This invention relates to sulfonamides, their preparation, pharmaceutical compositions containing them and methods of using them in the treatment of tumors as radiosensitizers and chemosensitizers. Background:

The currently known radiosensitizers that are in clinical trials, such as nitroimidazoles, are hypoxic cell sensitizers and exert their radiation sensitizing effect only when given before the irradiation of tumors (G. E. Adams and I. J. Stratford, "Hypoxia-Dependent Radiation Sensitizers", Molecular Actions and Targets for Cancer Chemotherapeutic Agents, 1981, Page 401, Academic Press) . However, it is believed that the repair of radiation damage to DNA may be an important factor in the radiocurability of human tumors (K. K. Fu, "Biological Basis for the Internation of Chemotherapeutic Agents and Radiation Therapy", Cancer, May 1 Suppl., V. 55, 2123, 1985; S. Nakatsugawa and T. Sugahara, "Effects of Inhibitors of Radiation-Induced Potentially Lethal Damage Repair on Chemotherapy in

Murine Tumors", Int. J. Radiation Oncology Biol. Phys. V.8, 1555, 1982). Therefore, efforts in this field have recently been directed toward searching for agents that can sensitize tumors after radiation by interfering with the repair process. However, only a few agents have thus far been found to have such an effect. Agents which have been found to have this activity, such as lonidamine also have antitumor activity. It remains unclear as to whether the postradiation activity of compounds such as lonidamine, is only an additive effect

of cytotoxicity. (J. H. Kim et al., "Potentiation of Radiation Effects on Two Murine Tumors by Lonidamine", Hanr.p.r Research. 4ϋ, 1120, 1986) .

U.S. Patent 4,603,133 discloses amides and esters of 2-[N-(morpholinoalkyl)aminosulfonyl]-6-nitrobenzoic acids and compositions as useful adjuncts to radiation therapy.

These compounds have the formula:

wherein :

R! is hydroxy-(lower alkoxy), lower alkoxy, allyloxy, amino, monoalkylamino, dialkylamino, (hydroxyalkyl)amino, di(hydroxyalkyl)amino, or allylamino; R^ is hydrogen, lower alkyl from 1-4 carbon atoms, hydroxy-(lower alkyl), allyl; R3 is a morpholino radical of the formula 0 ⁽ CH2CH2)2N ⁽ CH2) _n ; and n is 2 or 3.

U.S. Patent 4,731,369 discloses amides and esters of 2-[N-(hydroxypiρeridinoalkyl) and

(hydroxypyrrolidinoalkyl)-aminosulfonyl]-6-nitrobenzoic acids as useful adjuncts to radiation therapy. These compounds have the formula:

wherein:

R ¹ is hydroxy-(lower alkoxy), lower alkoxy, allyloxy, amino, alkylamino, di(lower alkyl)-alkylamino, (hydroxyalkyl)amino, di(hydroxyalkyl)amino, or allylamino; R2 is hydrogen, lower alkyl from 1-4 carbon atoms, hydroxy-(lower alkyl), allyl; n is 2 or 3; m is 0, 1, or 2; and p is 1 or 2.

U.S. Patent 4,694,020 discloses amides and esters of 2-(substituted sulfamyl)-6-nitrobenzoic acids and pharmaceutical compositions useful for increasing the sensitivity of hypoxic tumor cells to therapeutic radiation. These compounds have the formula:

wherein:

R is hydroxy-(lower alkoxy), lower alkoxy, alkoxy- (lower alkoxy) , allyloxy, amino, monoalkylamino.

dialkyla ino, (hydroxyalkyl)amino, di(hydroxyalkyl)- amino, or allylamino; R2 and R-3 are each separately hydrogen, lower alkyl from 1-4 carbon atoms, hydroxy-(lower alkyl), allyl, amino-(lower alkyl), (lower alkyl)-amino-(lower alkyl), di(lower alkyl)-amino-(lower alkyl), (hydroxyalkyl)-amino(lower alkyl), (hydroxyalkyl)- alkylamino(lower alkyl), or di(hydroxyalkyl)- amino(lower alkyl) or when taken together along with the nitrogen to which they are attached represent a heterocyclic ring selected from morpholino, aziridinyl, azetidinyl, pyrrolidyl, piperidyl, or R ⁴ -substituted-3-oxopiperazin-l-yl wherein R ⁴ is hydrogen, lower alkyl from 1-4 carbon atoms, or hydroxyalkyl of from 2-4 carbon atoms.

Published European Patent Application 0270292 discloses 2-(substituted sulfamyl) derivatives of 4- nitrobenzamide as agents that increase the sensitivity of hypoxic cancer cells to x-rays and γ-radiation. These agents have the formula:

wherein: R! is hydrogen or loweralkyl of 1-4 carbons;

R^ and R ⁴ are the same or different and are each hydrogen, loweralkyl of 1-4 carbons, or hydroxyloweralky1;

R^ is loweralkyl of 1-4 carbons substituted with NQ!Q2 wherein Q ¹ is the same or different from Q^ and both Q ¹ and ζ - are hydrogen, loweralkyl of 1-4 carbons, or hydroxyloweralkyl, or Q^ and

Q2 taken together with the nitrogen atom in NQ^Q^ form a heterocyclic ring such as aziridinyl, azetidinyl, pyrrolidinyl, or piperidinyl. A broad class of sulfonamides have been described in the patent art and literature as pharmaceuticals and as agricultural agents. The closest ones are the following:

Published Japanese Patent Appln. 61/257,960 shows fungicidal sulfonamides of the formula:

where Z is CH or N; and Y is Cl, CF3 or CN. Published Japanese Patent Appln. 61/233660 shows a fungicidal sulfonamide of the formula:

Published Japanese Patent Appln. 61/200,958 shows antibacterial and fungicidal sulfonamides of the formula:

where X is H or Cl,

Summary of the Invention

Unlike many of the known radiation sensitizing agents, the compounds of the present invention are believed to exert their effect by inhibiting the repair of DNA strand breaks caused by radiation, thus the compounds are classified as postradiation sensitizers. This postradiation sensitizer terminology is descriptive of the mechanism of action of these compounds but should not be a temporal limitation for administration of the compounds. In order for the compounds to be effective they must be present after the radiation therapy.

