/z 330 (12%, M.sup.+), 273 (38%), 189 (45%), 141 (100%), 121 (41%). Anal Calcd for C.sub.23H.sub.22O.sub.2: C, 83.60; H, 6.71. Found: C, 83.17; H, 6.49.

3-(2-Naphthyl)-1-[2-(2-propanoyloxy)phenyl]-2-propen-1-one (5)

[0118] ##STR00017##

[0119] Yield: 0.48 g (76%) yellow solid; mp: 82-85° C. .sup.1H NMR (CDCl.sub.3) δ 7.98 (s, 1H), 7.91-7.40 (m, 10H), 7.09-6.96 (m, 2H), 4.66 (sept, J=7.0 Hz, 1H), 1.37 (d, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.9, 156.5, 142.2, 134.0, 133.3, 132.7, 130.6, 130.3, 130.2, 128.5, 128.4, 127.6, 127.4, 127.0, 126.5, 123.4, 120.6, 114.2, 71.0, 22.0. MS m/z 316 (25%, M+), 273 (82%), 154 (100%), 152 (95%), 43 (39%). Anal Calcd for C.sub.22H.sub.20O.sub.2×0.3H.sub.2O: C, 82.11; H, 6.45. Found: C, 82.05; H, 6.33.

1-(2-Methylphenyl)-3-(2-naphthyl)-2-propen-1-one (6)

[0120] ##STR00018##

[0121] Yield: 0.25 g (45%) yellow oil. .sup.1H NMR (CDCl.sub.3) δ 7.93 (s, 1H), 7.90-7.78 (m, 3H), 7.76-7.27 (m, 8H), 7.20 (s, 1H), 2.47 (s, 3H). .sup.13C NMR (CDCl.sub.3) δ 197.0, 146.6, 139.6, 137.4, 134.8, 133.7, 132.6, 131.8, 131.1, 130.9, 129.2, 129.1, 128.5, 128.3, 127.9, 127.3, 127.2, 125.9, 124.0, 20.7. MS m/z 272 (30%, M.sup.+), 141 (61%), 119 (100%), 91 (55%), 43 (37%). Anal Calcd for C.sub.20H.sub.16O: C, 88.20; H, 5.92. Found: C, 87.88; H, 5.66.

1-(2-Ethoxyphenyl)-3-(6-methoxy-2-naphthyl)-2-propen-1-one (7)

[0122] ##STR00019##

[0123] Yield: 0.46 g (68%) yellow solid; mp: 97-99° C. .sup.1H NMR (CDCl.sub.3) δ 67.90 (s, 1H), 7.84-7.64 (m, 5H), 7.60-7.39 (m, 2H), 7.20-7.10 (m, 2H), 7.08-6.94 (m, 2H), 4.13 (q, J=7.0 Hz, 2H), 3.92 (s, 3H), 1.43 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.9, 158.8, 157.6, 143.1, 135.7, 132.9, 130.7, 130.5, 130.2, 130.1, 129.5, 128.8, 127.5, 126.5, 124.4, 120.7, 119.4, 112.6, 106.0, 64.3, 55.4, 14.9. MS m/z 332 (39%, M.sup.+), 171 (100%), 139 (65%), 121 (61%), 65 (35%). Anal Calcd for C.sub.22H.sub.20O.sub.3: C, 79.50; H, 6.06. Found: C, 79.45; H, 5.86.

3-(3-Ethenylphenyl)-1-(2-ethoxyphenyl)-2-propen-1-one (8)

[0124] ##STR00020##

[0125] Yield: 0.31 g (56%) yellow oil. .sup.1H NMR (CDCl.sub.3) δ 7.72-7.24 (m, 8H), 7.08-6.91 (m, 2H), 6.74 (dd, J=17.6 Hz, J=10.8 Hz, 1H), 5.78 (dd, J=17.6 Hz, J=0.7 Hz, 1H), 5.29 (dd, J=10.8 Hz, J=0.7 Hz, 1H), 4.12 (q, J=7.0 Hz, 2H), 1.42 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.5, 157.6, 142.2, 138.1, 136.1, 135.4, 133.0, 130.5, 129.1, 129.0, 127.7, 127.4, 126.1, 120.6, 114.6, 112.5, 64.1, 14.8. MS m/z 278 (7%, M.sup.+), 161 (100%), 128 (36%), 121 (74%), 65 (23%). HRMS for C.sub.19H.sub.19O.sub.2: 279.1385. Found: 279.1389.

3-(1,3-Benzodioxol-5-yl)-1-(2-ethoxyphenyl)-2-propen-1-one (9)

[0126] ##STR00021##

[0127] Yield: 0.29 g (49%) brown solid; mp: 65-70° C. .sup.1H NMR (CDCl.sub.3) δ 7.69-7.27 (m, 4H), 7.13-6.92 (m, 4H), 6.86-6.77 (m, 1H), 6.00 (s, 2H), 4.13 (q, J=7.0 Hz, 2H), 1.43 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.6, 157.6, 149.5, 148.3, 142.5, 132.8, 130.5, 129.7, 129.5, 125.4, 124.8, 120.7, 112.6, 108.6, 106.5, 101.5, 64.2, 14.9. MS m/z 296 (4%, M.sup.+), 149 (19%), 135 (29%), 121 (25%), 43 (100%). Anal Calcd for C.sub.18H.sub.16O.sub.6×0.5H.sub.2O: C, 70.81; H, 5.60. Found: C, 70.82; H, 5.35.

1-(2-Ethoxyphenyl)-3-(1-naphthyl)-2-propen-1-one (10)

[0128] ##STR00022##

[0129] Yield: 0.47 g (78%) yellow solid; mp: 109-110° C. .sup.1H NMR (CDCl.sub.3) δ 8.57-8.42 (m, 1H), 8.30-8.28 (m, 1H), 7.95-7.78 (m, 3H), 7.77-7.68 (m, 1H), 7.64-7.38 (m, 5H), 7.11-6.92 (m, 2H), 4.13 (q, J=7.0 Hz, 2H), 1.42 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.6, 157.7, 139.3, 133.7, 133.1, 132.6, 131.7, 130.7, 130.3, 129.7, 129.3, 128.7, 126.7, 126.2, 125.4, 124.9, 123.6, 120.7, 112.6, 64.2, 14.8. MS m/z 302 (40%, M.sup.+), 152 (88%), 141 (54%), 121 (98%), 43 (100%). Anal Calcd for C.sub.21H.sub.18O.sub.2×0.25toluene: C, 83.97; H, 6.20. Found: C, 84.00; H, 5.82.

3-(9-Anthranyl)-1-(2-ethoxyphenyl)-2-propen-1-one (11)

[0130] ##STR00023##

[0131] Yield: 0.54 g (76%) yellow solid; mp: 93-96° C. .sup.1H NMR (CDCl.sub.3) δ 8.66-8.51 (m, 1H), 8.44-8.25 (m, 3H), 8.05-7.91 (m, 2H), 7.81-7.72 (m, 1H), 7.55-7.34 (m, 6H), 7.12-6.99 (m, 1H), 6.98-6.88 (m, 1H), 4.08 (q, J=6.9 Hz, 2H), 1.34 (t, J=6.9 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.5, 157.7, 139.7, 135.7, 133.2, 131.3, 130.7, 130.4, 129.5, 129.3, 128.8, 128.1, 126.1, 125.5, 125.3, 120.8, 112.4, 64.2, 14.8. MS m/z 352 (31%, M.sup.+), 202 (65%), 149 (61%), 121 (100%), 65 (21%). Anal Calcd for C.sub.25H.sub.20O.sub.2×0.14H.sub.2O: C, 84.60; H, 5.76. Found: C, 84.62; H, 5.52.

