New cephem compounds, process for preparation thereof and pharmaceutical compositions containing them

Claim 2

A new cephem compound of the formula: wherein R 1 is amino or protected amino, R 2 is lower aliphatic hydrocarbon group, R 3 is unsaturated condensed heterocyclic cation group containing more than one nitrogen atom, which may have suitable substituent(s) and X is CH or N, and pharmaceutically acceptable salts thereof.

Claim 3

A syn isomer of the compound of claim 1, wherein

Claim 4

A compound of claim 2, wherein R 1 is amino, R 2 is lower alkyl or lower alkenyl, and R 3 is a group of the formula: wherein m is 0 or 1, and n is 1 or 2, which may have lower alkyl.

Claim 5

A compound of claim 3, wherein R 2 is methyl, ethyl or allyl, and R 3 is 5,6-dihydro-lH,4H-cyclopenta[c]pyrazolio, 4,5,6,7-tetrahydro-lH-indazolio, 4,5,6,7-tetrahydro-2H-indazolio or 5,6,7,8-tetrahydrophthalazinio, each of which may have methyl.

Claim 6

A compound of claim 4, which is selected from the compound consisting of: 7-[2-allyloxyimino-2-(5-amino-l,2,4-thiadiazol-3-yl)-acetamido]-3-[1-methyl-5,6-dihydro-2(1H,4H)-cyclopenta[c]pyrazolio]methyl-3-cephem-4-carboxylate(syn isomer), 7-[2-ethoxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)-acetamido]-3-[1-methyl-5,6-dihydro-2(1H,4H)-cyclopenta[c]pyrazolio]methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-allyloxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-[1-methyl-5,6-dihydro-2(1H,4H)-cyclopenta[c]pyrazolio]-methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-methoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-[1-methyl-5,6-dihydro-2(1H,4H)-cyclopenta[c]pyrazolio]-methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-allyloxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)-acetamido]-3-[l-methyl-4,5,6,7-tetrahydro-2(lH)-indazolio]methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-allyloxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)-acetamido]-3-[2-methyl-4,5,6,7-tetrahydro-1(2H)-indazolio]methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-ethoxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)-acetamido]-3-[1-methyl-4,5,6,7-tetrahydro-2(lH)-indazolio]methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-methoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-[1-methyl-4,5,6,7-tetrahydro-2(1H)-indazolio]methyl-3-cephem-4-carboxylate (syn isomer), 7-[2-ethoxyimino-2-(5-amino-1,2,4-thiadiazol-3-yl)-acetamido]-3-(5,6,7,8-tetrahydro-2-phthalazinio)-methyl-3-cephem-4-carboxylate (syn isomer) and 7-[2-methoxyimino-2-(2-aminothiazol-4-yl)acetamido]-3-(5,6,7,8-tetrahydro-2-phthalazinio)methyl-3-cephem-4-carboxylate (syn isomer).

Claim 7

A process for preparing a compound of the formula: wherein R is amino or protected amino, R2 is lower aliphatic hydrocarbon group, R 3 is unsaturated condensed heterocyclic cation group containing more than one nitrogen atom, which may have suitable substituent(s) and X is CH or N, or a salt thereof, which comprises reacting a compound of the formula: wherein R 1 , R 2 and X are each as defined above, and R 4 is a group which can be substituted by a group R 3 , or a salt thereof, with R 5 wherein R 5 is unsaturated condensed heterocyclic compound containing more than one nitrogen atom, which may have suitable substituent(s), or a salt thereof.

Claim 8

A process for preparing a compound of the formula: wherein R is amino or protected amino, R2 is lower aliphatic hydrocarbon group, R 3 is unsaturated condensed heterocyclic cation group containing more than one nitrogen atom, which may have suitable substituent(s) and X is CH or N, or a salt thereof, which comprises reacting a compound of the formula: wherein R 1 , R 2 and X are each as defined above, and R 4 is a group which can be substituted by a group R 3 , or a salt thereof, with R 5 wherein R 5 is unsaturated condensed heterocyclic compound containing more than one nitrogen atom, which may have suitable substituent(s), or a salt thereof.

Claim 9

A pharmaceutical composition comprising an effective amount of compound of claim 1 or a pharmaceutically acceptable salt thereof as an effective ingredient, in association with a pharmaceutically acceptable, substantially non-toxic carrier or excipient.

Claim 10

A compound of claim 1 for use as a medicament.

Claim 11

A compound of claim 1 for use in treating infectious diseases.