Therefore they can be administered before, during or after the radiation therapy.

Further, since these compounds are believed to inhibit the repair of DNA strand breaks, they will be effective chemosensitizer agents when given in combination with chemotherapeutic agents which cause DNA strand breaks. For example the compounds of the present invention may enhance or sensitize the activity of intercalators, alkylating agents, DNA cross-linker agents and any other agents which exert their anticancer activity by interacting with DNA, causing strand breaks.

According to the present invention, there are provided compounds having the formula:

or a pharmaceutically acceptable salt thereof wherein: R ¹ , R ² , R ³ , R ⁴ and R ⁵ independently are H, alkyl, alkenyl, alkynyl of 1-10 carbon atoms, phenyl, substituted phenyl, F, Cl, Br, I, Nθ2, CN, CF3, (CH2) _m NR ⁶ R ⁷ (m=0-10) , CO2R ⁹ , OR ¹⁰ , COR ¹¹ , or

S(0) _n R ¹² (n=0-3), or R ¹ and R ² , R ² and R ³ , R ³ and R ⁴ , or R ⁴ and R^ when taken together may form -C0NHC0- or -CONMCO- wherein M is Na ⁺ , K ⁺ ' or Li ⁺ ;

R6 and R ⁷ independently are H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl, CF3 or R^ and R ⁷ taken together can form (CH2)pNR ⁸ (CH2)q (P and q independently are 2-6);

R8 and R ⁹ independently are H, alkyl, alkenyl, alkynyl or acyl of 1-10 carbon atoms; R ¹ ^ is H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl or substituted phenyl;

R ¹ is H, alkyl, alkenyl, alkynyl of 1-10 carbon atoms, phenyl, substituted phenyl or NR ¹³ R ¹⁴ ;

R ² is H, alkyl, alkenyl, alkynyl of 1-10 carbon atoms, phenyl, substituted phenyl or NR ¹ ^ ¹⁷

R ³ and R ¹⁴ independently are H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl or CF3, or R ¹³ and R ¹⁴ taken together can form (CH2)r R ¹ ^(CH2)s (r and s independently are 2-6);

R ¹ ^ is H, alkyl, alkenyl, alkynyl or acyl of 1-10 carbon atoms; R ¹ ^ and R ¹⁷ independently are H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl, CF3 or R ¹⁶ and R ¹⁷ taken together can form (CH2)tNR ¹⁸ (CH2)u (t and u independently are 2-6); R ¹⁸ is H, alkyl, alkenyl, alkynyl or acyl of 1-10 carbon atoms; Y is N or CR ⁵ ; _* each X independently is H, F, Cl, Br, I, NO2, CN, CF3, alkyl, alkenyl, alkynyl of 1-4 carbon atoms, phenyl, substituted phenyl, (CH2) _C NR ¹⁹ R ²⁰ (c is 0-10), CO2R ²² , OR ²³ , COR ²⁴ , or S(0)dR ²⁵ (d is 0-3); b is 1 or 2;

Z is N or CH;

R ¹⁹ and R ² ^ independently are H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl, CF3 or R ¹⁹ and R ²⁰ taken together can form (CH2)eNR ²¹ (CH2)f (e and f independently are 2-6) ; R ²¹ is H, alkyl, alkenyl, alkynyl or acyl of 1-10 carbon atoms; R ²² is H, alkyl, alkenyl or alkynyl of 1-10 carbon atoms;

R ²³ is H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl or substituted phenyl; R ²⁴ is H, alkyl, alkenyl, alkynyl of 1-10 carbon atoms, phenyl, substituted phenyl or NR ^R ²⁷ ; R ² ^ is H, alkyl, alkenyl, alkynyl of 1-10 carbon atoms, phenyl, substituted phenyl or NR ² R ^3u ; R ² > and ^' R ²⁷ independently are H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl, CF3 or R ^2έ > and R ²⁷ taken together can form (CH2)gNR ²⁸ .(CH2)h (9 and h independently are 2-6) ; R ²⁸ is H, alkyl, alkenyl, alkynyl or acyl of 1-10 carbon atoms; R ²⁹ and R ³ ^ independently are H, alkyl, alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl, CF3 or R ²⁹ and R ³ ^ taken together can form (CH2)jNR ³¹ (CH2)k (j and k independently are 2-6) ; R ³¹ is H, alkyl, alkenyl or alkynyl of 1-10 carbon atoms;

A is NR ³² or NR ³² QNR ³³ ;

Q is (CH2)w, (CH2) _x CO or (CH2) _X S0 ² ; w is 2-10; x is 0-10;

R ³² and R ³³ independently are H, Na ⁺ , K ⁺ , Li ⁺ , alkenyl, alkynyl, acyl of 1-10 carbon atoms, phenyl, substituted phenyl, benzyl or substituted benzyl; with the following provisos: (a) when X, R ¹ , R ³ and R ⁴ are H, R ² is H, methyl,

OH or Cl and Y is CH, then A cannot be NH; and (b) when X, R ¹ , R ² and R ⁴ are H, R ³ is OH and Y is CH, then A cannot be NH.

Also provided are pharmaceutical compositions containing compounds of Formula (I) .

Further provided are methods of treating a tumor in a mammal comprising administering to the mammal a compound of Formula (I) in combination with radiation and/or chemotherapy.

Additionally provided are processes for preparing the compounds of Formula (I), as more fully described hereinafter.

Preferred compounds of the present invention are those compounds of Formula (I) wherein: -SO2A is at the 1 or 2 position; and/or

Z is CH; and/or

X is 2-halogen, provided that when X is 2-halogen, -SO2A is at the 1 position.

