Pharmaceutical compositions

Pharmaceutical compositions containing a 3-hydroxypyrid-2-one or 3-hydroxypyrid one in which the hydrogen atom attached to the nitrogen atom is replaced by an aliphatic acyl group, by an aliphatic hydrocarbon group, or by an aliphatic hydrocarbon group substituted by one or, except in the case of ionizable groups, more than one substituent selected from aliphatic acyl, alkoxy, aliphatic amine, aliphatic amide, carboxy, aliphatic ester, halogen, hydroxy and sulpho groups and, optionally, in which one or more of the hydrogen atoms attached to ring carbon atoms are replaced by one of said substituents, by an aliphatic hydrocarbon group, or by an aliphatic hydrocarbon group substituted by an alkoxy, aliphatic ester, halogen or hydroxy group, but excluding compounds in which said replacement of hydrogen atoms in the compound is effected only by aliphatic hydrocarbon groups, or a salt thereof containing a physiologically acceptable ion or ions, are of value for removing toxic amounts of metals, particularly iron, from the body.

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Claims

1. A method for the treatment of a patient having a toxic concentration of a metal selected from the group consisting of iron, copper, and aluminum in the body of said patient which comprises administering to said patient a therapeutic amount of a 3-hydroxypyrid-2-one or 3-hydroxypyrid-4-one in which the hydrogen atom atached to the nitrogen atom is replaced by an aliphatic acyl group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by one or more substituents selected from aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen and hydroxy groups, and wherein one or more of the hydrogen atoms attached to ring carbon atoms can be replaced by an aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen or hydroxy group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by an alkoxy, aliphatic ester, halogen or hydroxy group, but excluding compounds in which said replacement of hydrogen atoms is effected only by aliphatic hydrocarbon groups, or a salt thereof containing a physiologically acceptable cation.

2. The method of claim 1 wherein said metal is iron or aluminum.

3. The method according to claim 1, in which the metal is iron.

4. The method according to claim 3, in which the 3-hydroxypyridone is substituted only on the nitrogen atom or is substituted on the nitrogen atom and on one of the ring carbon atoms.

5. The method according to claim 4, in which the ring carbon atom substituent is a C.sub.1-4 aliphatic hydrocarbon group.

6. The method according to claim 5, in which the nitrogen atom is substituted by a C.sub.2-5 alkylcarbonyl group or by a C.sub.1-6 aliphatic hydrocarbon group substituted by a single substituent selected from C.sub.2-5 alkylcarbonyl, C.sub.1-4 alkoxy, halogen, hydroxy, C.sub.1-4 alkyl ester groups and unsubstituted or C.sub.1-4 alkyl mono- or di-substituted amide groups.

7. The method according to claim 3, in which the 3-hydroxypyridone is 3-hydroxypyrid-2-one, 3-hydroxypyrid-4-one, 3-hydroxy-2-methylpyrid-4-one, 3-hydroxy-6-methylpyrid-4-one or -3-hydroxy-2,6-dimethylpyrid-4-one with the hydrogen atom attached to the nitrogen atom replaced by an aliphatic acyl group --COR.sub.1, an aliphatic hydrocarbon group --(CH.sub.2).sub.n -- carrying a terminal substituent group --COR.sub.1, --COXR.sub.1, --SO.sub.2 XR.sub.1, --XCOR.sub.1 or --XSO.sub.2 R.sub.1, or an aliphatic hydrocarbon group --(CH.sub.2).sub.m --carrying a terminal substituent group --OH, wherein R.sub.1 is a C.sub.1-4 acyclic alkyl group, X is an oxy or imino group, n is an integer from 1 to 4 and m is an integer from 3 to 6.

8. A pharmaceutical composition comprising: (a) a 3-hydroxypyrid-2-one or 3-hydroxypyrid-4-one in which the hydrogen atom attached to the nitrogen atom is replaced by an aliphatic acyl group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by one or more substituents selected from aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen and hydroxy groups, and wherein one or more of the hydrogen atoms attached to ring carbon atoms can be replaced by an aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen or hydroxy group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by an alkoxy, aliphatic ester, halogen or hydroxy group, but excluding compounds in which said replacement of hydrogen atoms is effected only by aliphatic hydrocarbon groups, or a salt thereof containing a physiologically acceptable cation; and (b) a physiologically acceptable solid carrier.

