The present invention relates to the use of azanaphthalenes for preparing a medicament and to pharmaceutical compositions containing the azanaphthalenes for suppressing the immune response. In particular it relates to the use of spiro azanaphthalene derivatives, naphthyridines and tiricyclic quinoline, naphthyridine and pyridop raz ne derivatives.

The preparation of the spiro [cyclopentane]- quinolinedione is described in Che . Pharm. Bull., 17, 1290 (1969). Several additional spiroquinoline diones are disclosed in Bull. Soc. Chim. Fr ., 364 (1968). The references do not describe pharmaceutical uses for these compounds.

Japanese Patent 54152/83 discloses various naphthyridine derivatives which allegedly possess analgesic, anti-inflammatory, central nervous system depressant and diuretic effects. U.S. Patent 4,452,800 discloses various salts of 3-(n-butyl)-4-hydroxy-l- phenyl-l,8-naphthyridine-2-(lH_)-one. U.S. Patent Nos. 4,492,702 and 4,551,463 disclose the use of various naphthyridine derivatives in treating allergic reactions and in treating and preventing ulcers in mammals. There is no indication in any of these references that such compounds may provide immunomodulating activity.

The preparation of the compound 2'-methyl- pyrano-5 ' ,6* :3, 4-(2-oxo-l,2-dihydroquinoline) and its N- phenyl derivative is described in Bull. Soc. Chim. Fr . , pp. 364-9 (1968) (C.A. 68:114419c).

The present invention is drawn to the use of an azanaphthelene for preparing a medicament and to pharmaceutical compositions containing the azanaphthelene for suppressing the immune response, the azanaphthelene having the structural formula I _a , 1^ or I _c or a solvate thereof:

wherein : two of the ring groups a, b, c and d may be CH or N and the remaining two groups represent CH;

Y _a and Z _a independently represent 0 or S ;

V _a represents 0, S(0) _na , N-R ⁸ _a or C(R _a ) ₂

each R _a independently represents hydrogen, η alkyl having from 1 to 6 carbon atoms, CH2OH, C0R' _a (wherein R' represents hydrogen or alkyl having from 1

to 6 carbon atoms) or hydroxy, with the proviso that only one hydroxy group can be attached to one carbon atom; each R' _a independently is as defined for R _a

Q above, except that when V ^* _a represents 0, S(0) _na or N-R _a ,

R' _a may not be hydroxy;

R° _a is hydrogen, alkyl having from 1 to 6 carbon atoms, carboxylic acyl having from 2 to 7 carbon atoms, alkylsulfonyl having from 1 to 6 carbon atoms, carboalkoxy having from 2 to 7 carbon atoms, CONH2 , phenyl or pyridyl of which the last two may be substituted with up to three substituents Q _a , whereby each Q _a independently is hydroxy, alkyl having from 1 to

6 carbon atoms, halogen, nitro, alkoxy having from 1 to 6 carbon atoms,, tr if luoromethyl, cyano, cycloalkyl having from 3 to 7 carbon atoms, alkenyloxy having from 3 to 6 carbon atoms, alkynyloxy having from 3 to 6 carbon atoms,

S(0)„ na -R a_ {wherein na is as defined above and R ⁹ a_ is alkyl having -from 1 to 6 carbon atoms}, NHSO2R _a {wherein R ⁹ _a is as defined above}, NHS0 ₂ CF ₃ , S0 ₂ NH ₂ , COR ¹⁰ _a {wherein R ¹⁰ _a is OH, NH ₂ or 0R ⁹ _a (wherein R ⁹ _a is as defined above)}, O-B _a -COR ¹⁰ _a {wherein B _a is alkylene having from 1 to 4 carbon atoms and R _a is as defined - above}, or NHCOR ^** - ^** ^ {wherein R _a is hydrogen, alkyl. having from 1 to 6 carbon atoms, alkoxy having from 1 to

6 carbon atoms, COR i ¹⁴ _> 1 _

C,l (wherein R ^XA d_ is hydroxy or alkoxy having from 1 to 6 carbon atoms) or NHR ^X _a (wherein R _a is hydrogen or alkyl having 1 to 6 carbon atoms)};

R _a and R _a may be the same or different, and are hydrogen, alkyl having from 1 to 6 carbon atoms, halogen, nitro, alkoxy having from 1 to 6 carbon atoms, trifluoromethyl, alkylthio having 1 to 6 carbon atoms or cyano; na is 0, 1 or 2; ra is 0, 1 or 2; qa is an integer of from 1 to 5; and

A _a is phenyl, naphthyl, indenyl, indanyl, 2-, 3- or 4-pyridyl, 2-, 4-, 5- or 6-pyrimidyl, 2- or 3- pyrazinyl, 2- or 3-furyl, 2- or 3-thienyl, 2-, 4- or 5- imidazolyl, 2-, 4- or 5-thiazolyl or 2-, 4- or 5- oxazolyl, any of which may be substituted with up to three substituents Q _a as defined herein above;

wherein X^ is CH or N;

Y _j ., is hydrogen, hydroxy, benzyloxy, amino , sulfamyl, halogen, nitro, alkyl having from 1 to 6 carbon atoms, alkoxy having from 1 to 6 carbon atoms, carboxylic acyl having from 2 to 6 carbon atoms, alkyl-S (0 )__.£- having from 1 to 6 carbon atoms wherein mb is 0, 1 or 2, t ifluoromethyl , trif luoromethylthio, or COOA^ wherein A^ is hydrogen, alkyl having from 1 to 6 carbon atoms or a cation derived from a pharmaceutically acceptable metal or an amine;

Z is hydrogen, hydroxy, halogen, alkyl having from 1 to 6 carbon atoms, alkoxy having from 1 to 6 carbon atoms, hydroxyalkyl having from 1 to 6 carbon atoms, or carboxylic acyloxy having from 2 to 6 carbon atoms;

R _b is alkenyl having from 2 to 10 carbon atoms, alkynyl having from 2 to 10 carbon atoms, cycloalk l having from 3 to 7 carbon atoms, cycloalkenyl having from 5 to 8 carbon atoms, 2-, 3- or 4-pyridyl, 2-,4- or 5- pyri idyl, 2- or 3-thienyl, 2- or 3-furanyl, carboxylic acyl having from 2 to 6 carbon atoms or alkyl having from 1 to 10 carbon atoms which may be substituted with -COOH, hydroxy, halogen, alkoxy having from 1 to 6 carbon atoms, phenyl, 2-, 3- or 4-pyridyl, 2-, 4- or 5-pyrimidyl, 2- or 3-thienyl, 2- or 3-furanyl, carboxylic acyl having from 2 to 6 carbon atoms, cycloalkyl having from 3 to 7 carbon atoms or carboxylic acyloxy having from 1 to 6 carbon atoms;