Specifically preferred compounds of the present invention are:

(a) N- (3-Amidophenyl) -2-chloro-l-naphthalene- sulfonamide

(b) N- (3-Amidophenyl)-5-chloro-l- naphthalenesulfonamide

(c) N-(2-Amidophenyl)-4-chloro-l- naphthalenesulfonamide

(d) N- (3-Amidoρhenyl) -4-chloro-l- naphthalenesulfonamide

(e) N-(2-Amidoρhenyl)-2-chloro-l- naphthalenesulfonamide (f) Benzoic acid, 3-[ [ (4-chloro-l- naphthalenyl) sulfonyl]amino]-, ethyl ester (g) Benzoic acid, 3-[ [2-chloro-l- naphthalenyl) sulfonyl]amino] (h) N-[ (3-Dimethylamino)phenyl]-2-chloro-l- naphthalenesulfonamide

(i) N- (3-Acetylphenyl) -2-chloro-l- naphthalenesulfonamide (j) N-[3-(Aminosulfonyl)phenyl]-2-chloro-l- naphthalenesulfonamide (k) 3- [ (2-Chloro-l-naphthalenyl) sulfonylamino] -4- methoxybenzamide (1) N- (2,3-Dihydro-l, 3-dioxo-lH-isoindol-4-yl) -2- chloro-1-naphthalenesulfonamide (m) N- (3-Methylphenyl) -1-naphthalenesulfonamide (n) N-(3-Acetylphenyl)-l-naphthalenesulfonamide (o) N-(3-Hydroxyphenyl) -1-naphthalenesulfonamide (p) N-(4-Hydroxyphenyl) -1-naphthalenesulfonamide (q) N- (3-Chlorophenyl) -1-naphthalenesulfonamide (r) N-[3-(Aminosulfonyl)phenyl]-1- naphthalenesulfonamide

(s) N- (3-Iodophenyl) -1-naphthalenesulf onamide

(t) N- [3- (1-Methylethoxy) phenyl] -1- naphthalenesulf onamide (u) N- [3- (1, 1-Dimethyl) phenyl ] -1- naphthalenesulfonamide

(v) N- [3-Aminosulf onyl) phenyl] -2-chloro-l- naphthalenesulf onamide, or the sodium salt thereof

(w) 3- [ (2-Chloro-l-naphthalenyl) sulfonylamino] - benzamide, or the sodium salt thereof

(x) 3-[ (2-Chloro-l-naphthalenyl)sulfonylamino]- benzamide, or the sodium salt thereof (y) 3-[(2-Chloro-l-naphthalenyl)sulfonylamino]- benzoic acid, or the sodium salt thereof (z) N-(4-Acetylρhenyl)-2-chloro-l- naphthalenesulfonamide (aa) N-(4-Hydroxyphenyl)-2-chloro-l- naphthalenesulfonamide (bb) N-(4-Chlorophenyl)-2-chloro-l- naphthalenesulfonamide

(cc) N-[4-Aminosulfonyl)phenyl]-2-chloro-l- naphthalenesulfonamide (dd) 3-[ (4-Chloro-l-naphthalenyl)sulfonylamino] benzamide, or the sodium salt thereof (ee) 3-[(5-Chloro-l-naphthalenyl)sulfonylamino] benzamide, or the sodium salt thereof (ff) 3-[(2-Chloro-l-naphthalenyl)sulfonylaminio]-N-

[2-(dimethylamino) ]ethyl benzamide (gg) 3[[6-[(2-Chloro-l-naphthalenyl)sulfonylamino]- 1-oxohexyl]amino] benzamide

(hh) N- (3-Amidophenyl) -2-naphthalenesulf onamide

(ii) 3- [ (8-Quinolinylsulfonyl) amino] benzamide .

Detailed Description of the Invention Chemistry

The compounds of the present invention can be prepared according to Scheme I. The compounds of Formula (I) can be prepared by the reaction of the sulfonyl chlorides of Formula (2) with the amines of Formula (3) in a suitable solvent such as pyridine, acetone or methylene chloride, with or without the addition of a suitable base, at a temperature from room temperature to the reflux temperature of the solvent. Alternatively, the compounds of Formula (I) can be prepared by the simultaneous addition of a solution of

an amine of Formula (3) in a suitable solvent, such as tetrahydrofuran (THF) , and a solution of a suitable base, such as potassium carbonate, in a suitable solvent, such as water, to a solution of an appropriate sulfonyl chloride of Formula (2) in a suitable solvent, such as THF at a temperature from room temperature to the reflux temperature of the solvent. The reaction of a sulfonyl chloride with an amine to produce a sulfonamide is well-known in the literature. The products of these reactions may be purified by techniques well-known to those skilled in the art of organic synthesis, including but not limited to recrystallization, trituration, chromatography, and/or acid base extraction procedures. Preparation of pharmaceutically acceptable salts of the compounds of Formula (I) can be in accordance with well-known techniques of forming salts. Physiologically acceptable salts include but are not limited to acid addition salts such as hydrochloric, sulfuric, acetic, succinic, citric, and benzene sulfonic acid salts of the compounds of Formula (I) which contain one or more basic functional groups, and the lithium, sodium or potassium salts which may be derived by the addition of a suitable base such as a metal hydroxide or metal hydride.

Materials of increased water solubility can be prepared by the addition of one or two equivalents of an aqueous sodium hydroxide solution to a suspension of a sulfonamide of the present invention in an appropriate solvent such as water, methanol or ethanol, followed by evaporation to dryness. When a compound which contains only one highly acidic proton is treated with two equivalents of sodium hydroxide, a compound with the emperical formula of a disodium salt is produced.

Scheme I

solvent

The compounds of this invention and their preparation can be better understood by the following examples, which do not constitute a limitation of the invention.

Example 1 N-(3-Amidophenyl )-2-chloro-l-naphthalenesulfonamide To a solution of 3-aminobenzamide (6 g, 50 mmole) in THF (150 ml) was added dropwise simultaneously a solution of 2-chloro-l-naphthalenesulfonyl chloride (13 g, 50 mmole) in THF (100 ml) and a solution of K2CO3

(6.9 g, 50 mmole) in water (50 ml) at 0°C over a period of 1 hour. The reaction mixture was stirred for 20 hrs at 25°C and the organic layer was separated and dried over Na2Sθ4. After the evaporation of solvent, the residual oil was purified by flash chromatography on silica gel with methylene chloride/methanol (19/1) as

the eluent to give the title product (7.9 g, 43%), mp 202-205°C.

