H 1575 (OTTO) p-Hydroxy benzaldehyde, 99% Cas no 123-08-0 - used starting material for polymers and pharmaceuticals. p-Hydroxybenzaldehyde dehydrogenase is an enzyme found in carrots. H 1575 (OTTO) p-Hydroxy benzaldehyde, 99% Cas no 123-08-0 - used as a chemical that maintains bactericidal activity when tested against certain bacteria strains.