R _b is hydrogen, carboxylic acyl having from 1 to 6 carbon atoms, alkenyl having from 3 to 8 carbon atoms, alkynyl having from 3 to 8 carbon atoms, alkyl having from 1 to 6 carbon atoms, R ³ _b R ⁴ _b N(CH ₂ ) _nb - (wherein R ³ _b and R ⁴ _b are hydrogen, alkyl having from 1 to 6 carbon atoms or may be joined to complete a piperidine, orpholine, piperazine or pyrrolidine ring and nb is an integer of from 2 to 6), hydroxyalky 1 having from 2 to 6 carbon atoms, dihydroxyalkyl having from 2 to 6 carbon atoms, hydroxyalkoxyalkyl having from 2 to 8 carbon atoms, or a cation derived from a pharmaceutically acceptable metal or an amine;

lerem :

A _c is

? *c' A "

B is independently oxygen or sulfur;

R 1 _C -R 8 _c may be the same or different and are hydrogen or alkyl having from 1 to 6 carbon atoms or two adjacent R 1 _C ~R 8 _c substituents may be combined to form an additional carbon to carbon bond; rc and mc may be the same or different and are

0 or one; the ring labeled Q _Q may optionally contain up to two additional double bonds; nc is 0, 1 or 2; _c and X _c may be the same or different and are hydrogen, hydroxy, alkyl having from 1 to 6 carbon atoms, halogen, nitro, alkoxy having from 1 to 6 carbon atoms, tri-f luoromethyl,

cyano, cycloalkyl having from 3 to 7 carbon atoms, alkenyloxy having from 3 to 6 carbon atoms, alkynyloxy having from 3 to 6 carbon atoms, S(0) _pC -R ^x _c {wherein pc is 0, 1 or 2 and R 11 _c is alkyl having from 1 to 6 carbon atoms},

NHS0 ₂ R ^lx _c {wherein R ¹¹ .-. is as defined above},

NHS0 ₂ CF ₃ , NHCOCF3, S0 ₂ NH ₂ , C0R ¹² _c {wherein R ¹² _c is OH, NH ₂ or 0R ^1;L _C (wherein R ^1:L _C is as defined above)}, 0-D _c -COR ¹² _c {wherein D _c is alkylene having from 1 to 4 carbon atoms and R _c is as defined above}, or NHC0R ¹³ _c {wherein R ¹³ _c is hydrogen, alkyl having from 1 to 6 carbon atoms, alkoxy having from 1 to 6 carbon atoms,

COR ¹⁴ _c (wherein R _c is hydroxy or alkoxy having from 1 to 6 carbon atoms) or NHR ¹⁵ _C

(wherein R _c is hydrogen or alkyl having from

1 to 6 carbon atoms)}, or phenoxy {wherein the benzene ring may, be substituted with any of the other substituents W and _c };

Y _c and Z _c may be the same or different and are

CH or N;

V _c is phenyl, naphthyl, indenyl, indanyl, 2-,

3- or 4-pyridyl, 2-, 3- or 5-pyr imidinyl , 2- or

3-thienyl, 2- or 3-furyl or 2-, or 4- or

5-thiazolyl, any of which may be substituted with W and X as defined above; and

R 9 ⁷ _C and R in are independently hydrogen or alkyl having from 1 to 6 carbon atoms.

The compounds of formulae la, lb and Ic can exist in unsolvated as well as solvated forms, including hydra ted forms. In general, the solvated forms, with pharmaceutically acceptable solvents such as water, ethanol and the like are equivalent to the unsolvated forms for purposes of the invention.

Certain compounds of the invention may exist in isomeric forms. The invention contemplates all such isomers both in pure form and in admixture, including racemic mixtures.

The azanaphthalenes defined above are known as possessing anti-allergy and/or anti-inflammatory activity. According to the present invention these compounds possess immunosuppressive activity, which was not to be expected on the basis of the prior art.

The compounds of formula la are disclosed in European published application No. 84114974.3 (European patent publication No. 0 144 996 A2 ) , and are described as having anti-allergy and an ti -inflammatory activities.

The compounds of formula lb include those disclosed in U.S. Patent Nos. 4,452,800, 4,492,702 and 4,551,463 and the pharmaceutically acceptable metal or amino salts of the compound 3-(n-butyl)-4-hydroxy-l- phenyl-1, 8-naphthyridine-2( lH_)-one which is disclosed in Japanese patent public disclosure (Kokai) 116495/77, September 29, 1977, now Japanese Patent 54152/83.

The compounds of formula Ic are disclosed in the European Published Patent Application No. 84105923.1 (publication number: 0 127 135). As disclosed in the European published application No. 84105923.1 (European patent publication No. 0 127 135), these compounds possess anti-allergy and anti-inflammatory activities.

A preferred subgenus of compounds of formula I _a is that wherein Y _a and _a are both oxygen.

Preferably, a, b and c represent CH and d is either CH or N. A further preferred feature is that ra is zero, i.e. the group A _a is directly attached to the ring-nitrogen atom, qa is preferably ^" 2, 3 or 4, V _a most preferably is CH ₂ or 0 and R _a and R _a are both hydrogen.

Particularly preferred are compounds of the structural formula II _a :

wherein d is CH or N, qa is 2, 3 or 4 and A _a , V _a , R_ and R' _a are as defined above.

When utilized herein and in the appended claims the below listed terms, unless specified otherwise, are defined as follows: halogen - comprises fluorine, ^* chlorine, bromine and iodine; alkyl and alkoxy - comprises straight and branched carbon chains containing from 1 to 6 carbon atoms; alkenyloxy - comprises straight and branched carbon chains containing from 3 to 6 carbon atoms and comprising a carbon to carbon double bond; and alkynyloxy - comprises straight and branched carbon chains containing from 3 to 6 carbon atoms and comprising a carbon to carbon triple bond.

The compounds of the invention include a - - substituent wherein the R _a 9 ^{r ou} P ^s roay vary independen tly . Thus , for example , when ra or qa equa ls 2 the fo llowing pa tterns of substitution ( wherein hydrogen and CH ₃ are used to represent any substi tuents R_ ) are

contemplated: -C(CH ₃ ) ₂ CH ₂ ~, -CH ₂ C(CH ₃ ) ₂ -, -CH ₂ CH(CH ₃ )-, -CH(CH ₃ )CH ₂ -, -(C(CH ₃ )H) ₂ - and the like. In addition when ra or qa equals 2, substituents such as -C(CH ₃ ) ₂ CH(C ₂ H ₅ )-, -CH(CH ₃ )CH(C ₂ H ₅ ) are also contemplated.

It is obvious to one of ordinary skill in the art that due to problems of stability there are limitations involving the R _a and R' _a groups. One limitation is that neither R _a can be a hydroxy group attached to the carbon alpha to the ring nitrogen atom. Another limitation is that the R _a and R' _a groups cannot both be hydroxy groups attached to the same carbon atoms.

Certain compounds of the invention may exist in isomeric forms. The invention contemplates all such isomers both in pure form and in admixture, including racemic mixtures. In the structural formulas I _a and II _a herein, when V _a represents a hetero atom in the spiro ring, ^v _a .-is attached directly to the spiro carbon atom, i.e., the carbon atom identified as number 3 in structural formula I _a .