The title compound was also prepared by adding dropwise for 30 minutes, a solution of 2-chloro- naphthalenesulfonyl chloride (9.7 g, 37 mmole) in acetonitrile (30 ml) into a mixture of 3-aminobenzamide (4.8 g, 35 mmole) and 3-dimethylaminopyridine (0.78 g, 6.5 mmole) in pyridine (40 ml) at 25°C under nitrogen. Then the reaction mixture was stirred at 25°C for 30 minutes and water (250 ml) was added dropwise and then poured into another 250 ml of water. The resultant suspension was filtered, and the solid was washed with water and dried in vacuo to give the crude product (11.8 g) as a red solid. Recrystallization of various batches of crude product so made with hot methanol afforded the title compound in about 70% yield as a white solid.

Example 2

N- 3-Ατnidophenyl)-5-chloro-l-naph ha1enesulfonamide A solution of 3-aminobenzamide (5.5 g, 40 mmole) in acetone (75 ml) was added dropwise at 25°C into a solution of 5-chloro-l-naphthalene sulfonyl chloride (10 g, 40 mmole) in acetone (50 ml) over a period of 45 min. The reaction mixture was stirred for 20 hours and filtered to give a yellowish solid which was washed in sequence with acetone (25 ml) , water (25 ml) , and hot methanol (25 ml), and yielded the title compound (5.7 g, 40%) after drying in vacuo at 50°C for 2 hours, m.p. 257-259°C.

Example N-(2-Amidophenvl)-4-ch1oro-1-naphthalenesulfonamide

A solution of 4-chloronaphthalenesulfonyl chloride (5.00 g, 19.15 mmole) and anthranilamide (2.61 g, 19.17 mmole) in pyridine (25 ml) was heated at reflux for 3

hours, cooled to 25°C, and concentrated in vacuo. The tan pasty residue was triturated repeatedly with hot methanol to afford the title compound (5.07 g, 73%) as an off-white powder, m.p. 238-239°C. The compounds of this invention which were prepared or can be prepared according to the above procedures are listed in Tables I, II and III.

Ex. X si R ² . R ³ 1 Y A mp (°C)

1 2-C1 H CONH2 H H CH NH 202-205

2 5-C1 H CONH2 H H CH NH 257-259

3 4-Cl CONH2 H H H CH NH 238-239

4 H H CONH2 H H CH NH 182-185

5 3-C1 H CONH2 H H CH NH

6 4-Cl H CONH2 H H CH NH 185-190

7 6-C1 H CONH2 H H CH NH

8 7-C1 H CONH2 H H CH NH

9 H CONH2 H H H CH NH 255-256

10 2-C1 CONH2 H H H CH NH 235-239

11 5-C1 CONH2 H H H CH NH

12 H H H CONH2 H CH NH

13 2-C1 H H CONH2 H CH NH 267-271

14 4-Cl H H CONH2 H CH NH >355

15 5-C1 H H CONH2 H CH NH

16 2-C1 H H H H CH NH 134-137

17 4-Cl H H H H CH NH

18 5-C1 H H H H CH NH 149-153

19 H H CN H H CH NH

20 2-C1 H CN H H CH NH

21 4-Cl H CN H H CH NH 209-210

22 5-C1 H CN H H CH NH

23 H H C02Et H H CH NH

24 2-C1 H C02Et H H CH NH 116-119

25 4-Cl H C02Et H H CH NH 110-111

26 5-C1 H C02Et H H CH NH

Table I (continued)

ix. X *i Si 1 El Y A mp (°C)

27 H H CF3 H H CH NH

28 2-C1 H CF3 H H CH NH

29 4-Cl H CF3 H H CH NH 154-159

30 5-C1 H CF3 H H CH NH

31 2-C1 N02 H H H CH NH

32 2-C1 H N02 H H CH NH 177.5-179

33 2-C1 H H N02 H CH NH

34 2-C1 H C02H H H CH NH 221-226

35 2-C1 H C02Me H H CH NH

36 2-C1 H NH2 H H CH NH 191-193

37 2-C1 H N β2 H H CH NH 186-188

38 2-C1 H CONHMe H H CH NH

39 2-C1 H C0NMΘ2 H H CH NH

40 2-C1 H OH H H CH NH 181-182

41 2-C1 H OMe H H CH NH

42 2-C1 H C6H5 H H CH NH 173-175

43 3,7-di-nBu H OMe OMe OMei CH NH

44 4,5-di-OH H CONH2 H H CH NH

45 3-OH4NH2 H CONH2 H H CH NH

46 2-C1 H ^' COMe H H CH NH 134-136

47 2-C1 H Me H H CH NH 187-188

48 2-C1 H OEt H H CH NH

49 2-C1 H SO2NH2 H H CH NH 281-286

50 2-C1 H Cl H H CH NH 180-182

51 2-C1 H I H H CH NH 207-209.5

52 4-Br H CONH2 H H CH NH

53 4-1 H CONH2 H H CH NH

54 4-N02 H CONH2 H H CH NH

55 4-CN H CONH2 H H CH NH

56 4-Me H CONH2 H H CH NH

57 2-Pr H CONH2 H H CH NH

58 2-CF3 H CONH2 H H CH NH

Table I (cont inued)

Ex. X si Si S si Y A mp (°C)

59 2-C6H5 H CONH2 H H CH NH

60 2-Br H NMe2 H H CH NH

61 5-NMe2 H NMe2 H H CH NH

62 5-C1 H Me2 H H CH NH

63 4-NH2 H CONH2 H H CH NH

64 4-NHMe H CONH2 H H CH NH

65 4-NMe2 H CONH2 H H CH Nri

66 4-C02H H CONH2 H H CH NH

67 4-C02Me H CONH2 H H CH NH

68 4-CONH2 H CONH2 H H CH NH

69 4-OH H CONH2 H H CH NH

70 -OMe H CONH2 H H CH NH

71 4-COMe H CONH2 H H CH NH

72 4-SH H CONH2 H H CH NH

73 4-SMe H CONH2 H H CH . NH

74 4-SOMe H CONH2 H H CH NH

75 4-S02Me H CONH2 H H CH NH

76 H H CONH2 H H N NH

77 2-C1 H CONH2 H H N NH

78 4-Cl H CONH2 H H N NH

79 5-OH H CONH2 H H N NH

80 6-NH2 H CONH2 H H N NH

81 4-OMe H CONH2 H H N NH

82 5-NMe2 H CONH2 H H N NH

83 6-NO2 H CONH2 H H N NH

84 H Me CONH2 H H CH NH

85 2-C1 H CONH2 H Me CH NH

86 2-C1 H CONH2 H H CHMe NH 237-240

87 5-C1 H CONH2 Me H CH NH

88 H H CONH2 H OMe CH NH

89 2-C1 H CONH2 H H CHOMe NH 208-210

90 4-Cl H CONH2 OMe H CH NH

Table I (cont inued)