9. A pharmaceutical composition comprising: (a) a 3-hydroxypyrid-2-one or 3-hydroxypyrid-4-one in which the hydrogen atom attached to the nitrogen atom is replaced by an aliphatic acyl group, an aliphatic hydrocarbon group or an aliphatic hydrocarbon group substituted by one or more substituents selected from aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen and hydroxy groups, and wherein one or more of the hydrogen atoms attached to ring carbon atoms can be replaced by an aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen or hydroxy group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by an alkoxy, aliphatic ester, halogen or hydroxy group, but excluding compounds in which said replacement of hydrogen atoms is effected only by aliphatic hydrocarbon groups, or a salt thereof containing a physiologically acceptable cation; and (b) a physiologically acceptable diluent which is sterile and pyrogen-free.

10. A pharmaceutical composition comprising: (a) a 3-hydroxypyrid-2-one or 3-hydroxypyrid-4-one in which the hydrogen atom attached to the nitrogen atom is replaced by in aliphatic acyl group, or an aliphatic hydrocarbon group substituted by one or more substituents selected from aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen and hydroxy groups, and wherein one or more of the hydrogen atoms attached to ring carbon atoms can be replaced by an aliphatic hydrocarbon group, but excluding the specific compounds 3-hydroxy-1-(2'-hydroxyethyl)-2-methylpyrid-4-one and 1-methoxycarbonylmethyl-3-hydroxy-2-methylpyrid-4-one, or a salt thereof containing a physiologically acceptable cation; and (b) a physiologically acceptable diluent or carrier.

11. The pharmaceutical composition according to claim 10, in which the nitrogen atom is substituted by a C.sub.2-5 alkylcarbonyl group or by a C.sub.1-6 aliphatic hydrocarbon group substituted by a single substituent selected from C.sub.2-5 alkylcarbonyl, C.sub.1-4 alkoxy, halogen, hydroxy, C.sub.1-4 alkyl ester groups and unsubstituted or C.sub.1-4 alkyl mono- or di-substituted amide groups, and wherein one of the ring carbon atoms can be substituted by a C.sub.1-4 aliphatic hydrocarbon group.

12. The pharmaceutical composition according to claims 10, in which the 3-hydroxypyridone is 3-hydroxypyrid-2-one, 3-hydroxypyrid-4-one, 3-hydroxy-2-methylpyrid-4-one, 3-hydroxy-6-methylpyrid-4-one or 3-hydroxy-2,6-dimethylpyrid-4-one with the hydrogen atom attached to the nitrogen atom replaced by an aliphatic acyl group --COR.sub.1, an aliphatic hydrocarbon group --(CH.sub.2).sub.n --carrying a terminal substituent group --COR.sub.1, --COXR.sub.1, --SO.sub.2 XR.sub.1, --XCOR.sub.1 or --XSO.sub.2 R.sub.1, or an aliphatic hydrocarbon group --(CH.sub.2).sub.m --carrying a terminal substituent group --OH, wherein R.sub.1 is a C.sub.1-4 acyclic alkyl group, X is an oxy or imino group, n is an integer from 1 to 4 and m is an integer from 3 to 6.

13. The pharmaceutical composition according to claim 10, in which the 3-hydroxypyridone is in the form of the free compound rather than in the form of a salt thereof.

14. The pharmaceutical composition according to claim 10, in which the carrier is a physiologically acceptable solid carrier.

15. The pharmaceutical composition according to claim 14, in tablet or capsule form.

16. The pharmaceutical composition according to claim 10 which comprises water and/or an organic solvent as the physiologically acceptable diluent and which has the form of a solution, suspension or emulsion.

17. The pharmaceutical composition according to claim 16 in sterile injectable form.

18. The pharmaceutical composition according to claim, 10 in unit dosage form.

20. The compound according to claim 19, in which the 3-hydroxypyridone is substituted only on the nitrogen atom or is substituted on the nitrogen atom and on one of the ring carbon atoms.

