Cephem compounds
The present invention relates to a compound of the formula [I]: wherein R 1 is lower alkyl which may have suitable substituent(s), R 2 is amino, protected amino or guanidino, R 3 is carboxy or protected carboxy, R 4 is amino or protected amino, and A is lower alkylene, or a pharmaceutically acceptable salt thereof, a process for preparing a compound of the formula [I], and a pharmaceutical composition comprising a compound of the formula [I] in admixture with a pharmaceutically acceptable carrier.
1 . A compound of the formula [I]:
wherein
R 1 is lower alkyl which may have suitable substituent(s),
R 2 is amino, protected amino or guanidino,
R 3 is carboxy or protected carboxy,
R 4 is amino or protected amino, and
A is lower alkylene,
or a pharmaceutically acceptable salt thereof.
2 . A process for preparing a compound of the formula [I]:
wherein
R 1 is lower alkyl which may have suitable substituent(s),
R 2 is amino, protected amino or guanidino,
R 3 is carboxy or protected carboxy,
R 4 is amino or protected amino, and
A is lower alkylene,
or a salt thereof, which comprises
(1) reacting a compound of the formula [II]:
wherein R 1 , R 2 and A are each as defined above, or its reactive derivative at the amino group, or a salt thereof with a compound of the formula [III]:
wherein R 3 and R 4 are each as defined above, or its reactive derivative at the carboxy group, or a salt thereof to give a compound of the formula [I]:
wherein R 1 , R 2 , R 3 , R 4 and A are each as defined above, or a salt thereof, or
(2) reacting a compound of the formula [VI]:
wherein R 3 and R 4 are each as defined above, R 5 is protected carboxy, and Y is a leaving group, or a salt thereof with a compound of the formula [VII]:
wherein R 1 , R 2 and A are each as defined above, or a salt thereof to give a compound of the formula [VIII]:
wherein R 1 , R 2 , R 3 , R 4 , R 5 and A are each as defined above, and X {circle over (−)} is an anion, or a salt thereof, and subjecting the compound of the formula [VIII] or a salt thereof to elimination reaction of the carboxy protecting group, to give a compound of the formula [I]:
wherein R 1 , R 2 , R 3 , R 4 and A are each as defined above, or a salt thereof.
3 . A pharmaceutical composition comprising a compound of claim 1 or a pharmaceutically acceptable salt thereof in admixture with a pharmaceutically acceptable carrier.
4 . A compound of claim 1 or a pharmaceutically acceptable salt thereof for use as a medicament.
5 . A compound of claim 1 or a pharmaceutically acceptable salt thereof for use as an antimicrobial agent.
6 . Use of a compound of claim 1 or a pharmaceutically acceptable salt thereof for manufacture of a medicament for treating infectious diseases.
7 . A method for the treatment of infectious diseases which comprising administering a compound of claim 1 or a pharmaceutically acceptable salt thereof to human or animals.