Ex. X Si Si i si Y A rnp (°C)

91 5-C1 OMe CONH2 H H CH NH

92 2-C1 H CONH2 H H CH NH(CH2)2NH

93 2-C1 H CONH2 H H CH NH(CH2)3NH

94 2-C1 H CONH2 H H CH NH(CH2)4NH

95 2-C1 -CONHCO- H H CH NH 221-227

96 2-C1 H -CONNaCO- H H CH NNa >275

97 2-C1 H CONH2 H H CH NH(CH2)lθNH

98 3,6-di-tBu H CONH2 H H CH NH

99 H H H H H CH NH 157-158

100 H H Me H H CH NH 133

101 H H COMe H H CH NH 163-164

102 H H OH H H CH NH 142-144

103 H H H OH H CH NH 192-194

104 H H Cl H H CH NH 136-137

105 H H NMe2 H H CH NH 159-160

106 H H C6H5 H H CH NH 189-191.5

107 H H SO2 H2 H H CH NH 209-212

108 H H I H H CH NH 146-147

109 H H OiPr H H CH NH 135-149

110 H H tBu H H CH NH 158-160

111 2-C1 H OiPr H H CH NH 134-137

112 2-C1 H tBu H H CH NH 169-172

113 2-C1 H S02NHNa H H CH NNa >300

114 2-C1 H CONH ₂ »NaOH H H CH NNa >300*

115 2-C1 H CONH2 H H CH NNa >300

116 2-C1 H C02Na H H CH NNa >300

117 4-NHAc H H Me H CH NH

118 2-C1 H H COMe H CH NH 253-255

119 2-C1 H H OH H CH NH 180-182

120 2-C1 H H Cl H CH NH 164-166

122 2-Br H H Mβ2 H CH NNa

Table I ( con i nuprn

Ex. X R^ si si Y A mp (°C) 123 2-Cl H H SO2 H2 H CH NH 251-254 124 2-Cl H H I H CH NH 183-185. 125 4-NHAc H H tBu H CH NH 126 4-Cl CONH ₂ ^» NaOH H H H CH NNa 287-288* 127 4-Cl H CONH ₂ ^« NaOH H H CH NNa >300* 128 4-Cl H H CONH ₂ ' NaOH H CH NNa >300* 129 4-Cl NH2 H H H CH NH 172-178 130 4-Cl C02H H H H CH NH 131 4-Cl H H NH2 H CH NH >300 132 5-C1 H CONH ₂ ^« NaOH H H CH NNa >300* 133 5-NMe2 H H H H CH NH 128-131 134 2-Cl H CON- H H CH NH 145-182

(CH2CH2 ) 2NMe

135 2-Cl H CH2N- H H CH NH

(CH2CH2) 2NMe

136 2-Cl CONH- H CH NH 231-233

CH2CH2NMe2

137 2-Cl CH2NH- H H CH NH

CH2CH2NMe2

138 2-Cl CONH2 H H CH NH ⁽ CH2 ⁾ 6~ 109-114 CONH

139 2-Cl H H CO2H H N NH 259-261 140 H OMe H OMe H CH NH 134-136 141 2-Cl OMe H OMe H CH NH 106-108 140 H OMe H H OMe CH NH 138-140 141 2-Cl OMe H H OMe CH NH 143-144 142 H H OMe OMe OMe CH NH 138-139 143 2-Cl H OMe OMe OMe CH NH 144-145 144 2-Cl H CONH2 H H CH NNa >300 145 H H H H H CH NH 152-153 146 2-Cl H OMe H H CH NH 147 2-Br C10H21 H H CH NH

Table I (continued)

Ex. X Si Si Si si Y A mp (°C)

148 8-C1 H ⁽ CH2 ⁾ 8- H H CH NH CHCH2

149 7-NH2 H H (CH2)8CCH H CH NH

150 5-NMe2 H H H C ₆ H ₅ CH NH

151 2-Cl H H P-C6H4NO2 H CH NH

152 5-NMe2 H C02Me H H CH NH

153 5-NMe2 H CO2C10H21 H H CH NH

154 2-Cl H C02COMe H H CH NH

155 2-Cl H 02CMe H H CH NH

156 2-Cl H O2CC10H21 H H CH NH

157 2-Cl H ⁽ CH2 ⁾ 5NMe2 H H CH NH

158 2-Cl H SO3H H H CH NH

159 4-Cl H S02Me H H CH NH

160 5-C1 ^' H H SOMe H CH NH

161 2-Cl H SMe H H CH NH

162 4-NH25- ^■ OH H SMe H H CH NH

163 HC6H5 H H SMe H CH NH

164 2-Cl H H ⁽ CH ₂ ⁾ 5- H CH NLi NMeCOMe

165 2-Br H CO2K H H N NK

166 5-NMe2 H C02Me H H N NH

167 2-Cl H CONH2 H H CH NHCONH

168 6-NO2 H H H H CH NHCH2CONH

169 5-OH H H H H CH NH(CH2)5S02NH

170 4-NHAc OMe OMe H H CH NH(CH2)6NH

Compounds which are listed in Table I as disodium salts were prepared by the addition of two equivalents of sodium hydroxide to the parent compound as explained in the detailed description of the invention

Ex. X Si Si si sl Y A mp (°C)

171 H H C0NH2 H H CH NH 218-221

172 5- •Cl H H H H CH NH 180-183

173 5- ^■ Cl H C0NH2 H H CH NH 206-208

174 H C0NH2 H H H CH NH

175 H H H CONH2 H CH NH

176 H H H H H CH NH

111 H H Me H H CH NH

178 H H COCH3 H H CH NH

179 H H OH H H CH NH

180 H H Cl H H CH NH

183 H H SO2NH2 H H CH NH

184 H H I H H CH NH

185 H H OiPr H H CH NH

186 H H tBu H H CH NH

187 H H OMe H H CH NH

188 H H OMe OMe OMe CH NH

189 H H OMe H OMe CH NH

190 H H CF3 H H CH NH

191 H H NO2 H H CH NH

192 5- •Cl H Me H H CH NH

193 5- •Cl H COMe H H CH NH

194 5- ^■ Cl H OH H H CH NH

195 5- ^■ Cl H Cl H H CH NH

196 5- ^■ Cl H NMe2 H H CH NH

197 5- ^■ Cl H NMe2 H H CH NNa

198 5- •Cl H SO2NH H H CH NH

Table II (continued)