The preferred compounds of formula I _a summerized as follows:

compounds of formula I _a wherein ϊ _a and Z _a are both oxygen and/or

ra is zero and/or

R _a and R _a are both hydrogen and/or

qa is 2, 3 or 4 and/or

R _a and R' _a independently are hydrogen , methyl , ethyl , propyl , isopropyl , n-butyl or iso-butyl and/or

A _a is phenyl or phenyl substituted with one or two substituents Q, and/or

V is 0, S(O) or N-R ^a preferably 0;

wherein all of a, b, c, and d are CH or

d is N and a, b and c are CH.

Representative compounds of formula I _a are exemplified below in Table I:

TABLE I

Compound

No. d_ a_ a __a _ m.p. (°C)

1 N CH phenyl 0 0 CH ₂ trimethylene 174-178

2 N CH 3-hydroxy 0 0 CH ₂ trimethylene 218-220 phenyl

3 N CH 3-methoxy 0 0 CH ₂ trimethylene 159-160.5 phenyl

4 CH CH phenyl 0 0 CH ₂ trimethylene 168-168

5 N CH 3 , 4-chloro 0 0 CH ₂ trimethylene 143-145.5 phenyl

6 N CH 4-chloro 0 0 CH ₂ trimethylene 168.5-172 phenyl

Compound

No. d_ a_ ~ -a - ^C ( ^R, a)2(C , _a ) _a - m.p. (°C)

7 N CH 4-methyl 0 0 CH ₂ trimethylene 177-178.5 phenyl

8 N CH 3-chloro 0 0 CH ₂ trimethylene 165-167 phenyl

9 N CH 3-chloro s 0 • CH ₂ trimethylene 168-170 phenyl

10 N CH phenyl s 0 CH ₂ trimethylene 188-189.5

11 N CH 3-ethyloxalyl- • 0 0 CH ₂ trimethylene 158-160 amino phenyl

12 N CH 3-fomylamino- 0 0 CH ₂ trimethylene 222-224 phenyl

13 N CH 3-aminophenyl 0 0 CH ₂ trimethylene 200-202

14 N CH 3-(ethyloxy- 0 0 CH ₂ trimethylene 103-105 carbonyl- methoxy)phenyl

15 N CH phenyl 0 0 0 trimethylene 241.5-2.3 (1/3 hydrat

16 N CH phenyl 0 0 0 ethylene 233-235.5

18 N CH phenyl 0 0 s trimethylene

19 N CH 3,4-dichloro 0 0 0 tetrameth lene phenyl

20 N CH 3-chloro- 0 0 0 tetramethylene 158.5-160 phenyl

21 N CH 4-chloro- 0 0 0 tetramethylene 229-231.5 phenyl (hemihydrat

22 N CH 3-methoxy- 0 0 0 tetramethylene 181-183 phenyl

23 N CH 4-methoxy 0 0 0 tetramethylene phenyl

Preferred compounds of formula I _b are as follows:

The preferred value for X _b is CH.

The preferred values for Y are hydrogen, methoxy, trif luoro ethyl , methylthio; the more preferred value is hydrogen.

The preferred values for Z _b are hydrogen and methyl .

The preferred values for R _b are rv-alkyl having from 3 to 5 carbon atoms, alkenyl having from 3 to 4 carbon atoms, omega -hydroxyalkyl having 2 to 4 carbon atoms, and omega-carboxylicacyloxyalkyl having from 6 to 9 carbon atoms; the most preferred values are _rv-butyl, propen-2-yl, 2-hydroxyethyl, 3-hydroxypropyl and 4- propanoyloxybutyl .

The preferred values for R _b are hydrogen, carboxylic acyl of from 2 to 4 carbon atoms, hydroxyalkyl of from 2 to 4 carbon atoms, R _b R _b N(CH ₂ ) _nb ~ (wherein R and R _b are each independently hydrogen or alkyl having from 1 to 6 carbon atoms and nb is an integer from 2 to 6 carbon atoms) and the cations derived from sodium, potassium, calcium, ethanolamine , N-methylglucamine , diethanolamine, ethylenediamine, tr is-( ydroxymethyl )- aminomethane and lysine; the most preferred values are hydrogen, ethanoyl, propanoyl, 2-hydroxyethyl, and the cations derived from sodium, N-methylglucamine and lysine .

A preferred subgenus of compounds of formula I _b are compounds of formula H5J

^Ix b wherein M _b is a cation derived from a pharmaceutically acceptable non-toxic metal or an amine. The preferred values for M _b are the cations derived from sodium, potassium, calcium, ethanolamine, N-methylglucamine, diethanolamine, ethylenediamine, tr is- (hydroxymethyl) aminomethane and lysine. The more preferred values for are the cations derived from sodium, N-methylglucamine and lysine.

Preferred compounds for use in the present invention include com ounds havin the formulae III -IX _b :

HI_ IV-.

VI.

VII.

VIII.

IX. wherein R _h is hydrogen or the sodium cation

The compounds of formula I _b are substituted 1, 8-naphthyr idines and 1,5 , 8-azanaphthyr idines and may exist as solvates, for example as hydrates. These compounds include salts formed at the 4-hydroxy group of 3- (n -butyl )-4-hydroxy-l-phenyl-l , 8-na hthyr i dine -2 ( 1H - one .

The sodium and potassium salts of this inven¬ tion can be readily prepared by reacting the appropriate compound, e.g., 3-(n-butyl )-4-hydroxy-l-phenyl-l , 8-

_ naphthyr idine-2 ( lH_)-one, with respectively, sodium hydroxide solution or potassium hydroxide solution.

The amine and amino acid salts can be prepared by reacting the appropriate amine or amino acid with the desired hydroxylated compound, e.g., 3-(n-butyl )-4- hydroxy-l-phenyl-1, 8-naphthyr idine-2 ( 1H_) -one, in a compa table organic solvent, e.g. methanol.

The calcium salt can be prepared by reaction of the sodium salt with calcium chloride solution.

The aluminum, bismuth, chromium, copper, iron, magnesium, manganese and zinc salts of this invention can be prepared by methods known to those of skill in the art.

When utilized herein and in the appended claims the below listed terms, unless specified otherwise, are defined as follows: halogen - fluorine, chlorine, bromine and iodine; alkyl - straight and branched carbon chains containing from 1 to 10 carbon atoms; hydroxyalkyl and dihydroxyalkyl having from 2 to 6 carbons - hydroxyalkyl and dihydroxyalkyl groups wherein the hydroxy group(s) is not substituted at the position alpha to the oxygen to which the R _b group is attached.

R _b is alkenyl and alkynyl having from 3 to 8 carbon atoms-alkenyl and alkynyl groups wherein the unsaturation is not at the position alpha to the oxygen to which the R _b group is attached.

