The invention relates to novel compounds with the ability to link an immune response to a pathogen, to the use of said compounds in a disease or disorder mediated and/or caused by an infective agent, to compositions containing said compounds, processes for their preparation and to novel intermediates used in said process.

The present invention relates to antimicrobial polymyxin derivative compounds and their uses, and in particular to peptide polymyxin antibiotics which may be used in the treatment of bacterial infections such as Gram negative bacterial infections, particularly those caused by multidrug-resistant (MDR) Gram negative bacterial infections.

The present invention relates to antimicrobial polymyxin derivative compounds and their uses, and in particular to peptide polymyxin antibiotics which may be used in the treatment of bacterial infections such as Gram negative bacterial infections, particularly those caused by multidrug-resistant (MDR) Gram negative bacterial infections.

Provided are compounds of formula (III), and the use of compounds of formula (III) in methods of treatment, such as methods of treating a microbial infection. The compounds of formula (III) is: where —R.sup.15 is an amino-containing group: and —R.sup.1, —R.sup.2, —R.sup.3, —R.sup.4, —R.sup.8, —R.sup.A, Q, —R.sup.16, —R.sup.17 are as described in further detail in the description.

##STR00001##

Provided are compounds of formula (III), and the use of compounds of formula (III) in methods of treatment, such as methods of treating a microbial infection. The compounds of formula (III) is: where —R.sup.15 is an amino-containing group: and —R.sup.1, —R.sup.2, —R.sup.3, —R.sup.4, —R.sup.8, —R.sup.A, Q, —R.sup.16, —R.sup.17 are as described in further detail in the description.

##STR00001##

Monoclonal antibodies against bacterial proteins that confer resistance to the antibiotic colistin and hybridomas that produce such monoclonal antibodies are described. The monoclonal antibodies have a strong affinity for MCR proteins and may be used in detection methods and kits to detect the presence of MCR proteins including variants thereof in a sample.

Provided are a ligand-bearing substrate which has a surface at least partially coated with a polymer (P3) containing structural units represented by the formulae (1a) and (1b) (in the formulae, R.sup.1, R.sup.2, X, Y, L, Q.sup.1, Q.sup.2, Q.sup.3, m1, m2 and n are as described in the claims and description); a raw material for such a substrate; and a method for producing such substrates.

Provided are a ligand-bearing substrate which has a surface at least partially coated with a polymer (P3) containing structural units represented by the formulae (1a) and (1b) (in the formulae, R.sup.1, R.sup.2, X, Y, L, Q.sup.1, Q.sup.2, Q.sup.3, m1, m2 and n are as described in the claims and description); a raw material for such a substrate; and a method for producing such substrates.

The invention provides a polymyxin compound of formula (I) and salts, solvates and protected forms thereof, pharmaceutical compositions comprising the compounds of formula (I), and the use of the compounds and compositions in methods of treatment, such as methods for the treatment of microbial infections. The compounds of formula (I) are represented thus:

##STR00001## wherein —R.sup.15 is a group:

##STR00002## and —R.sup.16 is hydrogen; —R.sup.17 is hydrogen; -L- is a covalent bond or methylene; and —Ar is optionally substituted aryl. The groups —X—, —R.sup.1, —R.sup.2, —R.sup.3, —R.sup.4, and —R.sup.8 are as defined herein.

The invention provides a polymyxin compound of formula (I) and salts, solvates and protected forms thereof, pharmaceutical compositions comprising the compounds of formula (I), and the use of the compounds and compositions in methods of treatment, such as methods for the treatment of microbial infections. The compounds of formula (I) are represented thus:

##STR00001## wherein —R.sup.15 is a group:

##STR00002## and —R.sup.16 is hydrogen; —R.sup.17 is hydrogen; -L- is a covalent bond or methylene; and —Ar is optionally substituted aryl. The groups —X—, —R.sup.1, —R.sup.2, —R.sup.3, —R.sup.4, and —R.sup.8 are as defined herein.