21. The compound according to claim 20 in which the ring carbon atom substituent is a C.sub.1-4 aliphatic hydrocarbon group.

22. The compound according to claim 19, being 3-hydroxypyrid-2-one, 3-hydroxypyrid-4-one, or a 2-alkyl-3-hydroxypyrid-4-one, 6-alkyl-3-hydroxypyrid-4-one, or 2,6-dialkyl-3-hydroxypyrid-4-one with the hydrogen atom attached to the nitrogen atom replaced by a C.sub.2-5 alkylcarbonyl group or by a C.sub.1-6 aliphatic hydrocarbon group substituted by a single substituent selected from C.sub.2-5 alkylcarbonyl, C.sub.1-4 alkoxy, halogen, hydroxy, C.sub.1-4 alkyl ester groups and unsubstituted or C.sub.1-4 alkyl mono- or di-substituted amide groups.

23. The compound according to claim 22, in which the alkyl groups at the 2-, 6- or 2- and 6-positions of the 3-hydroxypyridone are C.sub.1-3 acyclic groups.

24. The compound according to claim 19, being 3-hydroxypyrid-2-one. 3-hydroxypyrid-4-one, 2-methyl-3-hydroxypyrid-4-one, 6-methyl-3-hydroxypyrid-4-one or 2,6-dimethyl-3-hydroxypyrid-4-one with the hydrogen atom attached to the nitrogen atom replaced by an aliphatic acyl group --COR.sub.1, an aliphatic hydrocarbon group --(CH.sub.2).sub.n --carrying a terminal substituent group --COR.sub.1, --COXR.sub.1, --SO.sub.2 XR.sub.1, --XCOR.sub.1 or --XSO.sub.2 R.sub.1, or an aliphatic hydrocarbon group --(CH.sub.2).sub.m -- carrying a terminal substituent group --OH, wherein R.sub.1 is a C.sub.1-4 aliphatic hydrocarbon group, X is an oxy or imino group, n is an integer from 1 to 6, and m is an integer from 2 to 6.

25. The compound according to claim 24, in which the nitrogen atom is substituted by a group --(CH.sub.2).sub.n --COXR.sub.1 wherein --(CH.sub.2).sub.n --and R.sub.1 together contain 3 to 7 carbon atoms.

26. The compound according to claim 24, in which R.sub.1 is a C.sub.1-4 acyclic alkyl group, n is an integer from 1 to 4 and m is an integer from 3 to 6.

27. The compound according to claim 19 being 3-hydroxypyrid-2-one N-substituted by a group --(CH.sub.2).sub.n COXR.sub.1 or 3-hydroxy-2-methylpyrid-4-one N-substituted by a group --(CH.sub.2).sub.n COXR.sub.1 or --(CH.sub.2).sub.m XH wherein X is an oxy group, R.sub.1 is an acyclic alkyl group of 1 to 4 carbon atoms, n is an integer from 1 to 4 with the number of carbon atoms in --(CH.sub.2).sub.n --and R.sub.1 together being 3 to 7 carbon atoms, and m is an integer from 3 to 6.

28. The compound according to claim 19, in which the hydrogen atom attached to the nitrogen atom is replaced by an aliphatic hydrocarbon group and the hydrogen atom attached to the ring carbon atom at the 6-position is replaced by an alkoxymethyl, halomethyl or hydroxymethtyl group.

29. The compound according to claim 28, in which the aliphatic hydrocarbon group is an acyclic alkyl group of 1 to 4 carbon atoms.

31. A 3-hydroxypryd-2-one or 3-hydroxypyrid-4-one according to claim 30, in which the hydrogen atom attached to the nitrogen atom is replaced by a C.sub.1-8 aliphatic hydrocarbon group substituted by an aliphatic amide group and wherein one or more of the hydrogen atoms attached to ring carbon atoms can be replaced by a C.sub.1-6 aliphatic hydrocarbon group.