1-(2-Ethoxyphenyl)-3-(9-phenanthrenyl)-2-propen-1-one (12)

[0132] ##STR00024##

[0133] Yield: 0.38 g (54%) yellow solid; mp: 117-120° C. .sup.1H NMR (CDCl.sub.3) δ 8.78-8.61 (m, 2H), 8.54-8.41 (m, 1H), 8.33-8.21 (m, 1H), 8.06 (s, 1H), 7.94-7.84 (m, 1H), 7.80-7.59 (i, 6H), 7.57-7.41 (m, 1H), 7.12-6.94 (m, 2H), 4.18 (q, J=6.9 Hz, 2H), 1.48 (t, J=6.9 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.5, 157.8, 140.0, 133.2, 131.8, 131.2, 131.0, 130.7, 130.4, 130.3, 129.3, 129.1, 127.5, 127.0, 126.9, 126.4, 124.5, 123.1, 122.6, 120.8, 112.6, 64.3, 14.9. MS m/z 352 (49%, M.sup.+), 202 (83%), 191 (46%), 121 (100%), 57 (53%). Anal Calcd for C.sub.25H.sub.20O.sub.2: C, 85.20; H, 5.72. Found: C, 85.05; H, 5.44.

3-(5-Benzo[b]thienyl)-1-(2-ethoxyphenyl)-2-propen-1-one (13)

[0134] ##STR00025##

[0135] Yield: 0.090 g (14%) yellow solid; mp: 104-106° C. .sup.1H NMR (CDCl.sub.3) δ 8.03-7.97 (m, 1H), 7.94-7.33 (m, 8H), 7.10-6.94 (m, 2H), 4.15 (q, J=7.0 Hz, 2H), 1.44 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.8, 157.7, 142.9, 140.1, 132.9, 131.7, 130.6, 129.5, 127.5, 126.9, 124.6, 124.1, 123.2, 122.9, 120.7, 112.6, 64.3, 14.9. MS m/z 308 (11%, M.sup.+), 279 (14%), 161 (38%), 147 (100%), 121 (37%), 65 (21%). Anal Calcd for C.sub.19H.sub.16O.sub.2S×0.15H.sub.2O: C, 73.36; H, 5.28. Found: C, 73.44; H, 4.95.

3-(1-Benzothien-3-yl)-1-(2-ethoxyphenyl)-2-propen-1-one (14)

[0136] ##STR00026##

[0137] Yield: 0.39 g (63%) yellow oil. .sup.1H NMR (CDCl.sub.3) δ 8.13-7.81 (m, 3H), 7.80-7.56 (m, 3H), 7.50-7.33 (m, 3H), 7.10-6.90 (m, 2H), 4.12 (q, J=7.0 Hz, 2H), 1.41 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.3, 157.7, 140.5, 137.3, 134.1, 133.1, 132.5, 130.7, 129.2, 128.3, 127.4, 125.0, 124.8, 122.9, 122.2, 120.7, 112.6, 64.2, 14.8. MS m/z 308 (43%, M.sup.+), 147 (100%), 121 (98%), 43 (89%), 41 (30%). Anal Calcd for C.sub.19H.sub.16O.sub.2S: C, 74.00; H, 5.23. Found: C, 73.71; H, 4.92.

1-(2-Ethoxyphenyl)-3-(1H-indole-2-yl)-2-propen-1-one (15)

[0138] ##STR00027##

[0139] Yield: 0.22 g (38%) brown solid; mp: 124-126° C. .sup.1H NMR (CDCl.sub.3) δ 9.05 (sbr, 1H), 7.72-7.54 (m, 3H), 7.49-6.89 (m, 7H), 6.87-6.80 (m, 1H), 4.08 (q, J=7.0 Hz, 2H), 1.37 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 192.9, 157.4, 138.0, 134.3, 133.3, 132.8, 130.3, 129.2, 128.5, 124.9, 124.5, 121.4, 120.6, 120.4, 112.6, 111.3, 108.8, 64.3, 14.7. MS m/z 291 (63%, M+), 262 (42%), 130 (61%), 119 (100%), 91 (49%). Anal Calcd for C.sub.19H.sub.17NO.sub.2: C, 78.33; H, 5.88; N, 4.81. Found: C, 78.24; H, 5.67; N, 4.79.

3-(2-Napthyl)-1-(3-ethoxyphenyl)-2-propen-1-one (16)

[0140] ##STR00028##

[0141] Yield: 0.21 g (34%) yellow solid; mp: 97-100° C. .sup.1H NMR (CDCl.sub.3) δ 8.03-7.76 (m, 6H), 7.66-6.37 (m, 6H), 7.15-7.05 (m, 1H), 4.12 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 190.4, 159.4, 145.0, 139.8, 134.6, 133.5, 132.6, 130.8, 129.8, 128.9, 128.8, 128.0, 127.5, 126.9, 123.9, 122.4, 121.1, 119.8, 113.8, 63.9, 15.0. MS m/z 302 (100%, M.sup.+), 181 (36%), 152 (84%), 128 (18%), 65 (15%). Anal Calcd for C.sub.21H.sub.18O.sub.2. C, 83.42; H, 6.00. Found: C, 83.12; H, 5.95.

3-(2-Napthyl)-1-(4-ethoxyphenyl)-2-propen-1-one (17)

[0142] ##STR00029##

[0143] Yield: 0.44 g (73%) yellow solid; mp: 159-161° C. .sup.1H NMR (CDCl.sub.3) δ 8.09-7.48 (m, 11H), 6.97 (d, J=8.8 Hz, 2H), 4.11 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 188.8, 163.0, 144.1, 134.4, 133.5, 132.8, 131.1, 131.0, 130.6, 128.8, 128.8, 127.9, 127.4, 126.9, 123.9, 122.2, 114.5, 63.9, 14.9. MS m/z 302 (99%, M.sup.+), 273 (36%), 152 (100%), 121 (59%), 65 (37%). Anal Calcd for C.sub.21H.sub.18O.sub.2. C, 83.42; H, 6.00. Found: C, 83.07; H, 5.87.

3-(1-Benzothien-3-yl)-1-(3-ethoxyphenyl)-2-propen-1-one (18)

[0144] ##STR00030##

[0145] Yield: 0.21 g (34%) yellow solid; mp: 103-106° C. .sup.1H NMR (CDCl.sub.3) δ 8.15-8.07 (m, 2H), 7.92-7.88 (m, 2H), 7.65-7.38 (m, 6H), 7.16-7.11 (m, 1H), 4.12 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 190.3, 159.5, 140.7, 139.7, 137.5, 136.5, 132.5, 129.8, 128.9, 125.3, 125.2, 123.3, 122.7, 122.4, 121.0, 119.9, 113.8, 63.9, 15.0. MS m/z 308 (60%, M.sup.+), 279 (26%), 187 (48%), 115 (100%), 69 (56%). Anal Calcd for C.sub.19H.sub.16O.sub.2S: C, 74.00; H, 5.23. Found: C, 73.99; H, 4.87.