Pharmaceutically acceptable metal and amine - metals and amines that are generally recognized as being non toxic, such as sodium, potassium, calcium, aluminum, N-methylglucamine, lysine and the like.

When used in the definition of compounds of formula I _c the below listed terms, unless specified otherwise, are defined as follows: halogen - fluorine, chlorine, bromine and iodine;

alkyl and alkoxy - comprised of straight and branched carbon chains containing from 1 to 6 carbon atoms; alkenyloxy - comprised of straight and branched carbon chains containing from 3 to 8 carbon atoms and comprising a carbon to carbon double bond; and alkynyloxy - comprised of stra ight and branched carbon cha ins conta in ing from 3 to 8 carbon atoms and comprising a carbon to carbon tr iple bond .

The compounds of the invention may possibly contain two different "B _c " substituents. It is intended that both may simultaneously be oxygen or sulfur, or that either may be oxygen or sulfur.

In certain- compounds of the invention, the ring labeled Q _c , may contain up ^' to two additional double bonds which double bonds are formed by the combination- of two ι adjacent substituents, R _C ~R _c - Thus, for example, when Q is a 7 membered ring (rc and mc are both equal to one) it may. contain 3 double bonds. When multiple double bonds are present, they will be non-cumulated double bonds.

The compounds of the invention are comprised of a -(C ^R9 _c R ¹⁰ _c ) _nc - substituent wherein the R ⁹ _C and R ¹⁰ _c groups may vary independently. Thus, for example, when nc equals 2 the following patterns of substitution (wherein hydrogen and CH are used to represent any substituent, R ⁹ _C or R _c ) are contemplated: -C(CH ₃ ) ₂ CH ₂ -, -CH ₂ C(CH ₃ ) ₂ -, -CH ₂ CH(CH ₃ )-, -CH(CH ₃ )CH ₂ -, -(C(CH ₃ )H) ₂ - and the like. In addition when nc equals 2, substituents such as -C(CH ₃ ) ₂ CH(C ₂ H ₅ )-, -CH(CH ₃ )CH(C ₂ H ₅ )-, -CH(_i_-C ₃ H ₇ )CH(C ₂ H ₅ )- are also contemplated.

Subgenera of compounds of formula I _c are

compounds wherein B is oxygen;

compounds wherein B is oxygen and A_ is A'

compounds wherein nc is zero and/or Y _c is CH;

compounds having the structural formulas II _C ,

III,,, IV,,, VI., VII. or VIII

H ⁴

^II] _

VI

wherein W _c , V _c , X _c , Z _c , R1 _c -R8° _c , rc and mc are as defined herein;

compounds of formula III

wherein W _c , X _c , R _c , R _C , R ³ _C , and R ⁴ _c are as defined above, wherein preferably R ^x _c , R _C , R ³ _C and R ⁴ _C are hydrogen or methyl;

in particular compounds of formula II

wherein W _c , X _c , Z ₍ Vc' R „ to R ^c C rc and mc are as defined above

wherein preferably

- _c is N and/or

rc and mc are both zero or one or

the sum of rc and mc is one -and/or

B _c is oxygen and/or

V„ is of formula IX, compounds of formula IV

1 p wherein W _c , X _c and R ^x _c -R° _c are as defined above, wherein preferably

R 1 _C ~R ^~ _< -. are hydrogen or methyl, especially hyrogen.

or one of R 1 _C -R 8 _c is methyl and the rest are hydrogen and/or

_c is 3-chloro and X _c is hydrogen, chlorine or fluorine or

W _c is 3-methoxy and X _c is hydrogen or fluorine or

W _c and X _c are both hydrogen;

compounds of formula VI I _c

wherein W _c , X _c , V _c , R ^x _c , R ² _C , R ³ _C and R ⁴ _C are as defined above;

compounds of formula VIII _C

wherein W _c , x ^' _c , R _c , R _c r R _c and R _c are as defined above, wherein preferably

W c- is 3-chloro and X_ is hydrogen, chlorine or fluorine or

_c is 3-methoxy and X _c is hydrogen or fluorine or _c and X are both hydrogen.

Representative compounds of formula I _c are exemplified by the following compounds:

3,5-dihydro-5-phenyl-furo [3,2-c] [1 ,8] naphthyr idin-4 [2_Hj- one;

3,5-dihydro-5-phenyl-thieno [3,2-c] [1,8] -naphthyridin-

4[2jJ]-one;

6-phenyl-2,3,4,6-tetrahydro-pyrano [3,2-c] [1,8]- naphthyridin-5-one;

2-methyl-3,5-dihydro-5-phenyl-furo [3,2-c] [1,8]- naphthyr idin-4 [2_HJ -one ;

3,9-dihydro-9-phenyl-furo [2 ,3-b] [1 , 8] naphthyr idin-4 [2_HJ- one;

3,9-dihydro-9-(p-methylphenyl)-furo [2 ,3-b] [ 1,8] naphthy- r idin-4 [2jl_] -one;

3 , 9-dihydro-2-methy 1-9-phenyl-furo [2 , 3-b] [1,8] naphthy-

3,5-dihydro-5-(p-methylphenyl )-furo [3,2-c] [1,8] naphthy- r idin-4 [2_H_] -one ;

3,5-dihydro-5-(p-fluorophenyl)-furo [3,2-c] [1,8] naphthy- r idin-4 [2_H_]-one;

3,5-dihydro-5-(m-methoxyphenyl )-furo [3,2-c] [1,8] naphthy- r idin-4 [2_H]-one;

3,5-dihydro-5-(m-meth lthiophenyl )-furo [3,2-c] [1,8] - naphthyridin-4 [2_H_] -one;

3,9-dihydro-9-(p-fluorophenyl)-furo [2 ,3-b] [1,8] naphthy- r idin-4 [2_H_]-one;

3, 9-dihydro-9-(m-methoxyphenyl)-furo [2 ,3-b] [1,8] naphthy- r idin-4 [2jH] -one ;

3,9-dihydro-9-(m-methylthiophenyl)-furo [3,2-c] [1,8] - naphthyr idin-4 [2_H] -one ;

3,5-dihydro-5-(3, 4-dichlorophenyl )-furo [3 ,2-c] [1,8]- naphthyr idin-4 [2_H]-one;

3,5-dihydro-5-(3, 4-dichlorophenyl )-2-meth l-furo

[3,2-c] [1 ,8] -naphthy idin-4 [2HJ -one;

3,5-dihydro-5-(4-chlorophenyl)-furo [3,2-c] [1,8]- naphthyr idin-4 [2_H]-one;

3,5-dihydro-5-(3-chlorophenyl)-furo [3,2-c] [1,8]- naphthyr idin-4 [2jJ_] -one;

3,5-dihydro-5-( 3-chlorophenyl) -2 -me th 1-furo [3,2-c] [1,8] ^• naphthyr idin-4 [2_Hj-one;

3,5-dihydro-5-(4-fluorophenyl)-2-methyl-furo [3,2-c] [1,8]' naphthyridin-4 [2_H_] -one;

