Organic compounds

A compound of Formula XI;

• in which
• R7 is hydrogen or alkyl C1 to 6;
• R8 is phenyl or a heteroaryl, each of which may be optionally substituted by one or more substituents selected from the group alkyl C1 to 6, haloalkyl C1 to 6, halogen, alkoxy C1 to 6, nitrile and dialkyl amino C1 to 6 or two adjacent substituents may together form a saturated or unsaturated carbocyclic or heterocyclic ring;
• R18, R19 and R20, which may be the same or different, are each hydrogen, alkyl C1 to 10, alkoxy C1 to 10, halogen, haloalkyl C1 to 10, halogenated alkoxy, morpholinyl, or imidazolinyl, or phenyl or phenoxy that is optionally substituted by one or more substituents selected from the group carboxy, alkyl C1 to 6, halogen and hydroxy;
• or R18 and R19 or R19 and R20 may together form a saturated or unsaturated carbocyclic or heterocyclic ring;
• in free form or in salt form.