3-(1-Benzothien-3-yl)-1-(4-ethoxyphenyl)-2-propen-1-one (19)

[0146] ##STR00031##

[0147] Yield: 0.45 g (74%) yellow solid; mp: 129-130° C. .sup.1H NMR (CDCl.sub.3) δ 8.14-8.04, (m, 4H), 7.92-7.88 (m, 2H), 7.65 (AB-system, J.sub.AB=15.6 Hz, 1H), 7.50-7.41 (m, 2H), 7.00-6.96 (m, 2H), 4.12 (q, J=7.0 Hz, 2H), 1.46 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 188.7, 163.1, 140.7, 137.6, 132.7, 131.1, 131.0, 128.3, 125.3, 125.2, 123.2, 122.5, 122.4, 114.5, 64.0, 14.9. MS m/z 308 (100%, M.sup.+), 279 (27%), 251 (25%), 115 (35%), 65 (10%). Anal Calcd for C.sub.19H.sub.16O.sub.2S×0.13H.sub.2O: C, 73.44; H, 5.27. Found: C, 73.24; H, 4.87.

1-(3-Ethoxyphenyl)-3-(1H-indole-2-yl)-2-propen-1-one (20)

[0148] ##STR00032##

[0149] Yield: 0.18 g (31%) brown solid; mp: 156-158° C. .sup.1H NMR (CDCl.sub.3) δ 8.99 (s, 1H), 7.85 (d, J=15.6 Hz, 1H), 7.65-7.07 (m, 9H), 6.91 (s, 1H), 4.03 (q, J=7.0 Hz, 2H), 1.40 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ190.3, 159.4, 139.7, 135.0, 134.3, 129.8, 128.7, 125.1, 121.9, 121.0, 120.9, 119.9, 119.6, 113.7, 111.5, 110.3, 63.9, 14.9. MS m/z 291 (100%, M.sup.+), 262 (71%), 234 (49%), 170 (35%), 115 (32%). Anal Calcd for C.sub.19H.sub.17NO.sub.2: C, 78.33; H, 5.88. Found: C, 78.20; H, 5.56.

1-(4-Ethoxyphenyl)-3-(1H-indole-2-yl)-2-propen-1-one (21)

[0150] ##STR00033##

[0151] Yield: 0.09 g (15%) brown solid; mp: 178-181° C. .sup.1H NMR (CDCl.sub.3) δ 8.83 (sbr, 1H), 8.03-6.90 (m, 11H), 4.07 (q, J=7.0 Hz, 2H), 1.43 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3) δ 188.5, 163.1, 138.1, 134.0, 131.0, 130.9, 128.8, 125.0, 121.8, 120.9, 119.5, 114.5, 111.4, 109.8, 64.0, 14.9. MS m/z 291 (100%, M.sup.+), 262 (43%), 234 (29%), 117 (44%), 65 (30%). Anal Calcd for C.sub.19H.sub.17NO.sub.2: C, 78.33; H, 5.88, N, 4.81. Found: C, 78.18; H, 5.40, N, 4.77.

(E)-1-(2-Ethoxyphenyl)-3-(1H-indol-5-yl)-2-propen-1-one (22)

[0152] ##STR00034##

[0153] Yield: 0.26 g (45%) yellow solid; mp: 151-153° C. .sup.1H NMR (CDCl.sub.3): δ 8.48 (s, 1H), 7.89-7.80 (m, 2H), 7.69-7.60 (m, 1H), 7.54-7.34 (m, 4H), 7.28-7.19 (m, 1H), 7.09-6.94 (m, 2H), 6.62-6.54 (m, 1H), 4.13 (q, J=6.9 Hz, 2H), 1.42 (t, J=6.9 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 193.5, 157.4, 145.4, 137.1, 132.4, 130.3, 129.9, 128.2, 127.2, 125.3, 124.6, 122.8, 121.8, 120.6, 112.6, 111.6, 103.4, 64.3, 14.8. MS m/z 291 (18%, M.sup.+), 130 (93%), 69 (100%), 55 (72%), 43 (87%). Anal. Calcd for C.sub.19H.sub.17NO.sub.2: C, 78.33; H, 5.88; N, 4.81. Found: C, 78.23; H, 5.68; N, 4.73.

(E)-1-(3-Ethoxyphenyl)-3-(1H-indol-5-yl)-2-propen-1-one (23)

[0154] ##STR00035##

[0155] Yield: 0.11 g (19%); mp: 121-123° C. .sup.1H NMR (CDCl.sub.3): δ 7.31-8.76 (m, 9H), 7.08-7.13 (m, 1H), 6.60 (d, J=3.2 Hz, 1H), 5.70 (s, 1H), 4.10 (q, J=7.0 Hz, 2H), 1.43 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 190.9, 159.3, 147.3, 140.3, 137.3, 129.7, 128.4, 127.1, 125.5, 123.3, 122.2, 121.0, 119.5 (2C), 113.7, 111.8, 103.7, 63.9, 15.0. MS m/z 291 (100%, M.sup.+), 262 (23%), 170 (73%), 117 (82%), 65 (35%). Anal. Calcd for C.sub.19H.sub.17NO.sub.2:C, 78.33; H, 5.88; N, 4.81. Found: C, 77.92; H, 5.51; N, 4.70.

(E)-1-(4-Ethoxyphenyl)-3-(1H-indol-5-yl)-2-propen-1-one (24)

[0156] ##STR00036##

[0157] Yield: 0.35 g (60%); mp: 171-173° C. .sup.1H NMR (DMSO-d.sub.6): δ 11.40 (s, 1H), 8.22-8.08 (m, 3H), 7.88 (s, 2H), 7.73 (d, J=8.0 Hz, 1H), 7.49 (m, 2H), 7.09 (d, J=8.8 Hz, 2H), 6.55 (d, J=2.6 Hz, 1H), 4.17 (q, J=7.0 Hz, 2H), 1.40 (t, J=7.0 Hz, 3H). .sup.13C NMR (DMSO-d.sub.6): δ 187.2, 162.2, 145.6, 137.3, 130.7, 130.7, 127.9, 126.6, 126.0, 122.8, 121.5, 118.2, 114.3, 111.9, 102.1, 63.5, 14.5. MS m/z 291 (100%, M+), 262 (49%), 170 (40%), 117 (46%), 65 (48%). Anal. Calcd for C.sub.19H.sub.17NO.sub.2 0.1 mol EtOH: C, 77.92; H, 5.99; N, 4.73. Found: C, 77.56; H, 5.69; N, 4.73.

(E)-3-(1H-indol-5-yl)-1-(2-propoxyphenyl)-2-propen-1-one (25)

[0158] ##STR00037##

[0159] Yield: 0.35 g (57%) brown solid; mp: 114-116° C. .sup.1H NMR (CDCl.sub.3): δ 10.2 (s, 1H), 7.89-7.34 (m, 7H), 7.28-7.19 (m, 1H), 7.09-6.95 (m, 2H), 6.58-6.49 (m, 1H), 4.03 (t, J=6.4 Hz, 2H), 1.93-1.71 (m, 2H), 1.00 (t, J=7.4 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 193.0, 157.1, 145.3, 137.1, 132.1, 129.8, 129.5, 127.8, 126.1, 125.4, 123.8, 122.4, 120.8, 120.1, 112.1, 111.6, 102.2, 69.7, 22.2, 10.3. MS m/z 305 (14%, M.sup.+), 262 (15%), 130 (100%), 115 (36%), 43 (19%). Anal. Calcd for C.sub.20H.sub.19NO.sub.2: C, 78.66; H, 6.27; N, 4.59. Found: C, 78.58; H, 6.04; N, 4.54.