32. A method for the treatment of a patient having a toxic concentration of a metal selected from the group consisting of iron, copper, and aluminum in the body which comprises contacting the patient's blood outside the body with a 3-hydroxypyrid-2-one or 3-hydroxypyrid-4-one in which the hydrogen atom attached to the nitrogen atom is replaced by an aliphatic acyl group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by one or more substituents selected from aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen and hydroxy groups, and wherein one or more of the halogen atoms attached to ring carbon atoms can be replaced by an aliphatic acyl, alkoxy, aliphatic amide, aliphatic ester, halogen or hydroxy group, an aliphatic hydrocarbon group, or an aliphatic hydrocarbon group substituted by an alkoxy, aliphatic ester, halogen or hydroxy group, at least one hydrogen atom attached to either a nitrogen or a carbon atom being replaced by in aliphatic hydrocarbon group substituted by an aliphatic amide group, or by an aliphatic amide group, respectively, or a salt thereof containing a physiologically acceptable cation, the 3-hydroxypyridone or salt thereof being linked to a support material through said amide group.

33. The method according to claim 32, in which the metal is aluminum.

34. The method according to claim 32, which employs a 3-hydroxypyridone in which the hydrogen atom attached to the nitrogen atom is replaced by a C.sub.1-8 aliphatic hydrocarbon group substituted by an aliphatic amide group and wherein one or more of the hydrogen atoms attached to ring carbon atoms can be replaced by a C.sub.1-6 aliphatic hydrocarbon group..Iadd.

35. The method according to claim 1, in which the 3-hydroxypyridone is a 3-hydroxypyrid-4-one..Iaddend..Iadd.36. The method according to claim 35, in which the 3-hydroxypyrid-4-one is substituted at the 2-position..Iaddend..Iadd.37. The method according to claim 35, in which the 3-hydroxypyrid-4-one is an N-substituted 2-alkyl-3-hydroxypyrid-4-one, 6-alkyl-3-hydroxypyrid-4-one or 2,6-dialkyl-3-hydroxypyrid-4-one wherein the alkyl group is methyl, ethyl, propyl or isopropyl..Iaddend..Iadd.38. The method according to claim 1, in which the hydrogen atom attached to the nitrogen atom is replaced by a group --(CH.sub.2).sub.m OH wherein m is an integer of 2 to 4..Iaddend..Iadd.39. The method according to claim 35, in which the nitrogen atom of the 3-hydroxypyrid-4-one is substituted by a group --(CH.sub.2).sub.m OH wherein m is an integer of 2 to 4, and the ring carbon atoms are either unsubstituted or the ring carbon atom at the 2-position is substituted by a methyl or ethyl group..Iaddend..Iadd.40. The method according to claim 1, in which the hydrogen atom attached to the nitrogen atom is replaced by a C.sub.1 -C.sub.6 aliphatic hydrocarbon group substituted by a formyloxy, (C.sub.1 -C.sub.4 alkyl)-carbonyloxy, (C.sub.1 -C.sub.4 alkyl)-oxycarbonyl, (C.sub.1 -C.sub.4 alkyl)-sulphonyloxy or (C.sub.1 -C.sub.4 alkyl)-oxysulphonyl group..Iaddend..Iadd.41. The method according to claim 1, in which the 3-hydroxypyridone is 3-hydroxy-1-(2'-hydroxethyl)-2-methylpyrid-4-one or a salt thereof..Iaddend..Iadd.42. The method according to claim 1, in which the 3-hydroxypyridone is 3-hydroxy-1-(3'-hydroxypropyl)-2-methylpyrid-4-one or a salt thereof..Iaddend..Iadd.43. The pharmaceutical composition according to claim 10, in which the 3-hydroxypyridone is a 3-hydroxypyrid-4-one..Iaddend..Iadd.44. The pharmaceutical composition according to claim 43, in which the 3-hydroxypyrid-4-one is substituted at the 2-position..Iaddend..Iadd.45. The pharmaceutical composition according to claim 43, in which the 3-hydroxypyrid-4-one is an N-substituted 2-alkyl-3-hydroxypyrid-4-one, 6-alkyl-3-hydroxypyrid-4-one or 2,6-dialkyl-3-hydroxypyrid-4-one wherein the alkyl group is methyl, ethyl, propyl or isopropyl..Iaddend..Iadd.46. The pharmaceutical composition according to claim 10, in which the hydrogen atom attached to the nitrogen atom is replaced by a group --(CH.sub.2).sub.m OH wherein m is an integer of 2 to 4..Iaddend..Iadd.47. The pharmaceutical composition according to claim 43, in which the nitrogen atom of the 3-hydroxypyrid-4-one is substituted by a group --(CH.sub.2).sub.m OH wherein m is an integer of 2 to 4, and the ring carbon atoms are either unsubstituted or the ring carbon atom at the 2-position is substituted by a methyl or ethyl group..Iaddend..Iadd.48. The pharmaceutical composition according to claim 10, in which the hydrogen atom attached to the nitrogen atom is replaced by a C.sub.1 -C.sub.6 aliphatic hydrocarbon group substituted by a formyloxy, (C.sub.1 -C.sub.4 alkyl)-carbonyloxy, (C.sub.1 -C.sub.4 alkyl)-oxycarbonyl, (C.sub.1 -C.sub.4 alkyl)-sulphonyloxy or (C.sub.1 -C.sub.4 alkyl)-oxysulphonyl group..Iaddend..Iadd.49. The pharmaceutical composition according to claim 8, in which the 3-hydroxypyridone is 3-hydroxy-1-(2'-hydroxyethyl)-2-methylpyrid-4-one or a salt thereof.

