Patent ID: 7064231

Claim:
Compounds of the formula (I) where * marks stereogenic carbon atoms which each independently have R- or S-configuration, excluding meso-forms and R 1 , R 2 , R 3 and R 4 are each independently hydrogen, C 1 –C 12 -alkyl, C 4 –C 24 -aryl or C 5 –C 25 -arylalkyl, or R 1 , R 2 , R 3 and R 4 together with ethylene bridge are 1,2-(C 5 –C 8 -cycloalkyl) and R 5 and R 6 are each independently radicals which are selected from the group of —COOR 7 , —CONR 8 R 9 , —CN or —PO(OR 10 ) 2 where R 7 , R 8 , R 9 and R 10 are each C 1 –C 12 -alkyl, C 4 –C 24 -aryl or C 5 –C 25 -arylalkyl, or NR 8 R 9 as a whole is a cyclic amino radical having a total of 4 to 12 carbon atoms.