(E)-3-(1H-indol-2-yl)-1-(2-propoxyphenyl)-2-propen-1-one (26)

[0160] ##STR00038##

[0161] Yield: 0.20 g (32%) yellow solid; mp: 112-114° C. .sup.1H NMR (CDCl.sub.3): δ 8.7 (s, 1H), 7.73-7.57 (s, 3H), 7.51-7.31 (m, 4H), 7.30-6.93 (m, 3H), 6.90-6.82 (m, 1H), 4.01 (t, J=6.4 Hz, 2H), 1.90-1.70 (m, 2H), 1.00 (t, J=7.4 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 192.6, 157.6, 137.9, 134.3, 132.9, 132.8, 130.4, 129.3, 128.6, 124.9, 124.5, 121.5, 120.7, 120.5, 112.5, 111.2, 109.0, 70.2, 22.6, 10.7. MS m/z 305 (37%, M.sup.+), 130 (55%), 115 (39%), 69 (100%), 43 (99%). Anal. Calcd for C.sub.20H.sub.19NO.sub.2: C, 78.66; H, 6.27; N, 4.59. Found: C, 78.52; H, 6.07; N, 4.53.

(E)-3-(1-Benzothiophen-2-yl)-1-(2-ethoxyphenyl)-2-propen-1-one (27)

[0162] ##STR00039##

[0163] Yield: 0.32 g (51%) orange solid; mp: 95-98° C. .sup.1H NMR (CDCl.sub.3): δ 7.95-7.82 (m, 1H), 7.81-7.69 (m, 3H), 7.52-7.30 (m, 5H), 7.08-6.90 (m, 2H), 4.13 (q, J=7.0 Hz, 2H), 1.49 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 191.2, 158.0, 140.9, 140.0, 139.8, 135.0, 133.4, 130.8, 129.1, 128.7, 128.5, 126.1, 124.8, 124.3, 122.4, 120.7, 112.5, 64.2, 14.9. MS m/z 308 (20%, M.sup.+), 147 (83%), 69 (100%), 43 (100%), 41 (73%). Anal. Calcd for C.sub.19H.sub.16O.sub.2S: C, 74.00; H, 5.23. Found: C, 74.04; H, 5.08.

(E)-3-(1-Benzothiophen-2-yl)-1-(3-ethoxyphenyl)-2-propen-1-one (28)

[0164] ##STR00040##

[0165] Yield: 0.49 g (79%); mp: 98-99° C. .sup.1H NMR (CDCl.sub.3): δ 8.05 (d, J=1.4 Hz, 1H), 7.99-7.88 (m, 2H), 7.68-7.37 (m, 7H), 7.15-7.09 (m, 1H), 4.12 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 190.4, 159.4, 145.3, 142.0, 140.4, 139.8, 131.5, 129.7, 127.8, 124.9, 123.5, 123.1, 121.8, 121.1, 119.8, 113.8, 63.9, 15.0. MS m/z 308 (69%, M.sup.+), 307 (60%), 187 (45%), 115 (100%), 65 (44%). Anal. Calcd for C.sub.19H.sub.16O.sub.2S: C, 74.00; H, 5.23. Found: C, 73.84; H, 4.88.

(E)-3-(1-Benzothiophen-2-yl)-1-(4-ethoxyphenyl)-2-propen-1-one (29)

[0166] ##STR00041##

[0167] Yield: 0.46 g (74%); mp: 149-151° C. .sup.1H NMR (CDCl.sub.3): δ 8.09-8.07 (m, 3H), 8.03-7.87 (m, 2H), 7.68-7.58 (m, 2H), 7.48 (A-part of an AB-system, J.sub.AB=5.6 Hz, 1H), 7.37 (B-part of an AB-system, J.sub.AB=5.6 Hz, 1H), 7.00-6.93 (m, 2H), 4.11 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 188.8, 163.0, 144.4, 141.7, 140.2, 131.6, 131.2, 131.0, 127.7, 124.8, 124.3, 123.5, 123.0, 121.5, 114.4, 63.9, 14.9. MS m/z 308 (100%, M.sup.+), 307 (61%), 279 (40%), 115 (38%), 65 (9%). Anal. Calcd for C.sub.19H.sub.16O.sub.2S: C, 74.00; H, 5.23. Found: C, 73.73; H, 4.82.

(E)-3-(2,2′-bithiophen-5-yl)-1-(2-ethoxyphenyl)-2-propen-1-one (30)

[0168] ##STR00042##

[0169] Yield: 0.32 g (47%) brown oil. .sup.1H NMR (CDCl.sub.3): δ 7.80-7.65 (m, 2H), 7.50-7.38 (m, 1H), 7.36-7.15 (m, 4H), 7.14-7.08 (m, 1H), 7.07-6.90 (m, 3H), 4.13 (q, J=7.0 Hz, 2H), 1.47 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 191.5, 157.8, 140.1, 139.5, 136.8, 134.6, 133.1, 132.7, 130.7, 129.0, 128.0, 125.9, 125.6, 124.7, 124.5, 120.7, 112.5, 64.2, 14.9. MS m/z 340 (38%, M.sup.+), 179 (100%), 147 (20%), 121 (36%), 57 (56%). Anal. Calcd for C.sub.19H.sub.16O.sub.2S.sub.2: C, 67.03; H, 4.74. Found: C, 66.73; H, 4.39.

(E)-3-(1-Benzofuran-2-yl)-1-(2-ethoxyphenyl)-2-propen-1-one (31)

[0170] ##STR00043##

[0171] Yield: 0.35 g (60%) yellow solid; mp: 79-81° C. .sup.1H NMR (CDCl.sub.3): δ 7.78-7.62 (m, 2H), 7.61-7.16 (m, 6H), 7.08-6.91 (m, 3H), 4.14 (q, J=7.0 Hz, 2H), 1.46 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 191.6, 158.0, 155.4, 153.4, 133.3, 130.6, 128.9, 128.5, 127.5, 126.2, 123.2, 121.6, 120.6, 112.6, 111.3, 111.2, 64.3, 14.6. MS m/z 292 (16%, M.sup.+), 131 (100%), 121 (37%), 115 (35%), 65 (18%). Anal. Calcd for C.sub.19H.sub.16O.sub.3: C, 78.06; H, 5.52. Found: C, 77.58; H, 5.25.

(E)-3-(1-Benzofuran-2-yl)-1-(3-ethoxyphenyl)-2-propen-1-one (32)

[0172] ##STR00044##

[0173] Yield: 0.33 g (56%); mp: 127-129° C. .sup.1H NMR (CDCl.sub.3): δ 7.70-7.58 (m, 5H), 7.55-7.50 (m, 1H), 7.46-7.34 (m, 2H), 7.29-7.21 (m, 1H), 7.16-7.10 (m, 1H), 7.03 (s, 1H), 4.13 (q, J=7.0 Hz, 2H), 1.46 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 189.5, 159.5, 155.8, 153.2, 139.5, 131.0, 129.8, 128.7, 126.9, 123.6, 122.2, 122.0, 121.2, 120.1, 113.7, 112.7, 111.6, 63.9, 15.0. MS m/z 292 (100%, M+), 235 (44%), 207 (22%), 171 (45%), 115 (58%). Anal. Calcd for C.sub.19H.sub.16O.sub.3: C, 78.06; H, 5.52. Found: C, 77.83; H, 5.22.

