A compound of the following formula 1 wherein: R 1 is a C 10-20 hydrocarbon group; R 2 is a C 1-4 alkyl group, and R 3 is a C 1-4 alkyl group; or R 2 and R 3 are mutually linked to form a pyrrolidine ring, a piperidine ring or an azepane ring together with the nitrogen atom X to which they are attached, wherein said pyrrolidine ring, said piperidine ring or said azepane ring is optionally substituted with one or more groups independently selected from -OH, -O(C 1-3 alkyl), -O-C -(C 1-3 alkyl), C 1-3 alkyl, -C -(C 1-3 alkyl), -C -NH 2, -C -NH(C 1-3 alkyl), -C -N(C 1-3 alkyl)(C 1-3 alkyl), -NH 2, -NH(C 1-3 alkyl), -N(C 1-3 alkyl)(C 1-3 alkyl), -NH-C -(C 1-3 alkyl), -N(C 1-3 alkyl)-C -(C 1-3 alkyl), -NH-C -O(C 1-3 alkyl), or -N(C 1-3 alkyl)-C -O(C 1-3 alkyl); R 4 is a C 1-6 alkylene group; R 5 is -SO 3 -, -SO 3 H, -PO 3 H -, -PO 3 2-, -PO 3 H 2, -PO 2 (OC 1-3 alkyl)-, -PO 2 H(OC 1-3 alkyl), -PO(OC 1-3 alkyl) 2, -CO 2 -, -CO 2 H or -CO 2 (C 1-3 alkyl); and X is N +; or a pharmaceutically acceptable salt or solvate thereof for use in the treatment, prevention or amelioration of an inflammatory, autoimmune and/or allergic disorder selected from: psoriasis, atopic dermatitis (atopic eczema), contact dermatitis, xerotic eczema, seborrheic dermatitis, neurodermitis, dyshidrosis, discoid eczema, venous eczema, dermatitis herpetiformis (Duhring's Disease), autoeczematization, dermatomyositis, hyper-lgE (Buckley) syndrome, Wiskott-Aldrich syndrome, anaphylaxis, food allergy, allergic reactions to venomous stings, acute urticarias, chronic urticarias, physical urticarias including aquagenic urticaria, cholinergic urticaria, cold urticaria (chronic cold urticaria), delayed pressure urticaria, dermatographic urticaria, heat urticaria, solar urticaria, vibration urticaria, adrenergic urticaria, urticaria angioedema, inflammatory bowel disease, Crohn's disease, ulcerative colitis, collagenous colitis, lymphocytic colitis, diversion colitis (diverticulitis), Behçet's syndrome, indeterminate colitis, celiac disease, irritable bowel syndrome, post-operative ileus, eosinophilic gastroenteropathy, gastritis, chronic allergic rhinitis, seasonal allergic rhinitis (hay-fever), allergic conjunctivitis, chemical conjunctivitis, neonatal conjunctivitis, Sjogren syndrome, open-angle glaucoma, dry eye disease, diabetic macular edema, chronic obstructive pulmonary disease (COPD), allergic asthma, allergic bronchopulmonary aspergillosis, hypersensitivity pneumonitis, lung fibrosis, rheumatoid arthritis, juvenile rheumatoid arthritis, ankylosing spondylitis, systemic lupus erythematosus, scleroderma, reactive arthritis, polymyalgia rheumatica, Guillain-Barre syndrome, Hashimoto's thyroiditis, Grave's disease, temporal arteritis, primary biliary cirrhosis, sclerosing cholangitis, autoimmune hepatitis, or alopecia areata. R 1 is a C 10-20 hydrocarbon group; R 2 is a C 1-4 alkyl group, and R 3 is a C 1-4 alkyl group; or R 2 and R 3 are mutually linked to form a pyrrolidine ring, a piperidine ring or an azepane ring together with the nitrogen atom X to which they are attached, wherein said pyrrolidine ring, said piperidine ring or said azepane ring is optionally substituted with one or more groups independently selected from -OH, -O(C 1-3 alkyl), -O-C -(C 1-3 alkyl), C 1-3 alkyl, -C -(C 1-3 alkyl), -C -NH 2, -C -NH(C 1-3 alkyl), -C -N(C 1-3 alkyl)(C 1-3 alkyl), -NH 2, -NH(C 1-3 alkyl), -N(C 1-3 alkyl)(C 1-3 alkyl), -NH-C -(C 1-3 alkyl), -N(C 1-3 alkyl)-C -(C 1-3 alkyl), -NH-C -O(C 1-3 alkyl), or -N(C 1-3 alkyl)-C -O(C 1-3 alkyl); R 4 is a C 1-6 alkylene group; R 5 is -SO 3 -, -SO 3 H, -PO 3 H -, -PO 3 2-, -PO 3 H 2, -PO 2 (OC 1-3 alkyl)-, -PO 2 H(OC 1-3 alkyl), -PO(OC 1-3 alkyl) 2, -CO 2 -, -CO 2 H or -CO 2 (C 1-3 alkyl); and X is N +;