Ex. X Si Si Si si Y A mp (°C)

199 5-Cl H 1 H H CH NH

200 5-Cl H OiPr H H CH NH

201 5-Cl H tBu H H CH NH

202 5-Cl H OMe H H CH NH

203 5-Cl H OMe OMe OMe CH NH

204 5-Cl H OMe H OMe CH NH

205 5-Cl H CF3 H H CH NH

206 5-Cl H NO2 H H CH NH

207 5-Cl C10H21 H H H CH NH

208 5-Cl H (CH ₂ )8- H H CH NH CHCH2

209 5-Cl H H (CH2)8CCH H CH NH

210 5-Cl H H H C6H5 CH NH

211 5-Cl H H P-C6H4NO2 H CH NH

212 5-Cl ^' H C02Me H H CH NH

213 5-Cl H CO2C10H21 H H CH NH

214 5-Cl H C02COMe H H CH NH

215 5-Cl H 02CMe H H CH NH

216 5-Cl H O2CC10H21 H H CH NH

217 5-Cl H (CH2)5NMe2 H H CH NH

218 5-Cl H SO3H H H CH NH

219 5-Cl H S02Me H H CH NH

220 5-Cl H H SOMe H CH NH

221 H H SMe H H CH NH

222 H H SMe H H CH NH

223 H H H SMe H CH NH

224 H H H (CH2)5NMeCOMe H CH NLi

225 H H C02K H H N NK

226 H H C02Me H H N NH

227 H H CONH2 H H CH NHCONH

228 H H H H H CH NHCH2CONH

229 H H H H H CH NH(CH ₂ <)5SO2NH

230 H OMe OMe OMe H CH NLi

Ex. R£ si A mp (°C)

231 H H H H CH NH

232 CONH2 H H H CH NH

233 H CONH2 H H CH NH 205-207

234 H H CONH2 H CH NH

235 H H H H CH NH

236 H Me H H CH NH

237 H COMe H H CH NH

238 H OH H H CH NH

239 H Cl H H CH NH

240 H NMe2 H H CH NH

241 H NMe2 H H CH NNa

242 H SO2NH2 H H CH NH

243 H I H H CH NH

244 H OiPr H H CH NH

245 H tBu H H CH NH

246 H OMe H H CH NH

247 H OMe OMe OMe CH NH

248 H OMe H OMe CH NH

249 H CF3 H H CH NH

250 H NO2 H H CH NH

251 H H (CH2)8CCH H CH NH

252 H H H C6H5 CH NH

253 H CO2C10H21 H H CH NH

254 H C02COMe H H CH NH

255 H 02CMe H H CH NH

256 H O2CC10H21 H H CH NH

257 H (CH2)5NMe2 H H CH NH

Table III (continued)

Ex . R ¹ Si Si i Y A mp (°C )

258 H S03H H H CH NH

259 H S02Me H H CH NH

260 H H SOMe H CH NH

261 H SMe H H CH NH

262 H SMe H H CH NH

263 H H SMe H CH NH

264 H H (CH2 ) 5NMeCOMe H CH NLi

265 H CO2K H H N NK

266 H C02Me H H N NH

267 H C0NH2 H H CH NHCONH

268 H H H H CH NHCH2CONH

269 H H H H CH NH (CH2 ) 5S02NH

270 OMe OMe OMe H CH NLi

RADIOB IOLOGTCAL ASSAYS

Tumor Cell Survival Assay f in Vivo - In Vitro Assay)

For this assay, EMT6 tumors in female BALB/c mice are used. These mice are bred in the Stanford Radiobiology colony under specific pathogen-free conditions and are 3 to 4 months old at the beginning of each experiment. The EMT6 tumor is grown intradermally in the flank from an inoculation of 2x10^ tumor cells taken from the 2nd to 8th in vitro passage of tumor cells since removed from a previous tumor in BALB/c mice. Two tumors per mouse are implanted. These are used at a volume of approximately 100 mm ³ . At this point, the tumors contain approximately 20% hypoxic cells.

The first in vivo radiosensitization experiment is done with a fixed dose of intraperitoneally (ip) injected drug (usually 2 mmole/kg or 2/3 LD50, whichever is lower) , a fixed radiation dose (20 Gy) , and a

variable interval between irradiation and injection, or between injection and irradiation. If tumor drug concentrations are required, one of the two tumors in each mouse is cut in half, and one half is immediately frozen for subsequent analysis of drug levels by high pressure liquid chromatography (HPLC) .

Irradiation of the EMT6 tumors is done by irradiating nonanesthetized, tumor-bearing mice in a Plexiglas® box. Irradiation conditions are low LET 250- kVp X-rays, 15 mA, FSD 33 cm, added filtration of 0.35 mm Cu, half value layer 1.3 mm Cu, and a dose rate of 130 rad/min.

To assay for cell survival, the tumor-bearing mice are killed immediately after irradiation. The tumors are dissected from the skin, cut into several pieces, and made into a fine brei by high-speed chopping with a razor blade attached to a jigsaw. The brei is then added to 30 ml of Hank's Balanced Salt Solution (HBSS) containing the following enzyme concentrations: 0.02% DNase, 0.05% pronase, and 0.02% collagenase. The suspension is stirred for 30 min at 37°C and centrifuged. The cell pellet is resuspended in complete Waymouth's medium plus 15% Fetal Calf Serum (FCS) , and an aliquot is mixed with trypan blue and the cells are counted with the use of a hemacytometer. Suitable dilutions of this single-cell suspension are then made in complete Waymouth's medium plus serum and plated into 60- or 100-mm polystyrene Petri dishes (Lux Scientific Corp.) in 5 or 15 ml of medium. After incubation for 13 days, the colonies are fixed and stained, and those containing 50 cells or more are counted. The dilution yielding an average count of 25 to 100 colonies in a 60- mm dish is used in the calculation of results. Results are determined as the ratio of cells killed with

radiation versus cells killed with radiation plus sensitizer (Table IV) .