(E)-3-(1-Benzofuran-2-yl)-1-(4-ethoxyphenyl)-2-propen-1-one (33)

[0174] ##STR00045##

[0175] Yield: 0.43 g (74%); mp: 100-101° C. .sup.1H NMR (CDCl.sub.3): δ 8.11-8.05 (m, 2H), 7.79-7.70 (m, 2H), 7.62-7.50 (m, 2H), 7.41-7.21 (m, 2H), 7.00-6.94 (m, 3H), 4.12 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 187.9, 163.2, 155.7, 153.4, 131.1, 130.9, 130.2, 128.8, 126.7, 123.5, 122.1, 122.0, 114.5, 112.2, 111.5, 64.0, 14.9. MS m/z 292 (100%, M+), 264 (30%), 235 (36%), 171 (28%), 121 (54%). Anal. Calcd for C.sub.19H.sub.16O.sub.3: C, 78.06; H, 5.52. Found: C, 77.83; H, 5.16.

(E)-3-(1,3-benzodioxol-5-yl)-1-(3-ethoxyphenyl)prop-2-en-1-one (34)

[0176] ##STR00046##

[0177] Yield: 0.49 g (83%); mp: 119-120° C. .sup.1H NMR (CDCl.sub.3): δ 87.73 (d, J=15.0 Hz, 1H), 7.60-7.51 (m, 2H), 7.43-7.30 (m, 2H), 7.17-7.08 (m, 3H), 6.84 (d, J=8.0 Hz, 1H), 6.03 (s, 2H), 4.11 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 190.3, 159.4, 150.1, 148.6, 144.8, 139.9, 129.7, 129.5, 125.4, 121.0, 120.3, 119.7, 113.7, 108.8, 106.8, 101.8, 63.9, 15.0. MS m/z 296 (100%, M.sup.+), 267 (22%), 145 (33%), 89 (37%), 65 (30%). Anal. Calcd for C.sub.18H.sub.16O.sub.4: C, 72.96; H, 5.44. Found: C, 72.72; H, 4.99.

(E)-3-(1,3-benzodioxol-5-yl)-1-(3-ethoxyphenyl)prop-2-en-1-one (35)

[0178] ##STR00047##

[0179] Yield: 0.44 g (75%); mp: 98-100° C. .sup.1H NMR (CDCl.sub.3): δ 8.01 (d, J=6.7 Hz, 2H), 7.72 (A-part of an AB-system, J.sub.AB=15.4 Hz, 1H), 7.38 (B-part of an AB-system, J.sub.AB=15.4 Hz, 1H), 7.17-7.09, (m, 2H), 6.99-6.92 (m, 2H), 6.83 (d, J=8.0 Hz, 1H), 6.02 (s, 2H), 4.11 (q, J=7.0 Hz, 2H), 1.45 (t, J=7.0 Hz, 3H). .sup.13C NMR (CDCl.sub.3): δ 188.7, 162.9, 149.9, 148.5, 143.9, 131.2, 130.9, 129.7, 125.2, 120.1, 114.4, 108.8, 106.8, 101.7, 63.9, 14.9. MS m/z 296 (100%, M.sup.+), 267 (41%), 121 (35%), 89 (25%), 65 (25%). Anal. Calcd for C.sub.18H.sub.16O.sub.4: C, 72.96; H, 5.44. Found: C, 72.77; H, 4.98.

Example 2: Structure-Activity Relationship (SAR)-Guided Development of Potent Antitumor Compounds

Materials and Methods

Cell Lines and Patients

[0180] Hematological cell lines were acquired from the Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (www.dsmz.de). Sixteen patients diagnosed with chronic lymphocytic leukemia at the Division of Hematology and Hemostaseology at the Vienna General Hospital and four healthy donors were included in the study. All participants signed informed consent according to the Declaration of Helsinki (Ethics Committee Nr: EK 1722/2012). Peripheral blood mononuclear cells (PBMC) were isolated using standardized Ficoll-Hypaque gradient centrifugation (Seromed, Berlin, Germany) and stored in liquid nitrogen until use.

Cell Culture

[0181] JURKAT and CCRF-CEM (T-cell acute lymphoblastic leukemia), HL60 and K562 representing acute and chronic myeloid leukemia, respectively, the chronic lymphocytic leukemia cell line MEC-1, and the diffuse large B-cell lymphoma cell line U-2940 were cultured in Gibco RPMI 1640+GlutaMAX (Life Technologies, Carlsbad, Calif., USA) supplemented with 10% fetal bovine serum gold (FBS gold; PAA Laboratories, Pasching, Austria) and 1% PenStrep (100 U/ml penicillin and 100 μg/ml streptomycin; PAA Laboratories), and maintained at 37° C. in humidified atmosphere with 5% CO.sub.2. The diffuse large B-cell lymphoma cell line OCI-LY7 was cultured in Gibco IMDM+GlutaMAX and 25 mM HEPES (Life Technologies) containing 20% FBS gold and 1% PenStrep.

Primary Cells

[0182] Primary cells were thawed in Gibco RPMI 1640+L-glutamine (PAA Laboratories) supplemented with 20% FBS gold and cultured overnight at standard conditions before cells were incubated with the compounds.

Viability Tests

[0183] All experiments with hematological cell lines were done using phenol red-free RPMI 1640+L-glutamine (PAA Laboratories) supplemented with 1% PenStrep and 10% FBS gold, except experiments with OCI-Ly7 which were carried out in Gibco IMEM+GlutaMAX and 25 mM HEPES containing 20% FBS gold and 1% PenStrep. Cells were incubated in triplicates with increasing concentrations of the compounds for 48 h, changes in viability were determined using the cell proliferation and cytotoxicity assays EZ4U (Biomedica Group, Austria) and CellTiter-Blue Cell Viability Assay (Promega, Madison, Wis., USA) following instructions of the manufacturers. IC.sub.50 values were calculated from two independent experiments using GraphPad Prism 5 software.

[0184] Primary cells were incubated at a density of 300,000 cells per well in 96-well plates in a total volume of 100 μl of Gibco RPMI 1640+L-glutamine (PAA Laboratories) supplemented with 20% FBS gold with increasing concentrations of compounds for 48 h. For co-culture experiments, 150,000 M2-10B4 mouse fibroblast cells were seeded into 12-well plates and allowed to form a confluent layer over night. Supernatant was replaced by 3 million primary cells in a total volume of 1 ml medium and incubated with increasing concentrations of compounds for 48 h. Viability was measured using CellTiter-Blue Cell Viability Assay (Promega, Madison, Wis., USA) following the instructions of the manufacturers. Experiments with primary cells were done in triplicates, IC.sub.50 values were calculated from the mean values of all samples used in the various experiments using GraphPad Prism 5 software.

