abstract |
Compounds of Formula 1 are described herein:n n n Formula 1n n n n n n n n Here, each of R 1 , R 2 , R 3 , R 4 , R 5 and R 6 independently represents a linear or branched aliphatic group having 1 to 10 carbon atoms or an aromatic group having 5 to 20 carbon atoms. |