Table IV Tumor Cell Survival Assay Results ¹

Example Dose ( g/kq) SER ²

1 400 1.80

2 400 1.25 6 400 1.55

16 400 1.19

¹ EMt 6 tumors in mice were treated with 20 Gy.

* ² Sensitizer Enhancement Ratio (SER) is the ratio of the plate efficiency of cells taken from tumors treated with radiation and drug versus tumors from animals treated with radiation alone. An SER of >1.0 is considered active.

Regrowth Delay Assay

This assay is performed with the SCCVII carcinoma transplanted in C3H mice. It is an excellent tumor for regrowth delay studies because it has a low spontaneous metastasis rate, it is relatively nonimmunogenic in its syngeneic host, and grows to a large volume without compromising the health of its host.

For tumor inoculation, cells are taken from the 2nd to the 5th in vitro passage of a SCCVII tumor previously removed from a C3H mouse. Between 1 and 2x10^ cells are inoculated in a volume of 0.05 ml HBSS intradermally in the dorsum approximately 1 cm proximal to the base of the tail.

The assays for each test sensitizer result in two growth delay curves (one for vehicle controls and one for the test drug) , in which the mean number of days delay for the tumor to reach 4X its volume at the time of radiation is plotted as function of time. The test sensitizer was given at a dose selected in the tumor cell survival assay experiment and at its optimal time interval (also determined in the tumor cell survival assay) . Mice are irradiated in a specially designed lead shield, with only the tumor and lower part of the dorsum exposed. The mice are retained by taping the tail to the side of the shield. Four mice are irradiated simultaneously with 250-KVp X-rays, FSD 31 cm, dose rate of 167 rad/min. Each growth delay curve is produced from five groups (four radiation doses + unirradiated control) of 6 mice each. Radiation dose used was 20 Gy.

Tumor diameter is measured daily in three dimensions with a vernier caliper and tumor volume calculated. At treatment tumors were about 300 mm ³ to 500 mm ³ . After treatment tumors were measured three times per week until each tumor reaches four-fold its initial volume. The mean number of days after treatment for tumors in each group to reach four times their treatment volume is calculated. This growth delay to four times initial tumor volume which is the difference between the mean in irradiated and unirradiated controls, or between irradiated pulse drug versus unirradiated control, is shown in Table V.

Table V

Tumor Regrowth Delay Results ¹ Example Growth Delay (day)

Radiation alone 14.2

Ex. 1 + radiation 30.0

¹ SCC-VII tumors in mice were treated with 20 Gy.

Clonogenic Survival Assay

Human colon cancer clone A cells (1 x 106) were plated in 60-mm tissue culture dishes in RPMI-C medium on day 0. The cells were incubated in a humidified atmosphere of 5%Cθ2~95% air at 37°C for 24 hrs. The culture ^" medium was then removed and replaced with 4 ml of fresh RPMI-C medium. The cells were irradiated with or without 5.7 Gy of radiation. Test analogs (1 ml, 5X concentration) were added to two similar plates (+/- radiation) immediately after radiation. The cultures were incubated at 37°C for 2 hrs and then the cells were harvested with trypsin (0.033%) and centrifuged. The cells were resuspended in RPMI-C and the cell concentrations were adjusted for appropriate seeding density (depending on concentrations of testing analogs and whether the cells were treated with radiation) . After seeding, cultures were maintained for 10 days and then the cells were washed with 0.9% NaCl and stained with crystal violet (0.5% in absolute alcohol) and the number of colonies with more than 50 cells/colony were counted. The plating efficiency (PE) was defined as the percentage of colonies formed from the total number of cells seeded. The radiosensitizing effect was defined by the survival ratio (SR) calculated from the following equation.

PE (rad) PE (analog) SR = x

PE (rad+analog) PE control

where

PE (rad) = plating efficiency of cells treated with radiation alone PE (rad+analog) = plating efficiency of cells treated with radiation and test analog

PE (analog) = plating efficiency of cells treated with test analog alone PE (control) = plating efficiency of control (no treatment) cells Any test analog with a SR > 1.5 is considered positive in this- clonogenic survival assay. Data are shown in Table VI.

Inhibition of Repair of DNA Double? Strand Breaks Induced by Radiation

L1210 Cells (3 x 10 ⁵ cells/ml) were incubated with 0.02 μCi/ l of [2- ¹⁴ C]thymidine (sp. act. 54.0 Ci/mmol) in a humidified atmosphere of 5% Cθ2~95% air at 37°C for 24 hrs. The cells were then harvested and centrifuged. The cells were resuspended and adjusted to a concentration of 1 x 106 cells/ml. The cells were irradiated on ice for 1 hour in a Gamma cell 40 irradiator at a flux rate of 1.14 Gy/min. The cell suspensions were then incubated with or without test analogs for 2 hr at 37°C. The DNA double-strand breaks in each sample were measured by neutral elution procedures (Kohn "X-ray Induced DNA Double Strand Break Production and Repair in Mammalian Cells as Measured by Neutral Filter Elution, " Nucleic Acids Research, 2, p. 793-804 (1979)). The cells were diluted with cold

phosphate buffered saline (PBS) and loaded onto a Smokestack funnel fitted with a 2 μ polycarbonate filter. After washing the cells three times with cold PBS, the cells were lysed with 5 ml of SDS-EDTA lysis solution. After draining the lysis solution into scintillation vials, the cell lysates were deproteinized with SDS-EDTA lysis solution containing 0.5 mg/ml proteinase K. The DNA retained on the filter was eluted with 30 ml of 0.02 M tetrapropyl ammonium hydroxide - EDTA solution (pH = 9.6) at a flow rate of 0.035 ml/min. The amount of radioactive DNA retained on the filter after 10 hr elution was determined. The inhibition of DNA repair by test analog is calculated by the following formula:

DNA _a -DNA ₀

% Inhibition = 100 - { ( ) x 100]

DNAb-DNAo

where

DNA _a is %DNA retained when cells were incubated at

37°C in the presence of test analog DNA _f c is %DNA retained when cells were incubated at

37°C in the absence of test analog (designated as 100% repair)

DNA _© is %DNA retained when cells remained on ice for 2 hrs after irradiating with 68.4 Gy of radiation (designated as 0% repair) If a testing analog produced a >50% inhibition of DNA repair, the analog was considered active and a "+" sign was assigned in Table VI.

