(mucic acid) [526-99-6] M 210.1, m 212-213 (dec) pK ²⁵ ₁ 3.09 (3.29), pK ²⁵ ₂ 3.63 (4.41). Dissolved in the minimum volume of dil aq NaOH, and ppted by adding dil HCl. The temperature should be kept below 25 .

D-Galactonic acid [576-36-3] M 196.2, m 148 , pK _Est 3.5. Crystd from EtOH. Cyclises to D-Galactonono-1,4-lactone, m 134-136 , [ ?] ³⁰ ₅₄₆ mutarotates in 1h to-92 (c 5,H ₂O).

D(-)-Galactono-1,4-lactone [2782-07-2] M 178.1, m 134-137 , [ ?] ²⁰ _D -78 (in H ₂O). Crystd from EtOH.

D(+)-Galactosamine hydrochloride [1772-03-8] M 215.6, m 181-185 , [ ?] ²⁵ _D + 96.4 (after 24h, c 3.2 in H ₂O), pK _Est 7.7 (free base). Dissolved in a small volume of H ₂O. Then added three volumes of EtOH, followed by acetone until faintly turbid and stood overnight in a refrigerator. [Roseman and Ludoweig J Am Chem Soc 76 301 1954].

?-D-Galactose [59-23-4] M 180.2, m 167-168 , [ ?] ²⁰ _D + 80.4 (after 24h, c 4 in H ₂O), pK ²⁵ 12.48. Crystd twice from aqueous 80% EtOH at -10 , then dried under vacuum over P ₂O ₅.

Gallic acid (H ₂O) (3.4.5-trihydroxybenzoic acid) [5995-86-8 H ₂O), 149-91-7] (anhydr)] M 188.1, m 253 (dec), pK ²⁵ ₁ 4.27, pK ²⁵ ₂ 8.68. Crystd from water.

Galvinoxyl...