3,5-dihydro-5-( 3-methoxyphenyl)-2-meth 1-furo

[3,2-c] [l,8]-naphthyridin-4[2_H]-one;

3,5-dihydro-5-(3,5-dichlorophenyl)-furo [3,2-c] [1,8]- naphthyr idin-4 [2_H_]-one ;

3 , 5-dihydro-5- ( 3 , 5-dichlorophenyl ) -2 -me thy 1-furo

[3,2-c] [ 1,8] -naphthyr idin-4 [2HJ -one;

3,5-dihydro-5-ρhenyl-2 ,2-dimethy 1-furo [3,2-c] [1,8] - naphthyr idin-4 [2_H_]-one;

3,5-dihydro-5-( 3-methylsulfonylaminophenyl ) -2-meth 1- furo [3,2-c] [1,8] -naphthyr idin-4 [2H_]-one;

3 , 5-dihydro-5- ( 3-methylsulfonylaminophenyl ) -furo

[3,2-rc] [1,8] -naphthyr idin-4 [2H_]-one;

3,9-dihydro-9-(3,4-dichlorophenyl)-furo [2 ,3-b] [1,8] - naphthyr idin-4 [2_H_]-one;

3 , 9-dihydro-9- ( 4-chlorophen 1 ) -furo [2 , 3-b] [1,8]- naphthyr idin-4 [2_H_]-one;

3 , 9-dihydro-9- ( 3-chlorophenyl ) -furo [2 , 3-b] [1,8]- naphthyr idin-4 [2jH_]-one;

3, 9-dihydro-9-( 3-chlorophenyl )-2-methy 1-furo [2 , 3-b]' [1,8] naphthyr idin-4 [2_HJ -one;

3 , 9-dihydro-9- ( 4-f luorophenyl ) -2 -me th 1-furo [2 , 3-b] [1,8] naphthyr idin-4 [2_H_]-one;

3 , 9-dihydro-9- ( 3-methoxyphenyl ) -2-methy 1-furo

[2,3-b] [l,8]-naphthyridin-4 [2H_]-one;

3 , 9-dihydro-9- ( 3 , 5-dichloropheny 1 ) -furo [2 , 3-b] [1,8]- naphthyr idin-4 [2jl_]-one;

3 , 9-dihy dro-9- ( 3 , 5-dichlorophenyl ) -2-methy 1-furo

[2 , 3-b ] [1,8] -naphthyr idin-4 [ 2HJ -one ;

3 ,9-dihydro-9-( 3-methylsulfonylaminophenyl) -2-meth 1- furo[2,3-b] [1 ,8] -naphthyr idin-4 [2HJ -one ;

6-(4-chlorophenyl)-2 ,3,4, 6-tetrahydro-5_H_-pyrano [3,2-c]-

[1, 8]naphthy idin-5-one;

6-(3, 4-dichlorophenyl )-2,3, 4,6-tetrahydro-5l*-pyrano

[3,2-c] [1, 8] naphthyridin-5-one;

6- ( 4-methoxyphenyl ) -2 , 3 , 4 , 6-tetrahy dro-5Jϊ_-pyrano

[3,2-c] [1, 8] naphthyr idin-5-one;

6-( 4-methylphenyl)-2,3,4, 6-tetrahydro-5_H_-pyrano

[3,2-c] [1, 8] naphthyr idin-5-one ;

10-( 3,4-dichlorophenyl )-2,3,4, 10-tetrahydro-5_H_-pyrano-

[2, 3-b] [l,8]naphthyridin-5-one;

10-( 4-methoxyphenyl ) -2 , 3 , 4, 10-tetrahydro-5JH_-pyrano-

[2,3-b] [1 ,8] naphthyr idin-5-one ;

10-( 4-chlorophenyl ) -2 , 3 , 4 , 10-tetrahydro-5_H_-pyrano-

(2,3-b] [1,8] naphthyridin-5-one ;

10-( 4-methylphenyl)-2,3,4,10-tetrahydro-5_H_-pyrano-

(2,3-b] [1,8] naphthyr idin-5-one;

10-phenyl-2 ,3,4, 10-tetrahydro-5_H_-pyrano- [2 , 3-b] [1,8]- naphthyr idin-5-one ;

7-phenyl-3,4,5 , 7-tetrahydro-oxepino [3,2-c] [1,8]- naphthyridin-6 [2_Hj-one;

7-( 4-chlorophenyl )-3 , 4,5 , 7-tetrahydro-oxepino-

[3,2-c] [l,8]-naphthyridin-6[2_H]-one;

7-( 3-chlorophenyl) -3 ,4 ,5 , 7-tetrahydro-oxepino-

[3,2-c] [l,8]-naphthyridin-6 [2_H_]-one;

7-( 3-methoxyphenyl )-3 , 4,5 , 7-tetrahydro-oxepino-

[3,2-c] [1 ,8] -naphthyr idin-6[2HJ -one; and

7-( 3-hydroxyphenyl )-3 , 4,5 , 7-tetrahydro-oxepino-

[3,2-c] [l,8]-naphthyridin-6 [2H_]-one.

The compounds are useful in the treatment of autoimmune and other immunological diseases including graft rejection in which T cell proliferation is a contributing factor to the pathogenesis of disease. The effectiveness of these compounds as immunosuppressing agents may be demonstrated by the following tests which involve the inhibition of T cell functions using these compounds.

GRAFT VS. HOST REACTION (GVHR) To induce a GVHR, C57 Bl/6XA/J(B6AF1) male mice were injected intravenously with parental (C57B1/6J) spleen and lymph node cells. The test compound was then administered orally for 12 days beginning on the day prior to the cell transfer. On the day following the last treatment, the animals were sacrificed, and their spleens were excised and weighed. The enlargement of the spleen of the host is a result of a GVHR. To some extent it is the host's own cells which infiltrate and enlarge the spleen although they do this because of the presence of graft cells reacting against the host. The amount of spleen enlargement, splenomegaly, is taken as a measure of the severity of the GVHR.

In carrying out the GVHR the animal in the experimental group is injected with parental cells, cells of the same species but of different genotype, which cause a weight increase of the spleen. The animal in the control group is injected with syngeneic cells, genetically identical cells which do not cause a weight increase of the spleen. The effectiveness of the test compound administered to the mice in the experimental group is measured by comparing- the spleen weight of the untreated and treated GVH animal with that of the syngeneic control.

ED _3Q : dosage [mg/kg] of test compound administered daily yielding a 30% decrease of spleen weight as compared to the untreated animals.