Table VI

Aerobic Cell Inhibition of DNA

Ex. Sensitization ¹ ' ³ Double Strand Break Repair ² ' ³

1 + +

2 - +

3 - +

6 + +

10 + nt

13 - +

16 - +

24 - nt

25 + +

29 - +

32 - +

34 + nt

36 + nt

37 + -

40 - +

42 - nt

46 + +

47 - +

49 + nt

50 - +

51 - +

86 - +

89 + nt

95 + +

99 - +

100 + +

101 + nt

102 + +

103 + +

Table VT f mn n^ ) Aerobic Cell Inhibition of DNA

Ex. £iensiti ion ¹ ' ³ Double Strand Break Repair ² ' ³

104 + +

106 - +

107 + nt

108 + +

109 + +

110 + +

111 - +

112 - +

113 + nt

114 + +

115 + nt

116 + nt

118 + nt

119 + +

120 + +

123 + nt

124 - +

126 - nt

127 + nt

128 - +

129 - +

132 + +

133 - +

134 - +

136 + +

138 + nt

171 + nt

172 - +

173 - +

233 + nt

Table VI (continued)

1) In this test, compounds with a SR of >1.5 are "+" and compounds with a SR of <1.5 are "-".

2) In this test, compounds which inhibit DNA double strand break repair >50% are "+" and compounds which inhibit DNA double strand break repair <50% are "-".

3) The "nt" indicates that the test was not performed on this compound.

Dosage Forms

The postradiation and/or chemotherapeutic sensitizing compounds (active ingredients) of this invention can be administered to enhance radiation or chemotherapy treatment by any means that produces contact of the active ingredient with the agent's site of action in the body of a mammal after such radiation or chemotherapy treatment. They can be administered by any conventional means available for use in conjunction with pharmaceuticals; either as individual active ingredients or in a combination of active ingredients. They can be administered alone, but are generally administered with a pharmaceutical carrier selected on the basis of the chosen route of administration and standard pharmaceutical practice. The dosage administered will be a radiation or chemotherapy enhancing amount of active ingredient and will, of course, vary depending upon known factors such as the pharmacodynamic characteristics of the particular active ingredient, and its mode and route of administration; age, health, and weight of the recipient; nature and extent of symptoms, kind of concurrent treatment, frequency of treatment, and the effect desired. Usually a dosage of active ingredient can be about 5 to 1000 milligrams per kilogram of body

weight administered after radiation. A typical dose is about 400 mg/kg.

Dosage forms (compositions) suitable for internal administration contain from about 5 milligrams to about 1000 milligrams of active ingredient per unit. In these pharmaceutical compositions the active ingredient will ordinarily be present in an amount of about 0.5-95% by weight based on the total weight of the composition.

The active ingredient can be administered orally in solid dosage forms, such as capsules, tablets, and powders, or in liquid dosage forms, such as elixirs, syrups, and suspensions, it can also be administered parenterally, in sterile liquid dosage forms.

Gelatin capsules contain the active ingredient and powdered carriers, such as lactose, sucrose, mannitol, starch, cellulose derivatives, magnesium stearate, stearic acid, and the like. Similar diluents can be used to make compressed tablets. Both tablets and capsules can be manufactured as sustained release products to provide for continuous release of medication over a period of hours. Compressed tablets can be sugar coated or film coated to mask any unpleasant taste and protect the tablet from the atmosphere, or enteric coated for selective disintegration in the gastrointestinal tract.

Liquid dosage forms for oral administration can contain coloring and flavoring to increase patient acceptance.

In general, water, a suitable oil, saline, aqueous dextrose (glucose), and related sugar solutions and glycols such as propylene glycol or polyethylene, glycols are suitable carriers for parenteral solutions. Solutions for parenteral administration contain preferably a water soluble salt of the active ingredient, suitable stabilizing agents, and if

necessary, buffer substances. Antioxidizing agents such as sodium bisulfite, sodium sulfite, or ascorbic acid either alone or combined are suitable stabilizing agents. Also used are citric acid and its salts and sodium EDTA. In addition parenteral solutions can contain preservatives, such as benzalkonium chloride, methyl- or propyl-paraben, and chlorobutanol.

Suitable pharmaceutical carriers are described in Remington's Pharmaceu ical Sciences. A. Osol, a standard reference text in this field.

Useful pharmaceutical dosage-forms for administration of the compounds of this invention can be illustrated as follows:

Capsules A large number of unit capsules are prepared by filling standard two-piece hard gelatin capsules each with 100 milligrams of powdered active ingredient, 175 milligrams of lactose, 24 milligrams of talc, and 6 milligrams magnesium stearate. A mixture of active ingredient in soybean oil is prepared and injected by means of a positive displacement pump into gelatin to form soft gelatin capsules containing 100 milligrams of the active ingredient. The capsules are washed and dried. Tablets

A large number of tablets are prepared by conventional procedures so that the dosage unit is 100 milligrams of active ingredient, 0.2 milligrams of colloidal silicon dioxide, 5 milligrams of magnesium stearate, 275 milligrams of microcrystalline cellulose, 11 milligrams of comstarch and 98.8 milligrams of lactose. Appropriate coatings may be applied to increase palatability or delay absorption.

Injectable A parenteral composition suitable for administration by injection is prepared by stirring 1.5% by weight of active ingredient in 10% by volume propylene glycol and water. The solution is made isotonic with sodium chloride and sterilized.

Suspension An aqueous suspension is prepared for oral administration so that each 5 milliliters contain 100 milligrams of finely divided active ingredient, 200 milligrams of sodium carboxymethyl cellulose, 5 milligrams of sodium benzoate, 1.0 grams of sorbitol solution, U.S.P., and 0.025 milliliters of vanillin. "Consisting essentially of" in the present disclosure is intended to have its customary meaning: namely, that all specified material and conditions are very important in practicing the invention but that unspecified materials and conditions are not excluded so long as they do not prevent the benefits of the invention from being realized.