Preparation of o-nitrophenyl-b-D-gal actopyranoside

after Beidman,M., and Link, K.B.

See Babers & Goebel, JBC 105:473, 1934.; Glaser & Wulwek, Bioch. Z. 145,514,'24.
42 g. o-nitrophenol in sol. 16.8 g NaOH/420 ml H20. Add sol. 88 g acetobrom-
galactose in 620 ml acetone. Keep at ret. Sh. Remove solvent under reduced
pressure-- filter off long needles, and concentrate further until crystals

no longer come out. Wash ppte water, air dry, recr. 95% EtOH. Weight: 56g.

mp 172.5.  (onpg-kexne AcO,, )

To deacetylate, a&#& lg. onpg-OAcy in 50 ml MeOH end 1 ml. -4N Ba(OMe), added.
Refrigerate, sheke periodically. After 4 h. , clear sol., then crystals as long
hairlike needles. After 24 h. conc. under red. pr. to 10 ml., and a quent.

yield of onpg is obtained. Recr. 2x EtOH. MP 196-7.

For Acetobrom galactose:

Suixnt) Gal-Oaes (acedg. to USBS ch4O) , 50 g. with 50 ml HBr/HacO (EK)
Stand 2h. Add 200 cc CHOL, pour mix into 1 1. icewaterz, separate, wash CHOLs
layer with NaHCOs, then water (cold). Dry over Nap@0,. Evap. Take up syrup
in Eto0 to crystallize. If necessar$, aas Petether to turb. to xuteskte

2

initiate cryst.