Test Compound ^ΞD 30 - ^m *-. g-

( R,S ) -l-Phenyl-3 ' , 4 ' , 5 ^• , 6 ' -Tetrahydro- 100

Spiro- [ 1 , 8-Naphthyr idine-3 , 2 ' - [2_H_] -Pyran ] -2,4-Dione 1/4 Hydrate

1 ^• -( 3-Chlorophenyl )-Spiro [Cyclopentane- 100

1 , 3 ' - [ 1 , 8 ] Naphthyr idine ] -2 ' , 4 ^• - ( 1 ^* _H_) -

Dione

4-Acetoxy-l-Pheny ^' l-3- ( 2-Propenyl ) -1 , 8- 25

Naphthyr idin-2 ( 1H_) -One

SPLENIC ATROPHY The immunosuppressive activity of the compounds may also be shown by a decrease in spleen weight after dosing BDF^ mice orally with the drug for seven (7) consecutive days. The mice are sacrificed on the ^" eighth day. The percent decrease in spleen weight is measured for each dosage level. In this procedure l'-(3- chlorophenyl ) -spiro- [cyclopen ane-1 ,3 '- [1 ,8] - naphthyridine] -2 ', 4'-( 1 '_HJ -dione provided a 30% spleen weight decrease at a dosage level of 100 mg/kg .

GRAFT VS. HOST REACTION (GVHR)

To induce a GVHR, C57 Bl/6XA/J( B6AF1) male mice were injected intraperitoneally with parental (C57B1/6J) spleen cells. 3-(n-Butyl )-4-hydroxy-l-phenyl-l,8- naphthyridine-2 ( lH)-one sodium salt (test drug) was then administered orally for 8 days beginning on the day of cell transfer. On the day following the last- treatment, body weights were obtained, the animals were sacrificed, and their spleens were excised and weighed. The enlargement of the spleen of the host is a result of a GVHR. To some extent it is the host's own cells which

infiltrate and enlarge the spleen although they do this because of the presence of graft cells reacting against the host. The amount of spleen enlargement, splenomegaly, is taken as a measure of the severity of the GVHR.

The GVHR is expressed below as the spleen index, the ratio of the weight of the spleen to the total weight of the animal in the experimental group compared with the same ratio in the control group.

spleen index=weight of experimental spleen/total body weight weight of control spleen/total body weight

In carrying out the GVHR the animal in the experimental group is injected with parental cells, cells of the same species but of different genotype, which cause a weight increase of the. spleen. The animal in the control group is injected with syngeneic cells, genetically identical cells,- which do not cause a weight increase of the spleen. The effectiveness of the sodium salt administered to the mice in the experimental group is measured against a spleen index .scale. The scale goes from a spleen index of 1.0 for complete immunosuppression to a spleen index of 2.6 for a lack of immunosuppression.

The sodium salt at 100 mg/kg gave a spleen index of 1.6.

According to the same test procedure BDFI mice o were injected intravenously with 1 X 10° C ₅₇ Bl/6 spleen and lymph node cells and the test drug was administered for 10 days . The following results were obta ined:

Per Cent Inhibition

Test Drug Cose Spleen Spleen i g/kg ⁾ Enlargement Index

3- ( n-bu ty 1 ) -4-hy droxy-1-pheny 1- 100 71 71 1 , 8-naphthyr idine-2 ( lH_)-one

3- ( n-buty 1 ) -4 [2- ( dime th lamino ) 50 54 43 ethox ] -1-phenyl-l , 8-naphthyr idine -2 ( 1H_) -one hydrochloride

3- (n-buty 1 ) -1- ( 2 , 4-di fluorophenyl ) - 100 11 10 4-hydroxy-l , 8-naphthyr idin-2 ( 1H_) -one

The following result where obtained when a modification of the above test procedure was used, wherein BDFI mice were injected intravenously with 1 X

Q

10° C 57 Bl/6 spleen cells and the mice were pretrea ted da ily with drug for 7 days pr ior to and fol lowing the inj ection of parenta l spleen cells ( tota l of 16 days ) :

Per Cent Inhibition

Test Drug Dose Spleen Spleen

(m gr P«o . ) Enlargement Index

3- ( n-butyl ) -4-hydroxy-l-phenyl- 100 100 80

1 , 8-naphthyr idine-2 ( lH_)~one

3- (n-butyl) -4 [2- (dimethy lamino) 50 52 19 ethoxy] phenyl-1 , 8-naphthyr idine -2 ( lH_)-one hydrochloride

3- (n-butyl )-l-( 2 , 4-dif luorophenyl )- 100 37 37

4-hydroxy-l , 8-naphthyr idin-2 ( 1H)

-one

7- ( n-butyl )-8-hydroxy-5-phenyl-pyrido 100 75 81

[2 , 3-b] pyrar in-6 ( 5H_) -one

T CELL MITOGENIC RESPONSIVE ESS Spleen cells were obtained from six to eight week old C57 B1/6J male mice. One million viable spleen cells were cultured in triplicate in microtest II plates in the presence of 1 ug concanavalin A (Con A) or 0.25 μg phytophemagglutinin (PHA) for 72 hr at 37 °C. The total volume was 0.2 ml. One microcurie ³ H-Thyιrt idine (specific activity, 2.0 Ci/mmole) was added for the last 16 hr of incubation. The cells were harvested and processed on a mash II harvester. A stock solution of 1x10 ^ώ M of the test drug (inhibitor) was prepared in distilled water and then diluted with medium to the appropriate concentration. The test drugs at concentrations of 1, 10 and 100 μM inhibited the prolif erative responses of unfractionated murine splenocytes to the T cell mitogens. Con A and PHA as shown in the following table:

Mitogen Inhibitor

Inhibitor Concentration C\M)

1 10 100

Concanavalin A 3- (n-butyl )-4-hydroxy 74 71 70

(Con A) -l-phenyl-l,8-naphthy- idin-2 (1H) -one

3-(3-hydroxy-n-butyl) 96 78 59

-4-hydroxy-l-phenyl-

1 , 8-naphthyr idin-2

(lH_)-one

4-hydroxy-l-phenyl-3 89 66 47 -[2-(2-pyridinyl) ethyl]-1,8-naphthy- ridin-2(1H)-one

Phytohemagglutin 3-(n-butyl)-4-hydroxy 80 49 31 (PHA) -l-phenyl-l,8-naphthy- ridin-2(1H_)-one 103 102 62

4-hydroxy-l-phenyl-3 112 100 32

-[2-(2-pyridinyl) ethyl ] -1 , 8-naphthy- r idin-2 (1H_) -one

The immuno suppressive activity of the - compounds of formula I _c is shown by the following test results:

GRAFT VS. HOST REACTION (GVHR) To induce a GVHR, C57 Bl/6XA/J(B6AF1 ) male mice were injected intravenously with parental (C57B1/6J) spleen and lymph node cells. The compound 10- (4- chlorophenyl ) -2 , 3 , 4, 10-tetrahydro-5_H-pyrano [2 , 3- b] [1,8] naphthyridin-5-one (test drug) was then administered orally for 10 days beginning on the day prior to the cell transfer. On the day following the last treatment, the animals were sacrificed, and their spleens were excised and weighed. The enlargement of the spleen of the host is a result of a GVHR. To some extent it is the host's own cells which infiltrate and enlarge the spleen although they do this because of the presence of graft cells reacting against the host. The amount of spleen enlargement, splenomegaly, is taken as a measure of the severity of the GVHR.

