Patent ID: 8034797

Claim:
Compounds of formula (1): wherein R 1 and R 2 are identical or different and are in each case selected from the group consisting of: optionally substituted alkyl, optionally substituted alkenyl, optionally substituted aryl, optionally substituted alkylaryl; R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 and R 10 are identical or different and are in each case selected from the group consisting of: hydrogen, halogen, cyano, nitro, carboxyl, aminocarbonyl, sulfonic acid radical (—SO 3 H), aminosulfonyl, optionally substituted alkyl, optionally substituted alkoxy, optionally substituted alkenyl, optionally substituted aryl, optionally substituted alkylaryl; R 11 is optionally substituted alkanediyl or optionally substituted alkenediyl; R 12 is hydrogen and R 13 is optionally substituted alkyl or hydroxyl, or R 13 is hydrogen and R 12 is optionally substituted alkyl or hydroxyl, or R 12 and R 13 are each alkyl, wherein at least one of the alkyl groups has at least one substituent, or R 12 and R 13 , together with the nitrogen atom to which they are bonded, form a saturated or unsaturated, optionally substituted 5- to 8-membered ring which can optionally contain further heteroatoms; and X 1 is carbonyl, or pharmaceutically acceptable salts thereof.