Erythromycin derivatives

Claim 2

A compound of the general formula I or a pharmaceutically acceptable ester or acid addition salt thereof: wherein one of R l and R 2 denotes hydrogen and the other of R 1 and R2 denotes an amino group or a substituted amino group, or R 1 and R 2 together denote an oxime group, an oxime ether group, or an imino group; R3 denotes an unsubstituted or substituted alkyl group; R 4 denotes hydrogen or hydroxy; R 5 denotes hydrogen, an alkyl group, or a group of the formula -CHR 10 SR 11 ; R 7 denotes hydrogen or methyl; one of R8 and R 9 denotes hydrogen, hydroxy, alkoxy, alkanoyloxy, amino, substituted amino, or a group of the formula R 12 SO 2 -O-, and the other of R 8 and R 9 denotes hydrogen, or R 8 and R 9 together denote an oxo group, an oxime group, or a substituted oxime group; R 10 denotes hydrogen or an alkyl group; R ll denotes an alkyl group; and R 12 denotes an organic group.

Claim 3

A compound as claimed in claim 1, wherein R 3 denotes an unsubstituted or substituted primary (C l - 6 )alkyl group, especially a methyl group.

Claim 4

A compound as claimed in claim 1 or claim 2, wherein R i and R 2 together denote a group of the formula IV: in which R 13 denotes hydrogen or an unsubstituted or substituted hydrocarbon group especially a hydrogen atom or a methyl group.

Claim 5

A compound as claimed in any one of claims 1 to 3, wherein R 4 denotes a hydroxy group and R 7 denotes a methyl group.

Claim 6

A compound as claimed in any one of claims 1 to 4, wherein R 5 denotes a hydrogen atom.

Claim 7

A compound as claimed in any one of claims 1 to 5, wherein R 8 denotes a hydrogen atom and R 9 denotes a hydroxy group.

Claim 8

The compounds (i) 6-O-methylerythromycin A 9-methoxime; and (ii) 6-O-ethylerythromycin A 9-methoxime; corresponding 11-ether derivatives, and corresponding derivatives in which the 4' '-position is modified; and pharmaceutically acceptable esters and acid addition salts of such compounds.

Claim 9

The compounds (i) 6-O-methylerythromycin A 9-methoxime; and (ii) 6-O-ethylerythromycin A 9-methoxime; corresponding 11-ether derivatives, and corresponding derivatives in which the 4' '-position is modified; and pharmaceutically acceptable esters and acid addition salts of such compounds.

Claim 10

A process for the preparation of a compound of the general formula I defined in claim 1 or a pharmaceutically acceptable ester or acid addition salt thereof, which comprises reacting a compound of the general formula VI: wherein R 4, R 5, R 7, R 8 and R 9 are defined as in claim 1, R 18 denotes an oxime or oxime ether group, in which compound of the general formula VI any reactive group (other than the 6-hydroxy group) may optionally be protected, with an alkylating agent, to give a compound of the general formula I in which Rl and R 2 together denote an oxime ether group; and thereafter, if necessary or desired, carrying out one or more of the following steps in any suitable order: (a) converting a substitutent on the erythromycin structure to another such substituent in a conventional manner; (b) removing any protecting groups; and (c) forming a pharmaceutically acceptable ester or acid addition salt.

Claim 11

A process for the preparation of a compound of the general formula I defined in claim 1 in which R 3 denotes a methyl group, or a pharmaceutically acceptable ester or acid addition salt thereof, which comprises reacting a compound of the general formula VI: wherein R 4 , R 5 , R 7 , R 8 and R 9 are defined as in claim 1, R 18 denotes an oxime or oxime ether group, in which compound of the general formula VI the 2'-hydroxy group and/or the 3'-dimethylamino group is/are protected and any other reactive group (other than the 6-hydroxy group) may optionally be protected, with a methylating agent, to give a compound of the general formula I in which R l and R 2 together denote an oxime ether group, and R 3 denotes a methyl group; and thereafter, if necessary or desired, carrying out one or more of the following steps in any suitable order: (a) converting a substitutent on the erythromycin structure to another such substituent in a conventional manner; (b) removing any protecting groups; and (c) forming a pharmaceutically acceptable ester or acid addition salt.

Claim 12

A pharmaceutical composition which comprises a compound as claimed in any one of claims 1 to 7 in admixture or conjunction with a pharmaceutically acceptable carrier or excipient.

Claim 13

The use of a compound as claimed in any one of claims 1 to 7 for the manufacture of a medicament.