.Iaddend..Iadd.50. The pharmaceutical composition according to claim 8, in which the 3-hydroxypyridone is 3-hydroxy-1-(3'-hydroxypropyl)-2-methylpyrid-4-one or a salt thereof..Iaddend..Iadd.51. The pharmaceutical composition according to claim 9, in which the 3-hydroxypyridone is 3-hydroxy-1-(2'-hydroxyethyl)-2-methylpyrid-4-one or a salt thereof..Iaddend..Iadd.52. The compound according to claim 19, which is a 3-hydroxypyrid-4-one..Iaddend..Iadd.53. The compound according to claim 52, which is substituted at the 2-position..Iaddend..Iadd.54. The compound according to claim 19, in which the 3-hydroxypyridone is 3-hydroxy-1-(3'-hydroxypropyl)-2-methylpyrid-4-one or a salt thereof..Iaddend..Iadd.55. The compound according to claim 52, which is an N-substituted 2-alkyl-3-hydroxypyrid-4-one, 6-alkyl-3-hydroxypyrid-4-one or 2,6-dialkyl-3-hydroxypyrid-4-one wherein the alkyl group is methyl, ethyl, propyl or isopropyl..Iaddend..Iadd.56. The compound according to claim 19, in which the hydrogen atom attached to the nitrogen atom is replaced by a group --(CH.sub.2).sub.m OH wherein m is an integer of 2 to 4..Iaddend..Iadd.57. The compound according to claim 52, in which the nitrogen atom of the 3-hydroxypyrid-4-one is substituted by a group --(CH.sub.2).sub.m OH wherein m is an integer of 2 to 4, and the ring carbon atoms are either unsubstituted or the ring carbon atom at the 2-position is substituted by a methyl or ethyl group..Iaddend..Iadd.58. The compound according to claim 19, in which the hydrogen atom attached to the nitrogen atom is replaced by a C.sub.1 -C.sub.6 aliphatic hydrocarbon group substituted by a formyloxy, (C.sub.1 -C.sub.4 alkyl)-carbonyloxy, (C.sub.1 -C.sub.4 alkyl)-oxycarbonyl, (C.sub.1 -C.sub.4 alkyl)-sulphonyloxy or (C.sub.1 -C.sub.4 alkyl)-oxysulphonyl group..Iaddend.

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Patent History
Patent number: RE35948
Type: Grant
Filed: Feb 17, 1995
Date of Patent: Nov 3, 1998
Assignee: British Technology Group Ltd. (London)
Inventors: Robert C. Hider (Clacton), George Kontoghiorghes (London), Jack Silver (London)
Primary Examiner: Alan L. Rotman
Law Firm: Nixon & Vanderhye
Application Number: 8/397,321