Results and Conclusions

[0185] In an initial screening of an in-house library the compound 3-(2-napthyl)-1-(2-ethoxyphenyl)-2-propen-1-one (1) was identified as a highly potent cytotoxic agent with IC.sub.50 values in the nanomolar range. As initial screening panel the three cell lines MEC1 (chronic lymphocytic leukemia), U-2940 (diffuse large B-cell lymphoma) and OCI-Ly7 (Non-Hodgkin lymphoma) representing B-cell neoplasms were used.

[0186] Structurally seen, the small molecule compound 1 represents a typical chalcone scaffold. It is characterized by an ortho-ethoxy-substituted phenyl part as ring A and a 2-naphthyl moiety symbolizing ring B. The focus of the present study was to guide the systematic identification of a growth inhibitor with specificity to neoplastic cells, as cytotoxicity towards healthy cells is mostly associated with adverse effects, which can be related to morbidity and mortality of the patient (Milligan D W et al. Brit J Haematol 2006, 135, 450-474). To discriminate in vitro between structural elements necessary for potent cytotoxicity towards tumor cells which, at the same time, clearly show less activity on normal cells, the compounds were additionally tested on the murine bone marrow fibroblast cell line M2-10B4. This cell line is regularly used as feeder layer when cultured with patient cells providing additional support and survival signals in particular in drug screens (Kurtova A V et al. Blood 2009, 114, 4441-4450).

[0187] Beginning with compound 1 as lead, the inventors first started with homologous variation of the 2-alkoxy substituent of ring A. In a second step, the ring B site of compound 1 was replaced and optimized (see FIG. 1). In a last set of compounds the inventors focused on the substitution pattern of ring A with respect to the ethoxy group. Three triplets including the most active compounds were generated and biologically investigated. All the compounds were obtained by base-catalyzed reaction of the corresponding acetophenone with an appropriate benzaldehyde derivative (Claisen-Schmidt condensation), as also described in Example 1 and shown in Scheme 1 above.

[0188] Initially, compounds were biologically tested in six concentration steps (0.1 μM; 1 μM; 5 μM; 10 μM; 50 μM; and 100 μM) using the CellTiter-Blue Cell Viability Assay (Promega, Madison, Wis., USA) and an incubation time of 48 hours. In case of a highly active compound (IC.sub.50<1 μM) the tested concentration range was shifted to 0.005 μM, 0.01 μM, 0.05 μM and 0.1 μM to define the IC.sub.50 more precisely. IC.sub.50 values were calculated from at least two independent experiments with 3 replicates each. In order to evaluate the biologic activity of the new compounds, cytotoxicity was compared to that of fludarabine, an already approved drug for the treatment of various B-cell malignancies. The cytotoxic potential (IC.sub.50) of fludarabine was 42.34 μM in MEC1, 1.95 μM in U-2940, and 105.50 μM in OCI-Ly7 cells, respectively. Differences in IC.sub.50 values for the different cell types can be explained by the biological and genetic particularities of each subtype of B-cell Non-Hodgkin lymphoma (Stacchini A et al. Leukemia Res 1999, 23, 127-136; Sambade C et al. Int J Cancer 2006, 118, 555-563; Chang H et al. Leukemia lymphoma 1995, 19, 165-171; Tweeddale M E et al. Blood 1987, 69, 1307-1314; Tweeddale M et al. Blood 1989, 74, 572-578).

First Optimization Step

[0189] Compound 1 was used as lead structure to study the influence of the ortho-ethoxy group with respect to the biological activity. The inventors kept the 3-(2-naphthyl)-1-phenyl-2-propen-1-one backbone and started to systematically vary the substituents of ring A in position 2. Hence, the first derivatives synthesized represented the homologous series of the alkoxy substituent and started with methoxy, followed by propoxy and butoxy. The biological data (see Table 1 below) clearly showed the significance of this structural element: the methoxy derivative 2 demonstrated an almost 10-fold loss of activity on MEC1 and OCI-Ly7 cells (0.43 μM and 0.46 μM) and half of the activity towards U-2940 (4.09 μM) although the unwanted cytotoxic potential on M2-10B4 (IC.sub.50 41.79 μM) was reduced. Elongation of the ethoxy group of compound 1 by one more methylene group to obtain the n-propoxy derivative 3 represented only half of the cytotoxic potency on the malignant kind of cell lines (0.13 μM, 5.31 μM and 0.10 μM vs. 0.06 μM, 2.43 μM and 0.06 μM). The compound did not show any activity on the mouse fibroblast cell line up to 100 μM. The inhibition of cell growth demonstrated clear SAR depending on the length of the alkoxy chain as n-butoxy (compound 4) showed reduced activity compared to the n-propoxy compound 3. Compound 5 with an isopropoxy residue presented even weaker activity than compounds 2 and 3. Moreover, using methyl instead of an alkoxy substituent like it is the case in compound 6, the inhibitory activity on all three malignant cell lines decreased further to the lower micromolar range (6.36 μM, 10.34 μM and 4.92 μM) and also a cytotoxic potential towards M2-10B4 was observed (72.00 μM). With regard to the biological activity, already small changes of the 2-substituent of ring A considerably influenced the inhibitory activity with ethoxy being the most favorable structural feature.

Second Optimization Step

[0190] As outlined above and illustrated in FIG. 1, the second optimization step focused on a replacement of ring B. The presence of a 6-methoxy substituent on the naphthyl part (compound 7) resulted in a cell line dependent loss of activity with no cytotoxic potential on M2-10B4 cells. Further modifications of the naphthyl moiety led to compound 8 with a “dissected” aromatic ring. The vinylphenyl derivative was almost equipotent in killing U-2940 cells (2.50 μM) but less active on MEC1 and OCI-Ly7 (0.20 μM and 0.50 μM) as compared to compound 1 and did not show any activity on mouse fibroblasts. Further variations of ring B included a benzodioxole moiety (compound 9) as well as the 1-naphthyl congener of derivative 1, compound 10. Both modifications exhibited lower activity on MEC1 (1.10 μM and 1.90 μM), U-2940 (9.49 μM and 7.37 μM) and OCI-Ly7 (0.13 μM and 1.48 μM). Compound 10 showed an IC.sub.50 value of 14.05 μM on M2-10B4 which is half as much as compound 1 (7.80 μM). The insertion of a third phenyl ring led in case of the anthracene derivative 11 to a complete loss of activity (up to 50 μM) towards all of the four cell lines whereas when having a phenanthrene moiety (compound 12) the cytotoxic activity on the malignant cell lines was retained even though a little bit lower compared to compound 1 (MEC1 1.63 μM, U2940 39.90 μM and OCI-Ly7 0.06 μM). Introduction of 5-thionaphthene and 3-thionaphthene (compound 13 and 14), respectively, resulted in a 10-fold loss of cytotoxic activity in MEC1 and OCI-Ly7 cells whereas regarding U-2940 the 3-thionaphthene 14 (0.86 μM) proved to be more potent than its congener 13 (9.05 μM). This fact applies also for the healthy fibroblasts: compound 13 (21.12 μM) shows lower and compound 14 (8.20 μM) similar activity than the lead compound 1 (7.80 μM). In compound 15 the 2-naphthyl was replaced by a 2-indole ring system which presented an improvement of the biological activity on the malignant cell lines (MEC 0.02 μM, U2940 2.90 μM and OCI-Ly7 0.05 μM). Interestingly, the compound showed less cytotoxic potential on healthy cells (19.15 μM) in comparison to compound 1 (7.80 μM). Together, from steps 1 and 2 compound 15 resulted as hit with respect to hematological B-cell malignancies.