In carrying out the GVHR the animal in the experimental group is injected with parental cells, cells of the same species but of different genotype, which cause a weight increase of the spleen. The animal in the control group is injected with syngeneic cells.

genetically identical cells which do not cause a weight increase of the spleen. The effectiveness of the test drug administered to the mice in the experimental group is measured by comparing the spleen weight of the untreated and treated GVH animal with that of the syngeneic control. The test drug reduced spleen weight by 8% as compared to the untreated animals at a dose of 100 mg/kg.

ANTI-SHEEP RED BLOOD CELL RESPONSE

The immunosuppressive activity of the compounds of formula I _c may also be shown by the inhibitionof the secretion of IgM cells in mice immunized with sheep erythrocytes. In particular, BDF^ mice are immunized intravenously with 1 x 10 sheep erythrocytes on day zero. Treatment with the test drug (oral administration) is initiated the day prior--to the immunization and is continued through day three. On day four the number of IgM secreting cells in the spleens of the treated mice are assessed by the Jerne Plaque technique, with the results expressed as a percent inhibition in comparison to untreated controls. 10-( 4-chlorophenyl )-2 , 3, 4, 10- tetrahydro-5_H_-pyrano [2 ,3-b] [1,8] naphthyr idin-5-one at 100 mg/kg per day and 9- ( 3-chlorophenyl ) -3, 9-dihydro-2- methyl-furo [2 ,3-b] [1,8] naphthyr idin-4 [2_H_] -one at 100 mg/kg per day provided about 10% and about 27-36% inhibition, respectively, in this test procedure.

As noted, European patent publication No. 0 144 966 A2 discloses that the subject compounds (formula I _a ) possess anti-allergy and anti-inflammatory activities. For example, l-phenyl-3 ', 4' ,5 ', 6' -tetrahydro-spiro- [1,8] - naphthyr idine-3,2 '-[2_H]pyran-2, 4-dione V4 hydrate has an ED5 _Q value of about 2 mg/kg p.o. in tests measuring the inhibition of anaphylactic bronchospasm in sensitized

guinea pigs having antigen-induced bronchoconstriction and an ED^ _Q value of about 19 mg/kg p.o. in tests measuring the reverse passive Arthus reaction in the pleural cavity of rats (as described by Myers et al.. Inflammation, Vol. 9, No. 1, 1985, pp. 91-98). This compound has an ED ₃₀ value of about 100 mg/kg in the GVHR test as described above. As noted, European patent publication No. 0 127 135 discloses that the subject compounds possess anti-allergy and anti-inflammatory activities. For example, 10-( 4-chlorophenyl )-2, 3, 4, 10- tetrahydro-5_H_-pyrano [2 ,3-b] [1,3] naphthyr idin-5-one at a concentration of about 10 uM provided about 57% inhibition of SRS-A release in the procedure described in Kreutner et al., European Journal of Pharmacology, Vol. Ill, 1985, pp 1-8. This compound has an ED _Q value of about 6 mg/kg p.o. in tests measuring the reverse passive Arthus reaction in the pleural cavity of rats (as described by Myers et al.. Inflammation, Vol. 9, No. 1, 1985, pp. 91-98). These results indicate that an immunosuppressive effective dose for the compounds formulae I _a , I , and I _c is several times their anti-inflammatory and anti-allergy effective doses .

The compounds of formulae I _a , I _b and I _c are orally and parenterally effective in the treatment of autoimmune and other immunological disease including graft rejection at a dosage range of 0.1 to 250 mg/kg of body weight per day, preferably 0.1 to 150 mg/kg or 25 to 150 mg/kg.

In particluar, the usual dosage range for the compounds of formula I in a 70 kg mammal is an oral dose of about 5 to 250 mg/kg, preferably 25 to 150 mg/kg, in 3 or 4 divided doses; the usual dosage range for the compounds of formula I _a in a 70 kg mammal is an oral dose of about .1

to 250 mg/kg, preferably .1 to 150 mg/kg, in 3 or 4 divided doses per day; the usual dosage range for the compounds of formulae I _c in a 70 kg mammal is a dose of about .1 to 250 mg/kg, preferably .1 to 150 mg/kg per day. The compounds may be administered by conventional routes, e.g., orally, subcutaneousl , intramuscularly, etc. Orally the compound may be administered in 3 or 4 divided doses per day. Of course, the dose will be regulated according to the potency of compound employed, the immunological disease being treated, and the judgment of the attending clinician depending on factors such as the degree and the severity of the disease state and age and general condition of the patient being treated.

To treat immunological diseases, the active compounds of formulae I _a , I _b and I _c can be administered in unit dosage forms such as tablets, capsules, pills, powders, granules, sterile parenteral solutions or suspensions, suppositories, transdermal compositions and the like. Such dosage forms are prepared according to standard techniques well known in the art.

For preparing pharmaceutical compositions from the compounds described by this invention, inert, pharmaceutically acceptable carriers can be either solid or liquid. Solid form preparations include powders, tablets, dispersible granules, capsules, cachets and suppositories. A solid carrier can be one or more substances which may also act as diluents, flavoring agents, solubilizers, lubricants, suspending agents, binders or tablet disintegrating agents; it can also be an encapsulating material. In powders, the carrier is a finely divided solid which is in admixture with the finely divided active compound. In the tablet the active compound is mixed with carrier having the necessary binding properties in suitable proportions and compacted

35

in the shape and size desired. The powders and tablets preferably contain from 5 /to about 70 percent of the active ingredient. Suitable solid, carriers are magnesium carbonate, magnesium strearate, talc, sugar, lactose, pectin, dextrin, starch, gelatin, tragacanth, methylcellulose, sodium carboxymethylcellulose, a low

/

/

melting wax, cocoa butter and the like. The term "preparation" is intended to include the formulation of the active compound with encapsulating material as carrier providing a capsule in which the active component (with or without other carriers) is surrounded by carrier, which is thus in association with it. Similarly, cachets are included. Tablets, powders, cachets and capsules can be used as solid dosage forms suitable for oral administration.

For preparing suppositories, a low melting wax such as a mixture of fatty acid glycerides or cocoa butter is first melted, and the active ingredient is dispersed homogeneously therein as by stirring. The molten homogeneous mixture is then poured into convenient sized molds, allowed to cool and thereby solidify.

Liquid form preparations include solutions, suspensions and emulsions. As an example may be mentioned water or water-propylene glycol solutions for parenteral injection. Liquid preparations can also be formulated in solution or suspension in aqueous polyethylene glycol solution. Aqueous solutions suitable for oral use can be prepared by. adding the active component in water and adding suitable colorants, flavors, stabilizing, sweetening, solubilizing and thickening agents as desired. Aqueous suspensions suitable for oral use can be made by dispersing the finely divided active component in water with viscous material, i.e., natural or synthetic gums, resins, methylcellulose, sodium carboxymethylcellulose and other well-known suspending agents.

