Highly water soluble dyes based on pyrazolone derivatives of carbohydrates

The synthesis of water soluble pyrazolone derivatives dyes was achieved. The pyrazolidin-3,5-dione 5a,b and pyrazolin-5-one 3a,b and 4a,b units were selected as the key building block to prepare the glycoconjugated H-chromophore 6a–d, 7a,b, azo 8a–d, 9a,b and bisazo 10a–d, 11a,b dyes pyrazolone derivatives based. The water solubility values show that these derivatives require a minimum percentage weight of 50% of the glycidic moiety to be water soluble and the 1H and 13C data confirmed the tendency of pyrazolone derivatives dyes to exist in their OH tautomer form.