TABLE-US-00001 TABLE 1 Cytotoxic activity of the compounds 1-15 on three malignant hematological cell lines (MEC1, U-2940 and OCI-Ly7) as well as the mouse fibroblast cell line (M2-10B4). For comparison, IC.sub.50 values (in μM) upon incubation with fludarabine, an approved drug for hematologic malignancies, were 42.34 (MEC1), 1.95 (U-2940), 105.50 (OCI-Ly7), and >100 (M2-10B4), respectively. [00048] IC.sub.50 [μM] Compound R MEC1 U-2940 OCI-Ly7 M2-10B4 1 OC.sub.2H.sub.5 0.06 2.43 0.06   7.80 2 OCH.sub.3 0.43 4.09 0.46  41.79 3 OC.sub.3H.sub.7 0.13 5.31 0.10 >100    4 OC.sub.4H.sub.9 0.70 5.31 0.12 >100    5 [00049] 1.17 11.13 0.15 >100    6 CH.sub.3 6.36 10.34 4.92  72.00 [00050] IC.sub.50 [μM] Compound Ar MEC1 U-2940 OCI-Ly7 M2-10B4 7 [00051] 7.16 24.72 1.01 >100    8 [00052] 0.20 2.50 0.50 >100    9 [00053] 1.10 9.49 0.13 >100    10 [00054] 1.90 7.37 1.48  17.05 11 [00055] >100 >100 >100 nt 12 [00056] 1.63 39.90 0.68 >100    13 [00057] 0.34 9.05 0.34  21.12 14 [00058] 0.17 0.86 0.10   8.20 15 [00059] 0.02 2.90 0.05  19.15 nt: not tested.

Comparison of the Ortho, Meta and Para Derivatives

[0191] The position of the ethoxy group which proved as biologically advantageous in the first optimization step was systemically varied. In particular, compounds 1 (as original lead), 14 and 15 (the two most active compounds arising from the optimization process) were chosen, and the corresponding congeners were synthesized and tested. The biological results thus obtained are indicated in Table 2 below. In all three sets the meta and para isomers were 10 to 100 fold less active than the ortho isomer. It can be clearly seen that para is being less preferred than meta which is very apparent in case of the sets of compound 1 and 15. The position of the ethoxy substituent thus plays an important role for the compounds' cytotoxic activity and ortho has been proved to be the most favored substituent position.

TABLE-US-00002 TABLE 2 Comparison of the biological activity of the ortho, meta and para derivatives of the three most active compounds on three malignant hematological cell lines (MEC1, U-2940 and OCI-Ly7). Position of the ethoxy IC.sub.50 [μM] Compound substituent Ar MEC1 U2940 OCI-Ly7  1 16 17 ortho meta para [00060] 0.06 2.85 nd  4.43 16.22 nd 0.06 1.76 nd 14 18 19 ortho meta para [00061] 0.17 2.21 7.50  0.86  7.59 14.59 0.10 1.67 4.77 15 20 21 ortho meta para [00062] 0.02 3.33 nd 2.90 nd nd  0.05  4.83 25.26 nd: no significant cytotoxic activity was detected up to 100 μM.

[0192] The cytotoxic activity of further heteroaromatic chalcone derivatives, including compounds of formula (I) according to the present invention as well as reference compounds, on the three malignant hematological cell lines MEC1, U-2940 and OCI-Ly7 is shown in the following Table 3:

TABLE-US-00003 TABLE 3 Cytotoxic activity of further heteroaromatic chalcone derivatives, i.e. compounds 22 to 35, on the malignant hematological cell lines MEC1, U-2940 and OCI-Ly7. IC50 [μM] Compound Structure MEC1 U-2940 OCI-Ly7 22 [00063] 0.05 1.71 0.03 23 [00064] 2.60 10.04 1.47 24 [00065] 26.57 49.98 15.92 25 [00066] 0.14 7.10 0.12 26 [00067] 0.04 10.14 0.08 27 [00068] 0.06 2.31 0.07 28 [00069] 5.48 12.89 4.78 29 [00070] 230.89 nd nd 30 [00071] 0.02 3.13 0.02 31 [00072] 0.20 7.10 0.05 32 [00073] 6.91 44.32 16.66 33 [00074] 38.79 42.17 19.49 34 [00075] 8.73 18.79 6.35 35 [00076] 34.32 56.20 19.04 nd: no significant cytotoxic activity was detected up to 100 μM.

[0193] Together, compound 15 developed by two lead optimization processes turned out to have the optimal structural requirements for potent inhibition of malignant hematological cell lines with less biological activity on normal mouse fibroblasts. Especially in conjunction with chalcone derivatives, the 3,4,5-trimethoxyphenyl moiety was previously described as an essential structural feature of potent cytotoxic compounds (Das U et al. Bioorg Med Chem 2009, 17, 3909-15; Dimmock J R et al. Bioorg Med Chem Lett 2005, 15, 1633-6; Romagnoli R et al. Bioorg Med Chem 2008, 16, 5367-76; Schobert R et al. J Med Chem 2009, 52, 241-6). Also in the case of other small molecules, for example 1,5-diaryl imidazole derivatives, this substitution pattern of the aromatic site proved to be most favored (Bellina F et al. Bioorg Med Chem Lett 2006, 16, 5757-62). In the context of the present invention, however, the 2-ethoxyphenyl moiety (as comprised in compounds 14 and 15) has been identified as a novel highly active structural principle in cytotoxic chalcone derivatives, including in particular the compounds of formula (I) according to the invention. Biological investigation of the homologous series of this structural feature proved the ethoxy substituent as most preferred. A recent study conducted by Maioral et al. investigating apoptosis induction of 1-naphthylchalcones in human acute leukemia cell lines described the derivative with a 2,5-dimethoxy substituent on the site of ring A as the most potent cytotoxic representative of the series tested with an IC.sub.50 value of 40.12 μM on K562 and 20.98 μM on Jurkat cells after 24 hours of incubation (Maioral M F et al. Biochimie 2013, 95(4), 866-74). Moreover, the compound showed to be non-toxic to peripheral blood lymphocytes with a cell viability of 99.89±10.69% at 50 μM compound concentration after 24 hours. These data can be seen in accordance with the results presented herein: the 1-naphthylchalcone with a 2-methoxy substituent on ring A proved to be the most potent one. However, through optimization of both ring A and ring B in the context of the present invention, an even more potent cytotoxic compound on hematological cell lines has been obtained.