Also included are solid form preparations which are intended to be converted, shortly before use, to liquid form preparations for either oral or parenteral administration. Such liquid forms include solutions, suspensions and emulsions. These particular solid form

preparations are most conveniently provided in unit dose form and as such are used to provide a single liquid dosage unit. Alternately, sufficient solid may be provided so that after conversion to liquid form, multiple individual liquid doses may be obtained by measuring predetermined volumes of the liquid form preparation as with a syringe, teaspoon or other volumetric container. When multiple liquid doses are so prepared, it is preferred to maintain the unused portion of said liquid doses at low temperature (i.e., under refrigeration) in order to retard possible decomposition. The solid form preparations intended to be converted to liquid form may contain, in additions to the active material, flavorants, colorants, stabilizers, buffers, artificial and natural sweeteners, dispersants, thickeners, solubilizing agents and the like. The solvent utilized for preparing the liquid form preparation may be water, isotonic ^' water, ethanol, glycerine, propylene glycol and ^' the like as well as mixtures thereof. Naturally, the solvent utilized will be chosen with regard to the route of administration, for example, liquid preparations containing large amounts of ethanol are not suitable for parenteral use.

The composition of the invention may also be deliverable transdermally. The transdermal compositions can take the form of creams, lotions and/or emulsions and can be included in a transdermal patch of the matrix or reservoir type as are conventional in the art for this purpose.

Preferably, the pharmaceutical preparation is in unit dosage form. In such form, the preparation is subdivided into unit doses containing appropriate quantities of the active component. The unit dosage form can be a packaged preparation, the package containing discrete quantities of preparation, for example, packeted tablets, capsules and powders in vials or ampoules. The unit dosage form can also be appropriate number of any of these in packaged form. The quantity of active compound in a unit dose of preparation may be varied or adjusted from 1 mg to 1000 mg according to the particular application and the potency of the active ingredient. The compositions can, if desired, also contain other therapeutic agents.

The dosages may be varied depending upon the requirements of the patient, the severity of the condition being treated and the particular compound being employed. Determination of the proper dosage for a particular situation is within the skill' of the art.. Generally, treatment is initiated with smaller dosages which are less than the optimum dose of the compound. Thereafter, the dosage is increased by small increments until the optimum effect under the circumstances is reached. For convenience, the total daily dosage may be divided and administered in portions during the day if desired.

The following examples are intended to illustrate, but not to limit, the present invention.

The term "Compound A", "Compound B" and "Compound C" refers to any one of the compounds of formula I _a (Compound A), formula I (Compound B) and formula I _c (Compound C):

Compound. A: 1'-phenyl-3' ,4' ,5' ,6'-tetrahydro- spiro-[1,8]naphthyridine]-3' ,2'-[2 _-pyran]-2,4-dione V4 hydrate,

Compound B: 3-(n-butyl )-4-hydroxy-l-( 3- me th lthiophenyl )-l, 8-naphthyr idin -2- ( lH_)-one;

3- (n-butyl) -4-hydroxy-l -phenyl -1,8- naphthy idin-2( lH_)-one;

4-acetoxy-l-pheny 1-3- (2-propenyl) -1,8- naphthyr idin-2- ( lH_)-one;

4-hydroxy-l-phenyl-3- ( 2-propenyl ) -1 , 8- naphthyridin-2-( l_H_)-one;

4-hydroxy-l- ( 3-methoxyphenyl ) -3- (2-propenyl )- 1, 8-naphthyr idin-2 ( lH)-one; l-phenyl-4-propionyloxy-3-( 4- p o ionyloxy butyl ) -1 , 8 , -naphthyr idin-2 ( 1H ) -one ;

3- (2-hydroxyethyl )-4-hydroxy-l-phenyl-l,8- naphthyr idin-2 ( lH_)-one;

3- (n-butyl )- 4- (2-hydroxy ethoxy )-l-phenyl-l ,8- naphthyr idin-2 ( lH_)-one;

4-hydroxy-l-phenyl-3-( 2-pyr idyl )-l , 8- naphthyr idin-2 ( lH_)-one; and 3- (n-butyl )-4- [2- ( 2-hydroxyethyoxy ) ethoxy] - 1-phenyl-l, 8-naphthyr idin -2 ( lH_)-one,

Compound C: 10- ( 4-chlorophenyl )-2 , 3 , 4, 10- tetrahydro-5_H_-pyrano [2 ,3-b] [1,8] -naphthyr idin -5 -one.

It is contemplated, however, that this compound may be replaced by equally effective quantities of other compounds of formulae I _a , I and I _c as defined above.

Example 1

Tablets

No. Ingredient mq/tablet mg/tablet

1 Compound A, B or C 100 500

2 Lactose USP 122 113

3 Corn Starch, Food Grade, 30 40 as a 10% paste in Purified Water

4 Corn Starch, Food Grade 45 40

5 Magnesium Strearate 3 7

Total 300 700

Method of Manufacture

Mix Item Nos. 1 and 2 in a suitable mixture for 10-15 minutes. Granulate the mixture with Item No. 3. Mill the damp granules through a coarse screen (e.g., 1/4") if needed. Dry the damp granules. Screen the dried granules if needed and mix with the Items No. 4 and mix for 10-15 minutes. Add Item No. 5 and mix for 1-3 minutes. Compress the mixture to appropriate the size and weight on a suitable tablet machine.

Example 2

Capsules

No. Ingredient mq/capsule mg/capsule

1 Compound A, B or C 100 500

2 Lactose USP 106 123

3 Corn Starch, Food GGrraaddee 40 70

4 Magnesium Strearat :ee NNFF 4 7

Total 250 700

Method of Manufacture

Mix Item Nos. 1,2 and 3 in a suitable blender for 10-15 minutes. Add .Item No. 4 and mix for 1-3 minu'tes. Fill the mixture into suitable two-piece hard gelatin capsules on a suitable encapsulating machine.

Example 3

Parenteral

Ingredient mg/vial mg/vial

Compound A or B Sterile Powder 100 500

Add sterile water for injection or bacte iostatic water for injection for reconstruction.

Example 4

In jectable

No . Ingredient mg/vial mg/vial

1. Compound A or B 100 500

2. Methylparaben 1.8 1.8

3. Propylparaben 0.2 0.2

4. Sodium Bisulfilte 3.2 3.2

5. Disodium Edetate 0.1 0.1

6. Sodium Sulfate 2.6 2.6

7. Water for Injection ^' q.s. ad 1.0ml 1.0ml

Method for Manufacture

1. Dissolve parabens in a portion (85%) of the final volume) of the water for injection at 65-70°C.

2. Cool to 25-35 °C. Charge and dissolve the sodium bisulfite, disodium edetate and sodium sulfate.

3. Charge and dissolve drug.

4. Bring the solution to final volume by added water for injection.

5. Filter the solution through 0.22 membrane and fill into appropriate containers.

6. Terminally sterilize the units by autoclaving

P/PASP0600