A compound of formula wherein A is selected from the group A a consisting of, wherein above mentioned groups are substituted with one R 5 and one R 6; R 1 is selected from the group R 1a consisting of halogen, C 1- 3-alkyl- and C 3-6 -cycloalkyl-wherein the above mentioned C 1-3 -alkyl-, and C 3-6 -cycloalkyl- groups may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of halogen, NC- and HO-; R 2 is selected from the group R 2a consisting of aryl and heteroaryl, wherein the above mentioned aryl and heteroaryl-groups may optionally be substituted with 1 to 5 substituents R 4; R 3 is selected from the group R 3a consisting of H- and C 1-3 -alkyl-, wherein the above mentioned C 1-3 -alkyl-groups may optionally be substituted with 1 to 7 substituents independently from each other selected from the group consisting of halogen; R 4 is independently from each other selected from the group R 4a consisting of halogen, NC-, HO-, C 1-4 -alkyl- and C 1-3 -alkyl-O-wherein the above mentioned C 1-4 -alkyl- and C 1-3 -alkyl-O-groups may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of HO- and F-; R 5 is selected from the group R 5a consisting of H-, halogen, NC-, HO- and C 1-3 -alkyl-, wherein the above mentioned C 1-3 -alkyl-group may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of HO- and F- or R 5 and R 6 together form a group O=; R 6 is selected from the group R 6a consisting of H-, halogen, NC-, HO- and C 1-3 -alkyl-, wherein the above mentioned C 1-3 -alkyl-group may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of HO- and F- or R 5 and R 6 together form a group O=; or a salt thereof. A is selected from the group A a consisting of, wherein above mentioned groups are substituted with one R 5 and one R 6; R 1 is selected from the group R 1a consisting of halogen, C 1- 3-alkyl- and C 3-6 -cycloalkyl-wherein the above mentioned C 1-3 -alkyl-, and C 3-6 -cycloalkyl- groups may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of halogen, NC- and HO-; R 2 is selected from the group R 2a consisting of aryl and heteroaryl, wherein the above mentioned aryl and heteroaryl-groups may optionally be substituted with 1 to 5 substituents R 4; R 3 is selected from the group R 3a consisting of H- and C 1-3 -alkyl-, wherein the above mentioned C 1-3 -alkyl-groups may optionally be substituted with 1 to 7 substituents independently from each other selected from the group consisting of halogen; R 4 is independently from each other selected from the group R 4a consisting of halogen, NC-, HO-, C 1-4 -alkyl- and C 1-3 -alkyl-O-wherein the above mentioned C 1-4 -alkyl- and C 1-3 -alkyl-O-groups may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of HO- and F-; R 5 is selected from the group R 5a consisting of H-, halogen, NC-, HO- and C 1-3 -alkyl-, wherein the above mentioned C 1-3 -alkyl-group may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of HO- and F- or R 5 and R 6 together form a group O=; R 6 is selected from the group R 6a consisting of H-, halogen, NC-, HO- and C 1-3 -alkyl-, wherein the above mentioned C 1-3 -alkyl-group may optionally be substituted with 1 to 5 substituents independently selected from the group consisting of HO- and F- or R 5 and R 6 together form a group O=;