Effect of Compound 15 on Other Hematological Cell Lines

[0194] Hematologic malignancies are highly heterogeneous in their biology and behavior. This and the fact that some patient groups are resistant to therapy underlines the urgent need for new therapeutic drugs. Compound 15 has therefore been tested on other cell lines representing a variety of hematologic neoplasms: two T-cell acute leukemia cell lines (CCRF, Jurkat), two myeloid leukemia cell lines (HL60, K562), and two additional B-cell lines (SU-DHL6, SU-DHL9). Viability was assessed as described in the methods section above. The results obtained in these tests are shown in FIG. 2. Compound 15 considerably reduced the viability of the hematologic cell lines to less than 30% of control already at concentrations<1 μM. An exception was the chronic myeloid leukemia line K562. Although viability was reduced down to 60% already at low concentrations, toxicity did not increase at increasing concentrations of compound 15 in this cell line (see FIG. 2). However, this cell line derives from a patient in blast crisis and is characterized by a number of genetic aberrations associated with aggressive disease and resistance to treatment (Drexler H G. K-562. In: The Leukemia-Lymphoma Cell Line FactsBook, Drexler H G (ed.), Academic Press: London, 2001; pp. 632-633). In all other cell lines, the biologic activity of compound 15 reached levels comparable to standard drugs used in therapy (Beesley A H et al. Brit J Cancer 2006, 95, 1537-1544; Tang R et al. BMC Cancer 2008, 8, 51; Lubgan D et al. Cell Mol Biol Lett 2009, 14, 113-127; Parker B W et al. Blood 1998, 91, 458-465; Dohse M et al. Drug Metab Dispos 2010, 38, 1371-1380; Weisberg E et al. Cancer Cell 2005, 7, 129-141; Czyzewski K et al. Neoplasma 2009, 56, 202-207). IC.sub.50 values for compound 15 are listed in Table 4.

TABLE-US-00004 TABLE 4 IC.sub.50 values (in μM) determined for compound 15 in different cell types. For comparison, the standard therapeutic drug fludarabine was tested in parallel in experiments using primary cells. CLL HD CLL CCRF Jurkat HL60 K562 SU-DHL6 SU-DHL9 Suspension Suspension Co-culture 15 0.03 0.04 0.02 nd 0.06 0.03 1.18 13.56 0.68 Fludarabine nd nd nd nd nd nd 1.85 13.87 10.22 CCRF, Jurkat: T-cell acute leukemia; HL60, K562: myeloid leukemia; SU-DHL6, SU-DHL9: B-cell lymphoma; CLL Suspension: primary CLL cells in suspension culture; HD Suspension: healthy donor cells in suspension culture; CLL co-culture: CLL cells in co-culture with M2-10B4 fibroblast cells; nd: no significant cytotoxic activity was detected up to 100 μM.
Comparison of Compound 15 with Fludarabine on MEC1, OCI-Ly7 and U2940

[0195] To put the efficacy of compound 15 into perspective, the inventors screened the cell lines of their screening panel also with fludarabine, i.e. [(2R,3R,4S,5R)-5-(6-amino-2-fluoro-purin-9-yl)-3,4-dihydroxy-oxolan-2-yl]methoxyphosphonic acid, which is a purine analog used in treatment regimens for a variety of indolent Non-Hodgkin lymphomas, for instance chronic lymphocytic leukemia (CLL). As shown in FIG. 3, compound 15 displayed much higher toxicity as compared to fludarabine in MEC1 and OCI-Ly cells and, furthermore, it had comparable efficacy in U-2940 cells. This is also reflected by the corresponding IC.sub.50 values which were 1-3 log smaller for compound 15 as compared to fludarabine (IC.sub.50 values were 0.02 μM and 42.34 μM (MEC1), 0.05 μM and 1.95 μM (U-2940), 2.90 μM and 105.50 μM (OCI-Ly7) for compound 15 and fluudarabine, respectively). Notably, while fludarabine had variable impact on viability in these 3 cell lines, the effect of compound 15 was more consistent. This not only reflects the biological and genetic differences involved, but also indicates a high therapeutic potential of compound 15 in antitumor regimens (Stacchini A et al. Leukemia Res 1999, 23, 127-136; Sambade C et al. Int J Cancer 2006, 118, 555-563; Chang H et al. Leukemia lymphoma 1995, 19, 165-171; Tweeddale M et al. Blood 1989, 74, 572-578).

Investigating the Effect of Compound 15 in Primary Cells

[0196] As a last step, it has been sought to evaluate the cytotoxicity of compound 15 in primary cells and compare its activity to the impact of fludarabine. To this end, peripheral blood mononuclear cells (PBMC) of chronic lymphocytic leukemia (CLL) patients were used in two experimental settings. They were cultured in conventional suspension culture being exposed to increasing concentrations of drug. However, CLL cells need close contact to the tumor microenvironment depending on and receiving survival signals from stromal cells which has impact on response to therapy. Therefore, as a second approach, CLL cells were cultured over a layer of mouse fibroblasts (M2-10B4) to include this biological aspect in drug evaluation. Such an approach is often used in pre-clinical assessment and testing of drugs in CLL cells (Kurtova A V et al. Blood 2009, 114, 4441-4450). Cells from healthy donors (HD) were included as control.

[0197] FIG. 4 shows the reduction of viability in the tested settings, and Table 4 (above) lists the IC.sub.50 values for both compound 15 and fludarabine in CLL and HD primary cells. Higher cytotoxicity of compound 15 was observed in PBMC from CLL as compared to HD in suspension culture (see FIGS. 4A and 4B). Also, in comparison, fludarabine had less effect in tumor cells and displayed a greater reduction of viability in healthy cells. This indicates a more favorable therapeutic ratio for compound 15. In co-culture, a protective effect for CLL cells usually is observed, also in the present experiments with fludarabine (see FIG. 4C). In contrast, when incubated with compound 15, CLL cells showed a similar reduction in viability as in suspension culture. Again, this indicates a high therapeutic potential of this novel compound.

Example 3: Combined Treatment of CLL Primary Cells with a Compound of Formula (I) and Further Anticancer Agents

[0198] To further explore the therapeutic potential of the compounds of formula (I) according to the present invention, compound 15 was tested in combination with three anticancer agents—i.e., ABT199, CAL101 (idealisib), or PCI32765 (ibrutinib)—which are currently tested in clinical studies for CLL and other B-cell malignancies. ABT199 is a BCL2 inhibitor, CAL101 a PI3Kδ inhibitor, and PCI32765 a BTK inhibitor. ABT199 is being used in various neoplasms where overexpression of BCL2 has been reported. Both CAL101 and PCI32765 target signaling pathways, PCI132765 the B-cell receptor pathway plus several other less defined kinases, CAL101 also the B-cell receptor pathway and in addition several other signaling pathways involving cytokines, hormones and other factors. Both drugs are tested in clinical studies in indolent B-cell malignancies.

[0199] Peripheral blood mononuclear cells (PBMCs) of CLL patients were incubated in increasing concentrations of one of the above-mentioned anticancer agents alone or increasing anticancer agent concentrations plus compound 15 in two different concentrations under standard conditions for 48 h before viability was determined (CellTiterBlue, Promega). Primary cells from 5 (ABT199) or 6 patients (CAL101, PCI32765) were included.

[0200] It was found that the addition of compound 15 to the different anticancer agents added to the cytotoxic effect of the respective anticancer agent alone, providing a synergistic effect, as also shown in FIGS. 5A to 5C. In all cases, higher concentrations of compound 15 also led to higher synergistic toxicities.

[0201] These results indicate that compound 15 enhances the cytotoxic effect of the tested anticancer agents ABT199, CAL101 and PCI32765. The compounds of formula (I), such as compound 15, are thus advantageous for combination treatments with a further anticancer agent (such as, e.g., ABT199, CAL101 or PCI32765), particularly for the therapy of chronic lymphoid leukemia (CLL). In addition, the compounds of formula (I) are also advantageous, e.g., as novel, single drug options for relapsed and/or refractory patients.