HELP: pyrroletricarboxylic acid, thiazoledicarboxylic acid

[michael.micksche at univie.ac.atBettinaKammerer]

Hi,

For the determination of melanins by HPLC, I need
pyrrole-2,3,5-tricarboxylic acid (PTCA) and 
thiazole-4,5-dicarboxylic acid (TDCA).

Has anybody on the net informations where I can get these
substances commercially ?

Thanks in advance for your hints !

Bettina